picture
RJR-logo

About | BLOGS | Portfolio | Misc | Recommended | What's New | What's Hot

About | BLOGS | Portfolio | Misc | Recommended | What's New | What's Hot

icon

Bibliography Options Menu

icon
QUERY RUN:
31 Jul 2021 at 01:37
HITS:
1161
PAGE OPTIONS:
Hide Abstracts   |   Hide Additional Links
NOTE:
Long bibliographies are displayed in blocks of 100 citations at a time. At the end of each block there is an option to load the next block.

Bibliography on: Corvids: Behavior

RJR-3x

Robert J. Robbins is a biologist, an educator, a science administrator, a publisher, an information technologist, and an IT leader and manager who specializes in advancing biomedical knowledge and supporting education through the application of information technology. More About:  RJR | OUR TEAM | OUR SERVICES | THIS WEBSITE

RJR: Recommended Bibliography 31 Jul 2021 at 01:37 Created: 

Corvids: Behavior

Audubon Magazine: Members of the crow family, known as the corvids, are among the smartest birds in the world. Some are capable of using tools, playing tricks, teaching each other new things, even holding "funerals." And yet there's still much we don't know about these fascinating, sometimes confounding creatures. All corvids have relatively big brains for their size. But while a seed storer like a Pinyon Jay or a nutcracker has a huge hippocampus — a region involved in memory — crows and ravens are more like primates. They have exceptionally large forebrains, the domain of analytical thought, higher-level sensory processing, and flexible behavior.

Created with PubMed® Query: (behavior OR behaviour OR ethology) AND \(corvus[TIAB] OR corvid[TIAB] OR OR corvids[TIAB] OR corvidae[TIAB] OR crow[TIAB] OR crows[TIAB] OR raven[TIAB] OR ravens[TIAB] OR jay[TIAB] OR jays[TIAB] OR magpie[TIAB] OR magpies[TIAB] OR jackdaw[TIAB] OR jackdaws[TIAB]) NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)

-->

RevDate: 2021-07-19
CmpDate: 2021-07-19

Smith OM, Snyder WE, JP Owen (2020)

Are we overestimating risk of enteric pathogen spillover from wild birds to humans?.

Biological reviews of the Cambridge Philosophical Society, 95(3):652-679.

Enteric illnesses remain the second largest source of communicable diseases worldwide, and wild birds are suspected sources for human infection. This has led to efforts to reduce pathogen spillover through deterrence of wildlife and removal of wildlife habitat, particularly within farming systems, which can compromise conservation efforts and the ecosystem services wild birds provide. Further, Salmonella spp. are a significant cause of avian mortality, leading to additional conservation concerns. Despite numerous studies of enteric bacteria in wild birds and policies to discourage birds from food systems, we lack a comprehensive understanding of wild bird involvement in transmission of enteric bacteria to humans. Here, we propose a framework for understanding spillover of enteric pathogens from wild birds to humans, which includes pathogen acquisition, reservoir competence and bacterial shedding, contact with people and food, and pathogen survival in the environment. We place the literature into this framework to identify important knowledge gaps. Second, we conduct a meta-analysis of prevalence data for three human enteric pathogens, Campylobacter spp., E. coli, and Salmonella spp., in 431 North American breeding bird species. Our literature review revealed that only 3% of studies addressed the complete system of pathogen transmission. In our meta-analysis, we found a Campylobacter spp. prevalence of 27% across wild birds, while prevalence estimates of pathogenic E. coli (20%) and Salmonella spp. (6.4%) were lower. There was significant bias in which bird species have been tested, with most studies focusing on a small number of taxa that are common near people (e.g. European starlings Sturnus vulgaris and rock pigeons Columba livia) or commonly in contact with human waste (e.g. gulls). No pathogen prevalence data were available for 65% of North American breeding bird species, including many commonly in contact with humans (e.g. black-billed magpie Pica hudsonia and great blue heron Ardea herodias), and our metadata suggest that some under-studied species, taxonomic groups, and guilds may represent equivalent or greater risk to human infection than heavily studied species. We conclude that current data do not provide sufficient information to determine the likelihood of enteric pathogen spillover from wild birds to humans and thus preclude management solutions. The primary focus in the literature on pathogen prevalence likely overestimates the probability of enteric pathogen spillover from wild birds to humans because a pathogen must survive long enough at an infectious dose and be a strain that is able to colonize humans to cause infection. We propose that future research should focus on the large number of under-studied species commonly in contact with people and food production and demonstrate shedding of bacterial strains pathogenic to humans into the environment where people may contact them. Finally, studies assessing the duration and intensity of bacterial shedding and survival of bacteria in the environment in bird faeces will help provide crucial missing information necessary to calculate spillover probability. Addressing these essential knowledge gaps will support policy to reduce enteric pathogen spillover to humans and enhance bird conservation efforts that are currently undermined by unsupported fears of pathogen spillover from wild birds.

RevDate: 2021-07-14

Breen AJ (2021)

Animal culture research should include avian nest construction.

Biology letters, 17(7):20210327.

Material culture-that is, group-shared and socially learned object-related behaviour(s)-is a widespread and diverse phenomenon in humans. For decades, researchers have sought to confirm the existence of material culture in non-human animals; however, the main study systems of interest-namely, tool making and/or using non-human primates and corvids-cannot provide such confirmatory evidence: because long-standing ethical and logistical constraints handicap the collection of necessary experimental data. Synthesizing evidence across decades and disciplines, here, I present a novel framework for (mechanistic, developmental, behavioural, and comparative) study on animal material culture: avian nest construction.

RevDate: 2021-07-13

Steele MP, Neaves LE, Klump BC, et al (2021)

DNA barcoding identifies cryptic animal tool materials.

Proceedings of the National Academy of Sciences of the United States of America, 118(29):.

Some animals fashion tools or constructions out of plant materials to aid foraging, reproduction, self-maintenance, or protection. Their choice of raw materials can affect the structure and properties of the resulting artifacts, with considerable fitness consequences. Documenting animals' material preferences is challenging, however, as manufacture behavior is often difficult to observe directly, and materials may be processed so heavily that they lack identifying features. Here, we use DNA barcoding to identify, from just a few recovered tool specimens, the plant species New Caledonian crows (Corvus moneduloides) use for crafting elaborate hooked stick tools in one of our long-term study populations. The method succeeded where extensive fieldwork using an array of conventional approaches-including targeted observations, camera traps, radio-tracking, bird-mounted video cameras, and behavioral experiments with wild and temporarily captive subjects-had failed. We believe that DNA barcoding will prove useful for investigating many other tool and construction behaviors, helping to unlock significant research potential across a wide range of study systems.

RevDate: 2021-07-02

Amor N, Noman MT, Petru M, et al (2021)

Neural network-crow search model for the prediction of functional properties of nano TiO2 coated cotton composites.

Scientific reports, 11(1):13649.

This paper presents a new hybrid approach for the prediction of functional properties i.e., self-cleaning efficiency, antimicrobial efficiency and ultraviolet protection factor (UPF), of titanium dioxide nanoparticles (TiO2 NPs) coated cotton fabric. The proposed approach is based on feedforward artificial neural network (ANN) model called a multilayer perceptron (MLP), trained by an optimized algorithm known as crow search algorithm (CSA). ANN is an effective and widely used approach for the prediction of extremely complex problems. Various studies have been proposed to improve the weight training of ANN using metaheuristic algorithms. CSA is a latest and an effective metaheuristic method relies on the intelligent behavior of crows. CSA has been never proposed to improve the weight training of ANN. Therefore, CSA is adopted to optimize the initial weights and thresholds of the ANN model, in order to improve the training accuracy and prediction performance of functional properties of TiO2 NPs coated cotton composites. Furthermore, our proposed algorithm i.e., multilayer perceptron with crow search algorithm (MLP-CSA) was applied to map out the complex input-output conditions to predict the optimal results. The amount of chemicals and reaction time were selected as input variables and the amount of titanium dioxide coated on cotton, self-cleaning efficiency, antimicrobial efficiency and UPF were evaluated as output results. A sensitivity analysis was carried out to assess the performance of CSA in prediction process. MLP-CSA provided excellent result that were statistically significant and highly accurate as compared to standard MLP model and other metaheuristic algorithms used in the training of ANN reported in the literature.

RevDate: 2021-06-29

Laumer IB, Massen JJM, Boehm PM, et al (2021)

Individual Goffin´s cockatoos (Cacatua goffiniana) show flexible targeted helping in a tool transfer task.

PloS one, 16(6):e0253416 pii:PONE-D-20-38887.

Flexible targeted helping is considered an advanced form of prosocial behavior in hominoids, as it requires the actor to assess different situations that a conspecific may be in, and to subsequently flexibly satisfy different needs of that partner depending on the nature of those situations. So far, apart from humans such behaviour has only been experimentally shown in chimpanzees and in Eurasian jays. Recent studies highlight the prosocial tendencies of several bird species, yet flexible targeted helping remained untested, largely due to methodological issues as such tasks are generally designed around tool-use, and very few bird species are capable of tool-use. Here, we tested Goffin's cockatoos, which proved to be skilled tool innovators in captivity, in a tool transfer task in which an actor had access to four different objects/tools and a partner to one of two different apparatuses that each required one of these tools to retrieve a reward. As expected from this species, we recorded playful object transfers across all conditions. Yet, importantly and similar to apes, three out of eight birds transferred the correct tool more often in the test condition than in a condition that also featured an apparatus but no partner. Furthermore, one of these birds transferred that correct tool first more often before transferring any other object in the test condition than in the no-partner condition, while the other two cockatoos were marginally non-significantly more likely to do so. Additionally, there was no difference in the likelihood of the correct tool being transferred first for either of the two apparatuses, suggesting that these birds flexibly adjusted what to transfer based on their partner´s need. Future studies should focus on explanations for the intra-specific variation of this behaviour, and should test other parrots and other large-brained birds to see how this can be generalized across the class and to investigate the evolutionary history of this trait.

RevDate: 2021-06-26

Wheeler SS, Taff CC, Reisen WK, et al (2021)

Mosquito blood-feeding patterns and nesting behavior of American crows, an amplifying host of West Nile virus.

Parasites & vectors, 14(1):331.

BACKGROUND: Although American crows are a key indicator species for West Nile virus (WNV) and mount among the highest viremias reported for any host, the importance of crows in the WNV transmission cycle has been called into question because of their consistent underrepresentation in studies of Culex blood meal sources. Here, we test the hypothesis that this apparent underrepresentation could be due, in part, to underrepresentation of crow nesting habitat from mosquito sampling designs. Specifically, we examine how the likelihood of a crow blood meal changes with distance to and timing of active crow nests in a Davis, California, population.

METHODS: Sixty artificial mosquito resting sites were deployed from May to September 2014 in varying proximity to known crow nesting sites, and Culex blood meal hosts were identified by DNA barcoding. Genotypes from crow blood meals and local crows (72 nestlings from 30 broods and 389 local breeders and helpers) were used to match mosquito blood meals to specific local crows.

RESULTS: Among the 297 identified Culex blood meals, 20 (6.7%) were attributable to crows. The mean percentage of blood meals of crow origin was 19% in the nesting period (1 May-18 June 2014), but 0% in the weeks after fledging (19 June-1 September 2014), and the likelihood of a crow blood meal increased with proximity to an active nest: the odds that crows hosted a Culex blood meal were 38.07 times greater within 10 m of an active nest than > 10 m from an active nest. Nine of ten crow blood meals that could be matched to a genotype of a specific crow belonged to either nestlings in these nests or their mothers. Six of the seven genotypes that could not be attributed to sampled birds belonged to females, a sex bias likely due to mosquitoes targeting incubating or brooding females.

CONCLUSION: Data herein indicate that breeding crows serve as hosts for Culex in the initial stages of the WNV spring enzootic cycle. Given their high viremia, infected crows could thereby contribute to the re-initiation and early amplification of the virus, increasing its availability as mosquitoes shift to other moderately competent later-breeding avian hosts.

RevDate: 2021-06-30

Stocker M, Prosl J, Vanhooland LC, et al (2021)

Measuring salivary mesotocin in birds - Seasonal differences in ravens' peripheral mesotocin levels.

Hormones and behavior, 134:105015 pii:S0018-506X(21)00094-5 [Epub ahead of print].

Oxytocin is involved in a broad array of social behaviours. While saliva has been used regularly to investigate the role of oxytocin in social behaviour of mammal species, so far, to our knowledge, no-one has tried to measure its homolog, mesotocin, in birds' saliva. Therefore, in this study we measured salivary mesotocin in common ravens (Corvus corax), and subsequently explored its link to three aspects of raven sociality. We trained ravens (n = 13) to voluntarily provide saliva samples and analysed salivary mesotocin with a commercial oxytocin enzyme-immunoassay kit, also suitable for mesotocin. After testing parallelism and recovery, we investigated the effect of bonding status, sex and season on mesotocin levels. We found that mesotocin was significantly more likely to be detected in samples taken during the breeding season (spring) than during the mating season (winter). In those samples in which mesotocin was detected, concentrations were also significantly higher during the breeding than during the mating season. In contrast, bonding status and sex were not found to relate to mesotocin detectability and concentrations. The seasonal differences in mesotocin correspond to behavioral patterns known to be associated with mesotocin/oxytocin, with ravens showing much more aggression during the mating season while being more tolerant of conspecifics in the breeding season. We show for the first time that saliva samples can be useful for the non-invasive determination of hormone levels in birds. However, the rate of successfully analysed samples was very low, and collection and analysis methods will benefit from further improvements.

RevDate: 2021-06-04

Freeman NE, Norris DR, Sutton AO, et al (2021)

Early-Life Corticosterone Body Condition Influence Social Status and Survival in a Food-Caching Passerine.

Integrative and comparative biology pii:6255751 [Epub ahead of print].

Individuals undergo profound changes throughout their early life as they grow and transition between life-history stages. As a result, the conditions that individuals experience during development can have both immediate and lasting effects on their physiology, behavior, and, ultimately, fitness. In a population of Canada jays in Algonquin Provincial Park, Ontario, Canada, we characterized the diet composition and physiological profile of young jays at three key time points during development (nestling, pre-fledge, and pre-dispersal) by quantifying stable-carbon (δ13C) and -nitrogen (δ15N) isotopes and corticosterone concentrations in feathers. We then investigated the downstream effects of early-life diet composition, feather corticosterone, and environmental conditions on a juvenile's social status, body condition, and probability of being observed in the fall following hatch. Across the three time points, the diet of Canada jay young was composed primarily of vertebrate tissue and human food with the proportion of these food items increasing as the jays neared dispersal. Feather corticosterone concentrations also shifted across the three time points, decreasing from nestling to pre-dispersal. Dominant juveniles had elevated corticosterone concentrations in their feathers grown pre-dispersal compared with subordinates. High body condition as nestlings was associated with high body condition as juveniles and an increased probability of being observed in the fall. Together, our results demonstrate that nestling physiology and body condition influence the social status and body condition once individuals are independent, with potential long-term consequences on survival and fitness.

RevDate: 2021-06-07

Chakarov N, Veiga J, Ruiz-Arrondo I, et al (2021)

Atypical behavior of a black fly species connects cavity-nesting birds with generalist blood parasites in an arid area of Spain.

Parasites & vectors, 14(1):298.

BACKGROUND: The feeding behavior of bloodsucking insects determines the transmission, distribution, host spectrum and evolution of blood parasites in the wild. Conventional wisdom suggests that some vector groups (e.g. black flies, family Simuliidae) are consistently exophagous daytime biters. We aimed to understand more about the exceptions to this pattern by combining targeted trapping and molecular identification of parasites in vectors.

METHODS: In this study, we collected black flies in nest boxes used by European rollers Coracias garrulus in southeastern Spain. We molecularly analyzed 434 individual insects, identifying the black fly species caught in the nest boxes, their potential vertebrate blood meals, and the haemosporidian parasite lineages that they carried.

RESULTS: Only one black fly species, Simulium rubzovianum, appeared to enter the nest boxes of rollers. Among the trapped specimens, 15% contained vertebrate DNA, which always belonged to rollers, even though only half of those specimens were visibly engorged. Furthermore, 15% of all black flies contained Leucocytozoon lineages, indicating previous feeding on avian hosts but probably not on infected adult rollers. The known vertebrate hosts of the recorded Leucocytozoon lineages suggested that large and/or abundant birds are their hosts. Particularly represented were cavity-nesting species breeding in the vicinity, such as pigeons, corvids and owls. Open-nesting species such as thrushes and birds of prey were also represented.

CONCLUSIONS: Our data strongly suggest that S. rubzovianum bites uninfected roller nestlings and infected individuals of other species, potentially incubating adults, inside nest boxes and natural cavities. This simuliid does not appear to have a strong preference for specific host clades. Contrary to the general pattern for the group, and possibly enhanced by the harsh environmental conditions in the study area, this black fly appeared to intensively use and may even have a preference for confined spaces such as cavities for feeding and resting. Preferences of vectors for atypical microhabitat niches where hosts are less mobile may enable social and within-family transmission and parasite speciation in the long term. At the same time, a lack of host preference in concentrated multispecies communities can lead to host switches. Both processes may be underappreciated driving forces in the evolution of avian blood parasites.

RevDate: 2021-06-26

Horn L, Zewald JS, Bugnyar T, et al (2021)

Carrion Crows and Azure-Winged Magpies Show No Prosocial Tendencies When Tested in a Token Transfer Paradigm.

Animals : an open access journal from MDPI, 11(6):.

To study the evolution of humans' cooperative nature, researchers have recently sought comparisons with other species. Studies investigating corvids, for example, showed that carrion crows and azure-winged magpies delivered food to group members when tested in naturalistic or simple experimental paradigms. Here, we investigated whether we could replicate these positive findings when testing the same two species in a token transfer paradigm. After training the birds to exchange tokens with an experimenter for food rewards, we tested whether they would also transfer tokens to other birds, when they did not have the opportunity to exchange the tokens themselves. To control for the effects of motivation, and of social or stimulus enhancement, we tested each individual in three additional control conditions. We witnessed very few attempts and/or successful token transfers, and those few instances did not occur more frequently in the test condition than in the controls, which would suggest that the birds lack prosocial tendencies. Alternatively, we propose that this absence of prosociality may stem from the artificial nature and cognitive complexity of the token transfer task. Consequently, our findings highlight the strong impact of methodology on animals' capability to exhibit prosocial tendencies and stress the importance of comparing multiple experimental paradigms.

RevDate: 2021-06-08

Cunha FCR, M Griesser (2021)

Who do you trust? Wild birds use social knowledge to avoid being deceived.

Science advances, 7(22):.

Many species give deceptive warning calls, enabled by the high risk of ignoring them. In Siberian jays, a territorial, group-living bird, individuals give warning calls toward perched predators and mob them. However, intruding neighbors can emit these warning calls in the absence of predators to access food, but breeders often ignore these calls. Playback field experiments show that breeders flee sooner and return later after warning calls of former group members than those of neighbors or unknown individuals. Thus, breeders respond appropriately only to warning calls of previous cooperation partners. This mechanism facilitates the evolution and maintenance of communication vulnerable to deceptive signaling. This conclusion also applies to human language because of its cooperative nature and thus, its vulnerability to deception.

RevDate: 2021-06-07

Fielding MW, Buettel JC, Brook BW, et al (2021)

Roadkill islands: Carnivore extinction shifts seasonal use of roadside carrion by generalist avian scavenger.

The Journal of animal ecology [Epub ahead of print].

Global road networks facilitate habitat modification and are integral to human expansion. Many animals, particularly scavengers, use roads as they provide a reliable source of food, such as carrion left after vehicle collisions. Tasmania is often cited as the 'roadkill capital of Australia', with the isolated offshore islands in the Bass Strait experiencing similar, if not higher, levels of roadkill. However, native mammalian predators on the islands are extirpated, meaning the remaining scavengers are likely to experience lower interference competition. In this study, we used a naturally occurring experiment to examine how the loss of mammalian carnivores within a community impacts roadside foraging behaviour by avian scavengers. We monitored the locations of roadkill and forest ravens Corvus tasmanicus, an abundant scavenger species, on eight road transects across the Tasmanian mainland (high scavenging competition) and the Bass Strait islands (low scavenging competition). We represented raven observations as one-dimensional point patterns, using hierarchical Bayesian models to investigate the dependence of raven spatial intensity on habitat, season, distance to roadkill and route location. We found that roadkill carcasses were a strong predictor of raven presence along road networks. The effect of roadkill was amplified on roads on the Bass Strait islands, where roadside carrion was a predictor of raven presence across the entire year. In contrast, ravens were more often associated with roadkill on Tasmanian mainland roads in the autumn, when other resources were low. This suggests that in the absence of competing mammalian scavengers, ravens choose to feed on roadside carrion throughout the year, even in seasons when other resources are available. This lack of competition could be disproportionately benefiting forest ravens, leading to augmented raven populations and changes to the vertebrate community structure. Our study provides evidence that scavengers modify their behaviour in response to reduced scavenger species diversity, potentially triggering trophic shifts and highlighting the importance of conserving or reintroducing carnivores within ecosystems.

RevDate: 2021-06-21

Hancock ZB, Lehmberg ES, GS Bradburd (2021)

Neo-darwinism still haunts evolutionary theory: A modern perspective on Charlesworth, Lande, and Slatkin (1982).

Evolution; international journal of organic evolution, 75(6):1244-1255.

The Modern Synthesis (or "Neo-Darwinism"), which arose out of the reconciliation of Darwin's theory of natural selection and Mendel's research on genetics, remains the foundation of evolutionary theory. However, since its inception, it has been a lightning rod for criticism, which has ranged from minor quibbles to complete dismissal. Among the most famous of the critics was Stephen Jay Gould, who, in 1980, proclaimed that the Modern Synthesis was "effectively dead." Gould and others claimed that the action of natural selection on random mutations was insufficient on its own to explain patterns of macroevolutionary diversity and divergence, and that new processes were required to explain findings from the fossil record. In 1982, Charlesworth, Lande, and Slatkin published a response to this critique in Evolution, in which they argued that Neo-Darwinism was indeed sufficient to explain macroevolutionary patterns. In this Perspective for the 75th Anniversary of the Society for the Study of Evolution, we review Charlesworth et al. in its historical context and provide modern support for their arguments. We emphasize the importance of microevolutionary processes in the study of macroevolutionary patterns. Ultimately, we conclude that punctuated equilibrium did not represent a major revolution in evolutionary biology - although debate on this point stimulated significant research and furthered the field - and that Neo-Darwinism is alive and well.

RevDate: 2021-06-24

Sharma S, Singh G, M Sharma (2021)

A comprehensive review and analysis of supervised-learning and soft computing techniques for stress diagnosis in humans.

Computers in biology and medicine, 134:104450 pii:S0010-4825(21)00244-4 [Epub ahead of print].

Stress is the most prevailing and global psychological condition that inevitably disrupts the mood and behavior of individuals. Chronic stress may gravely affect the physical, mental, and social behavior of victims and consequently induce myriad critical human disorders. Herein, a review has been presented where supervised learning (SL) and soft computing (SC) techniques used in stress diagnosis have been meticulously investigated to highlight the contributions, strengths, and challenges faced in the implementation of these methods in stress diagnostic models. A three-tier review strategy comprising of manuscript selection, data synthesis, and data analysis was adopted. The issues in SL strategies and the potential possibility of using hybrid techniques in stress diagnosis have been intensively investigated. The strengths and weaknesses of different SL (Bayesian classifier, random forest, support vector machine, and nearest neighbours) and SC (fuzzy logic, nature-inspired, and deep learning) techniques have been presented to obtain clear insights into these optimization strategies. The effects of social, behavioral, and biological stresses have been highlighted. The psychological, biological, and behavioral responses to stress have also been briefly elucidated. The findings of the study confirmed that different types of data/signals (related to skin temperature, electro-dermal activity, blood circulation, heart rate, facial expressions, etc.) have been used in stress diagnosis. Moreover, there is a potential scope for using distinct nature-inspired computing techniques (Genetic Algorithm, Particle Swarm Optimization, Ant Colony Optimization, Whale Optimization Algorithm, Butterfly Optimization, Harris Hawks Optimizer, and Crow Search Algorithm) and deep learning techniques (Deep-Belief Network, Convolutional-Neural Network, and Recurrent-Neural Network) on multimodal data compiled using behavioral testing, electroencephalogram signals, finger temperature, respiration rate, pupil diameter, galvanic-skin-response, and blood pressure. Likewise, there is a wider scope to investigate the use of SL and SC techniques in stress diagnosis using distinct dimensions such as sentiment analysis, speech recognition, handwriting recognition, and facial expressions. Finally, a hybrid model based on distinct computational methods influenced by both SL and SC techniques, adaption, parameter tuning, and the use of chaos, levy, and Gaussian distribution may address exploration and exploitation issues. However, factors such as real-time data collection, bias, integrity, multi-dimensional data, and data privacy make it challenging to design precise and innovative stress diagnostic systems based on artificial intelligence.

RevDate: 2021-05-04

Parishar P, Mohapatra AN, S Iyengar (2021)

Investigating Behavioral Responses to Mirrors and the Mark Test in Adult Male Zebra Finches and House Crows.

Frontiers in psychology, 12:637850.

Earlier evidence suggests that besides humans, some species of mammals and birds demonstrate visual self-recognition, assessed by the controversial "mark" test. Whereas, there are high levels of inter-individual differences amongst a single species, some species such as macaques and pigeons which do not spontaneously demonstrate mirror self-recognition (MSR) can be trained to do so. We were surprised to discover that despite being widely used as a model system for avian research, the performance of zebra finches (Taenopygia guttata) on the mark test had not been studied earlier. Additionally, we studied the behavioral responses of another species of passerine songbirds (Indian house crows; Corvus splendens) to a mirror and the MSR mark test. Although a small number of adult male zebra finches appeared to display heightened responses toward the mark while observing their reflections, we could not rule out the possibility that these were a part of general grooming rather than specific to the mark. Furthermore, none of the house crows demonstrated mark-directed behavior or increased self-exploratory behaviors when facing mirrors. Our study suggests that self-directed behaviors need to be tested more rigorously in adult male zebra finches while facing their reflections and these findings need to be replicated in a larger population, given the high degree of variability in mirror-directed behaviors.

RevDate: 2021-05-24
CmpDate: 2021-05-24

Shrader-Frechette K, AM Biondo (2021)

Health Misinformation about Toxic-Site Harm: The Case for Independent-Party Testing to Confirm Safety.

International journal of environmental research and public health, 18(8):.

Health misinformation can cause harm if regulators or private remediators falsely claim that a hazardous facility is safe. This misinformation especially threatens the health of children, minorities, and poor people, disproportionate numbers of whom live near toxic facilities. Yet, perhaps because of financial incentives, private remediators may use safety misinformation to justify reduced cleanup. Such incentives exist in nations like the United States, where most toxic-site testing/remediation is semi-privatized or voluntary, conducted by private parties, commercial redevelopers, who can increase profits by underestimating health harm, thus decreasing required testing/remediation. Our objective is to begin to determine whether or not interested parties misrepresent health harm (at hazardous facilities that they test/remediate/redevelop) when they use traditional and social media to claim that these sites are safe. Our hypothesis is that, contrary to the safety claims of the world's largest commercial developer, Coldwell Banker Real Estate/Trammell Crow (CBRE/TCC), the authors' screening assessment, especially its lab-certified, toxic-site, indoor-air tests, show violations of all three prominent government, cancer-safety benchmarks. If so, these facilities require additional testing/remediation, likely put site renters at risk, and may reveal problems with privatized hazardous cleanup. To our knowledge, we provide the first independent tests of privatized, toxic-site assessments before cancer reports occur. Our screening assessment of this hypothesis tests indoor air in rental units on a prominent former weapons-testing site (the US Naval Ordnance Testing Station, Pasadena, California (NOTSPA) that is subject to carcinogenic vapor intrusion by volatile organic compounds, VOCs), then compares test results to the redeveloper's site-safety claims, made to government officials and citizens through traditional and social media. Although NOTSPA toxic soil-gas concentrations are up to nearly a million times above allowed levels, and indoor air was never tested until now, both the regulator and the remediator (CBRE/TCC) have repeatedly claimed on social media that "the site is safe at this time." We used mainly Method TO-17 and two-week sampling with passive, sorbent tubes to assess indoor-air VOCs. Our results show that VOC levels at every location sampled-all in occupied site-rental units-violate all three government-mandated safety benchmarks: environmental screening levels (ESLs), No Significant Risk Levels (NSRLs), and inhalation risks based on the Inhalation Unit Risk (IUR); some violations are two orders of magnitude above multiple safety benchmarks. These results support our hypothesis and suggest a need for independent assessment of privatized cleanups and media-enhanced safety claims about them. If our results can be replicated at other sites, then preventing health misinformation and toxic-facility safety threats may require new strategies, one of which we outline.

RevDate: 2021-05-11

Pendergraft LT, Lehnert AL, JM Marzluff (2020)

Individual and social factors affecting the ability of American crows to solve and master a string pulling task.

Ethology : formerly Zeitschrift fur Tierpsychologie, 126(2):229-245.

Crows and other birds in the family Corvidae regularly share information to learn the identity and whereabouts of dangerous predators, but can they use social learning to solve a novel task for a food reward? Here we examined the factors affecting the ability of 27 wild-caught American crows to solve a common string-pulling task in a laboratory setting. We split crows into two groups; one group was given the task after repeatedly observing a conspecific model the solution, the other solved in the absence of conspecific models. We recorded the crows' estimated age, sex, size, body condition, level of nervousness, and brain volume using DICOM images from a CT scan. Although none of these variables were statistically significant, crows without a conspecific model and large brain volumes consistently mastered the task in the minimum number of days, whereas those with conspecific models and smaller brain volumes required varying and sometimes a substantial number of days to master the task. We found indirect evidence that body condition might also be important for motivating crows to solve the task. Crows with conspecific models were no more likely to initially solve the task than those working the puzzle without social information, but those that mastered the task usually copied the method most frequently demonstrated by their knowledgeable neighbors. These findings suggest that brain volume and possibly body condition may be factors in learning new tasks, and that crows can use social learning to refine their ability to obtain a novel food source, although they must initially learn to access it themselves.

RevDate: 2021-03-20

Kolkert HL, Smith R, Rader R, et al (2021)

Prey removal in cotton crops next to woodland reveals periodic diurnal and nocturnal invertebrate predation gradients from the crop edge by birds and bats.

Scientific reports, 11(1):5256.

Factors influencing the efficacy of insectivorous vertebrates in providing natural pest control services inside crops at increasing distances from the crop edge are poorly understood. We investigated the identity of vertebrate predators (birds and bats) and removal of sentinel prey (mealworms and beetles) from experimental feeding trays in cotton crops using prey removal trials, camera traps and observations. More prey was removed during the day than at night, but prey removal was variable at the crop edge and dependent on the month (reflecting crop growth and cover) and time of day. Overall, the predation of mealworms and beetles was 1-times and 13-times greater during the day than night, respectively, with predation on mealworms 3-5 times greater during the day than night at the crop edge compared to 95 m inside the crop. Camera traps identified many insectivorous birds and bats over crops near the feeding trays, but there was no evidence of bats or small passerines removing experimental prey. A predation gradient from the crop edge was evident, but only in some months. This corresponded to the foraging preferences of open-space generalist predators (magpies) in low crop cover versus the shrubby habitat preferred by small passerines, likely facilitating foraging away from the crop edge later in the season. Our results are in line with Optimal Foraging Theory and suggest that predators trade-off foraging behaviour with predation risk at different distances from the crop edge and levels of crop cover. Understanding the optimal farm configuration to support insectivorous bird and bat populations can assist farmers to make informed decisions regarding in-crop natural pest control and maximise the predation services provided by farm biodiversity.

RevDate: 2021-06-08

Rinnert P, A Nieder (2021)

Neural Code of Motor Planning and Execution during Goal-Directed Movements in Crows.

The Journal of neuroscience : the official journal of the Society for Neuroscience, 41(18):4060-4072.

The planning and execution of head-beak movements are vital components of bird behavior. They require integration of sensory input and internal processes with goal-directed motor output. Despite its relevance, the neurophysiological mechanisms underlying action planning and execution outside of the song system are largely unknown. We recorded single-neuron activity from the associative endbrain area nidopallium caudolaterale (NCL) of two male carrion crows (Corvus corone) trained to plan and execute head-beak movements in a spatial delayed response task. The crows were instructed to plan an impending movement toward one of eight possible targets on the left or right side of a touchscreen. In a fraction of trials, the crows were prompted to plan a movement toward a self-chosen target. NCL neurons signaled the impending motion direction in instructed trials. Tuned neuronal activity during motor planning categorically represented the target side, but also specific target locations. As a marker of intentional movement preparation, neuronal activity reliably predicted both target side and specific target location when the crows were free to select a target. In addition, NCL neurons were tuned to specific target locations during movement execution. A subset of neurons was tuned during both planning and execution period; these neurons experienced a sharpening of spatial tuning with the transition from planning to execution. These results show that the avian NCL not only represents high-level sensory and cognitive task components, but also transforms behaviorally-relevant information into dynamic action plans and motor execution during the volitional perception-action cycle of birds.SIGNIFICANCE STATEMENT Corvid songbirds have become exciting new models for understanding complex cognitive behavior. As a key neural underpinning, the endbrain area nidopallium caudolaterale (NCL) represents sensory and memory-related task components. How such representations are converted into goal-directed motor output remained unknown. In crows, we report that NCL neurons are involved in the planning and execution of goal-directed movements. NCL neurons prospectively signaled motion directions in instructed trials, but also when the crows were free to choose a target. NCL neurons showed a target-specific sharpening of tuning with the transition from the planning to the execution period. Thus, the avian NCL not only represents high-level sensory and cognitive task components, but also transforms relevant information into action plans and motor execution.

RevDate: 2021-02-19

Lozano-Ruiz A, Fasfous AF, Ibanez-Casas I, et al (2021)

Cultural Bias in Intelligence Assessment Using a Culture-Free Test in Moroccan Children.

Archives of clinical neuropsychology : the official journal of the National Academy of Neuropsychologists pii:6144703 [Epub ahead of print].

OBJECTIVE: Previous research has shown that cognitive tests can lead to misclassification when applying non-representative norms to measure cognitive performance. The objective of this study was to investigate whether this misclassification also occurs with a non-verbal so-called "culture-free" intelligence test administered to different age groups.

METHOD: The intelligence of a sample of healthy Moroccan children (N = 147) ages 7, 9, and 11 was assessed using the Coloured Raven's Progressive Matrices (CPM). Raw scores were used to study age differences, as well as misclassifications when applying the norms of three countries culturally different from Morocco (United Kingdom, Spain, and Oman).

RESULTS: Intelligence performance was not within the normal range when non-representative norms were applied to the Moroccan raw scores. Misclassifications accounted for a large percentage of the participants that supposedly displayed intelligence deficits, especially when applying the British norms. Up to 15.68% of the healthy children fell within the "intellectually impaired" range, and up to 62.5% fell "below average," with these percentages especially higher at older ages.

CONCLUSIONS: Our findings confirm that "culture-free" tests should be adapted to each culture and applied together with their culture's specific norms to prevent misclassification and allow for a better, unbiased neuropsychological assessment.

RevDate: 2021-02-01

Roelofs A (2021)

How attention controls naming: Lessons from Wundt 2.0.

Journal of experimental psychology. General pii:2021-13056-001 [Epub ahead of print].

When models of the attentional control of vocal naming, applied to color-word Stroop and picture-word interference, were first computationally implemented and examined in 1990, an implementable model proposed by Wundt (1880, 1902) was not considered. Although these modern computer models, and more recent ones, clarify many aspects of the interference, most models fail to explain its time course, as outlined in Roelofs (2003). Wundt's (1902) model assigns a key role to top-down inhibition, which is absent in most of the modern models. Here, an implementation of his model is presented, called Wundt 2.0. The necessity of perceptual inhibition was demonstrated by computer simulations of the interference and its time course, and supported by existing evidence from oscillatory brain activity in the alpha frequency band. Moreover, a new empirical study showed that Raven scores measuring the general intelligence factor g, discovered by Wundt's student Spearman (1904), predict the magnitude of the Stroop effect in fast errors, in line with the model and evidence on alpha band activity. Also, the study provided evidence that response inhibition is absent during vocal naming in the Stroop task. To conclude, Wundt's model has stood the test of time and provides a number of enduring lessons for our understanding of attention and performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

RevDate: 2021-04-30
CmpDate: 2021-04-30

Boone JD, Witt C, EM Ammon (2021)

Behavior-specific occurrence patterns of Pinyon Jays (Gymnorhinus cyanocephalus) in three Great Basin study areas and significance for pinyon-juniper woodland management.

PloS one, 16(1):e0237621.

The Pinyon Jay is a highly social, year-round inhabitant of pinyon-juniper and other coniferous woodlands in the western United States. Range-wide, Pinyon Jays have declined ~ 3-4% per year for at least the last half-century. Occurrence patterns and habitat use of Pinyon Jays have not been well characterized across much of the species' range, and obtaining this information is necessary for better understanding the causes of ongoing declines and determining useful conservation strategies. Additionally, it is important to better understand if and how targeted removal of pinyon-juniper woodland, a common and widespread vegetation management practice, affects Pinyon Jays. The goal of this study was to identify the characteristics of areas used by Pinyon Jays for several critical life history components in the Great Basin, which is home to nearly half of the species' global population, and to thereby facilitate the inclusion of Pinyon Jay conservation measures in the design of vegetation management projects. To accomplish this, we studied Pinyon Jays in three widely separated study areas using radio telemetry and direct observation and measured key attributes of their locations and a separate set of randomly-selected control sites using the U. S. Forest Service's Forest Inventory Analysis protocol. Data visualizations, principle components analysis, and logistic regressions of the resulting data indicated that Pinyon Jays used a distinct subset of available pinyon-juniper woodland habitat, and further suggested that Pinyon Jays used different but overlapping habitats for seed caching, foraging, and nesting. Caching was concentrated in low-elevation, relatively flat areas with low tree cover; foraging occurred at slightly higher elevations with generally moderate but variable tree cover; and nesting was concentrated in slightly higher areas with high tree and vegetation cover. All three of these Pinyon Jay behavior types were highly concentrated within the lower-elevation band of pinyon-juniper woodland close to the woodland-shrubland ecotone. Woodland removal projects in the Great Basin are often concentrated in these same areas, so it is potentially important to incorporate conservation measures informed by Pinyon Jay occurrence patterns into existing woodland management paradigms, protocols, and practices.

RevDate: 2021-03-11
CmpDate: 2021-03-11

Rial-Berriel C, Acosta-Dacal A, Cabrera Pérez MÁ, et al (2021)

Intensive livestock farming as a major determinant of the exposure to anticoagulant rodenticides in raptors of the Canary Islands (Spain).

The Science of the total environment, 768:144386.

The Canary Islands (Spain) is a biodiversity hotspot, with more than 4500 registered endemic species. However, it is subject to high anthropogenic pressure that threatens its wildlife in various ways. In the context of forensic toxicological surveys, the presence of anticoagulant rodenticides (AR) has been investigated in the liver of 831 animal carcasses with georeferenced data from 2011 to May 2020. The high concentrations of toxic pesticides in carcasses and in baits found close to the corpses indicated that all the reptiles and most of the mammals tested positive for AR were intentionally poisoned, although mainly by other substances. The frequency of detection of AR in non-raptor birds (n = 343) was only 4.1%, being the Canary raven the most frequently affected species (7/97, 7.2%). On the contrary, in raptors (n = 308) the detection frequency was almost 60%, with an average of more than 2 ARs per animal. The highest concentrations were found in the common kestrel. We present for the first-time results of AR contamination in two species of raptors that are very rare in Europe, Eleonora's falcon (n = 4) and Barbary falcon (n = 13). The temporal trend of positive cases remains stable, but since the entry into force of the restriction to the concentration of the active ingredient in baits (<30 ppm), a decrease in the concentrations of these compounds in the raptors' liver has been detected. Conversely, we registered an increase in the number of ARs per animal. From the study of the geographic information system (GIS) it can be deduced that intensive livestock farms are an important determinant in the exposure of raptors to ARs. Those birds that have their territory near intensive production farms have higher levels of exposure than those of birds that live far from such facilities.

RevDate: 2021-06-29

Tornick J, B Gibson (2021)

Clark's nutcrackers (Nucifraga columbiana) use a visual barrier for cache protection.

Journal of comparative psychology (Washington, D.C. : 1983), 135(2):170-175.

Previous work with corvids such as scrub jays (Aphelocoma californica) and ravens (Corvus corax) suggests that many social corvids alter their caching behavior when observed by conspecifics to protect their caches. We examined whether the Clark's nutcracker (Nucifraga columbiana), an asocial corvid, can utilize a barrier to conceal its caching activities from a conspecific observer. Nutcrackers were allowed to cache nuts in a visible or concealed location in either the presence or absence of an observer. Nutcrackers were also given experience of having their caches pilfered. The nutcrackers cached significantly more nuts in the concealed compared to a visible location when observed. Importantly, nutcrackers also recovered a larger percentage of their nuts 24 hr later from a visible cache location but when the observer was no longer present. The results extend recent work suggesting that relatively nonsocial corvids, similar to their more social relatives, also engage in multiple forms of cache protection. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

RevDate: 2021-01-16

Zhang Y, Yu C, Chen L, et al (2021)

Performance of Azure-winged magpies in Aesop's fable paradigm.

Scientific reports, 11(1):804.

In this study, the improved Aesop's fable paradigm-a series of experiments originally used to test whether some animals understand the causality associated with water replacement-was used to explore the cognitive ability of Azure-winged magpies (Cyanopica cyanus). Experimental results on causal cue tasks showed that the Azure-winged magpies prefer water-filled tubes over sand-filled tubes, heavy objects over light objects, and solid objects over hollow objects. However, they failed to notice the diameter and water level of the tubes. They also failed to pass the counterintuitive U-shaped tube task in arbitrary cue tasks. Our results demonstrated that Azure-winged magpies have a certain cognitive ability but not an understanding of causality, a characteristic comparable to that of other corvids. Moreover, Azure-winged magpies exhibited the ability of training transfer and analogical problem solving from the perspective of cognitive psychology. We believe that object-bias has little effect on Azure-winged magpies in this study. We can conclude that the Azure-winged magpies partially completed the tasks by trial-and-error learning.

RevDate: 2021-06-30
CmpDate: 2021-06-30

Wenig K, Boucherie PH, T Bugnyar (2021)

Early evidence for emotional play contagion in juvenile ravens.

Animal cognition, 24(4):717-729.

Perceiving, evaluating and reacting towards conspecifics' emotional states are important challenges of social group living. Emotional contagion describes an alignment of emotional states between individuals and is widely believed to be based on behavioral synchronization, i.e., behavioral contagion. As basic empathy-like processes, the occurrence of both forms of contagion seems to underlie early ontogenetic trajectories in humans and non-human species. In the present study, we assessed play as a context for studying the development of emotional contagion and its interlink with behavioral contagion in ten juvenile common ravens. Ravens are exceptional players that engage in all three forms of play: object, locomotion and social play. To assess potential ontogenetic patterns of both behavioral and emotional contagion, we tested juvenile ravens at two different periods of early development, at three- and six-month post-hatching. We elicited object play in one or several ravens (demonstrators) in a standardized experimental environment, using a playground setup. At both test ages, we found evidence for emotional contagion as observer ravens showed an increase of locomotion and social play after we provided the demonstrator(s) with the playground setup, but no significant changes in the amount of object play. Hence, observers did not copy motor patterns from demonstrator(s) but engaged in other forms of play. Our findings speak for a transfer of a general mood state in the context of play in ravens as young as 3 months and against behavioral mimicry as a precondition for emotional contagion.

RevDate: 2021-04-14
CmpDate: 2021-04-12

Gallego-Abenza M, Blum CR, T Bugnyar (2021)

Who is crying wolf? Seasonal effect on antipredator response to age-specific alarm calls in common ravens, Corvus corax.

Learning & behavior, 49(1):159-167.

Communication about threats including those posed by the presence of predators occurs mainly through acoustic signals called alarm calls. The comprehension of these calls by receivers and their rapid antipredator response are crucial in terms of survival. However, to avoid overreaction, individuals should evaluate whether or not an antipredator response is needed by paying attention to who is calling. For instance, we could expect adults to be more experienced with predator encounters than juveniles and thus elicit stronger antipredator responses in others when alarming. Similarly, we could expect a stronger response to alarm calls when more than one individual is calling. To test these assumptions, we applied a playback experiment to wild ravens, in which we manipulated the age class (adult or juvenile) and the number (one or two) of the callers. Our results revealed a seasonal effect of age class but no effect of number of callers. Specifically, the ravens responded with stronger antipredator behaviour (vigilance posture) towards alarm calls from adults as compared to juveniles in summer and autumn, but not in spring. We discuss alternative interpretations for this unexpected seasonal pattern and argue for more studies on call-based communication in birds to understand what type of information is relevant under which conditions.

RevDate: 2021-06-22
CmpDate: 2021-06-22

Blakey ML (2021)

Understanding racism in physical (biological) anthropology.

American journal of physical anthropology, 175(2):316-325.

The mainstream of American physical anthropology began as racist and eugenical science that defended slavery, restricted "non-Nordic" immigration, and justified Jim Crow segregation. After World War II, the field became more anti-racial than anti-racist. It has continued as a study of natural influences on human variation and thus continues to evade the social histories of inequitable biological variation. Also reflecting its occupancy of white space, biological anthropology continues to deny its own racist history and marginalizes the contributions of Blacks. Critical disciplinary history and a shift toward biocultural studies might begin an anti-racist human biology.

RevDate: 2020-12-29

Kaplan G (2020)

Of Great Apes and Magpies: Initiations into Animal Behaviour.

Animals : an open access journal from MDPI, 10(12):.

This paper presents three case studies of exceptional human encounters with animals. These particular examples were selected because they enabled analysis of the underlying reasons that led the human participants to respond in new ways to their animal counterparts. The question asked here is whether sudden insights into the needs and abilities of an animal arises purely from an anthropocentric position as empathy because of genetic closeness (e.g., chimpanzees) or is something else and whether new insights can be applied to other phylogenetic orders not close to us, e.g., birds, and change research questions and implicit prejudices and stereotypes. Particularly in avian species, phylogenetically distant from humans, the prejudices (anthroprocentric position) and the belief in human uniqueness (human exceptionalism) might be greater than in the reactions to primates. Interestingly, in studies of great apes, contradictory opinions and controversies about cognitive abilities, especially when compared with humans, tend to be pronounced. Species appropriateness in test designs are desirable present and future goals but here it is suggested how different experiences can also lead to different questions that explode the myth of human uniqueness and then arrive at entirely different and new results in cognitive and affective abilities of the species under investigation.

RevDate: 2020-12-15
CmpDate: 2020-12-15

Mori A, R Bertani (2020)

Revision and cladistic analysis of Psalistops Simon, 1889, Trichopelma Simon, 1888 and Cyrtogrammomma Pocock, 1895 (Araneae: Theraphosidae) based on a cladistic analysis of relationships of Theraphosidae, Barychelidae and Paratropididae.

Zootaxa, 4873(1):zootaxa.4873.1.1 pii:zootaxa.4873.1.1.

The genera Psalistops Simon, 1889, Trichopelma, Simon, 1888 and Cyrtogrammomma Pocock, 1895 are revised and included in cladistics analyses including almost all species of these genera. In order to test previous morphological hypotheses on the relationships of Barychelidae, Paratropididae and Theraphosidae and because of the controversial taxonomic position of Psalistops and Trichopelma, a set of terminal taxa representing all subfamilies of Paratropididae (Paratropidinae, Glabropelmatinae), Barychelidae (Barychelinae, Sasoninae, Trichopelmatinae) and most theraphosid subfamilies were included, as well as a diplurid, a nemesiid, and a pycnothelid, the later used to root the cladogram. The matrix with 66 terminal taxa, 2 continuous and 93 discrete characters was analysed with TNT 1.5. We found that Trichopelmatinae is not a monophyletic group, and Psalistops is transferred to Theraphosidae, as well as the barychelid genus Cyrtogrammomma and the paratropidid genus Melloina Brignoli. Cyrtogrammomma was retrieved as the sister group of Trichopelma, and Melloina as the sister group of Holothele Karsch. Psalistops was retrieved as the sister group of Reichlingia Rudloff, and the clade with these two genera is the most basal in Theraphosidae. Barychelidae was found to be monophyletic and the sister group of Theraphosidae. Paratropididae was retrieved as the sister group of Barychelidae + Theraphosidae. The relationship and possible synapomorphies of the three families are herein discussed. This is the first time since Raven (1985) that representatives of all barychelid (Barychelinae, Sasoninae, Trichopelmatinae), paratropidid (Paratropidinae, Glabropelmatinae) and most theraphosid subfamilies have been included in a morphological cladistic analysis. Psalistops comprises two species, P. melanopygius Simon, 1889 (type species) and P. colombianus sp. nov. Psalistops montigena Simon, 1889, P. tigrinus Simon, 1889 and P. zonatus Simon, 1889 are synonymized with P. melanopygius Simon, 1889. Psalistops fulvus Bryant, 1948, P. hispaniolensis Wunderlich, 1988 (fossil), P. maculosus Bryant, 1948, P. venadensis Valerio, 1986 and P. steini (Simon, 1889) are transferred to Trichopelma. Psalistops gasci Maréchal, 1996 is transferred to Hapalopus Ausserer (Theraphosidae); P. opifex (Simon, 1889) and P. solitarius (Simon, 1889) are transferred to Schismatothele Karsch, 1879 (Theraphosidae). Schismatothele solitarius (Simon, 1889) n. comb. is synonymized with Schismatothele lineata Karsch, 1879, n. syn. Psalistops nigrifemuratus Mello-Leitão, 1939 is probably a nemesiid or pycnothelid, and herein considered as nomen dubium in Pycnothelidae. Trichopelma comprises 22 species: Trichopelma nitidum Simon, 1888 (type species), T. coenobita (Simon, 1889), T. steini (Simon, 1889), T. affine (Simon, 1892), T. cubanum (Simon, 1903), T. maculatum (Banks, 1906), T. zebra (Petrunkevitch, 1925), T. banksia Özdikmen Demir, 2012, T. insulanum (Petrunkevitch, 1926), T. fulvus (Bryant, 1948) n. comb., T. laselva Valerio, 1986, T. venadensis (Valerio, 1986) n. comb., T. huffi sp. nov., T. gabrieli sp. nov., T. tostoi sp. nov., T. goloboffi sp. nov., T. juventud sp. nov., T. laurae sp. nov., T.bimini sp. nov., T. loui sp. nov., T. platnicki sp. nov., and T. hispaniolensis Wunderlich, 1988 n. comb. (fossil). Trichopelma maculosus (Bryant, 1948) n. comb. is synonymized with P. fulvus Bryant, 1948; T. corozalis (Petrunkevitch, 1929) is synonymized with T. insulanum (Petrunkevitch, 1926). Trichopelma astutum Simon, 1889 is transferred to Euthycaelus Simon, 1889, and T. maddeni Esposito Agnarsson, 2014 to Holothele Karsch, 1879 (Theraphosidae). Trichopelma flavicomum Simon, 1891 is transferred to Neodiplothele (Barychelidae, Sasoninae). The species T. illetabile Simon, 1888, T. spinosum (Franganillo, 1926), T. scopulatum (Fischel, 1927) and T. eucubanum Özdikmen Demir, 2012 are considered as nomina dubia. Cyrtogrammomma comprises two species: C. monticola Pocock, 1895 (type species) and C. raveni sp. nov.

RevDate: 2021-06-21
CmpDate: 2021-06-21

Dussex N, Kutschera VE, Wiberg RAW, et al (2021)

A genome-wide investigation of adaptive signatures in protein-coding genes related to tool behaviour in New Caledonian and Hawaiian crows.

Molecular ecology, 30(4):973-986.

Very few animals habitually manufacture and use tools. It has been suggested that advanced tool behaviour co-evolves with a suite of behavioural, morphological and life history traits. In fact, there are indications for such an adaptive complex in tool-using crows (genus Corvus species). Here, we sequenced the genomes of two habitually tool-using and ten non-tool-using crow species to search for genomic signatures associated with a tool-using lifestyle. Using comparative genomic and population genetic approaches, we screened for signals of selection in protein-coding genes in the tool-using New Caledonian and Hawaiian crows. While we detected signals of recent selection in New Caledonian crows near genes associated with bill morphology, our data indicate that genetic changes in these two lineages are surprisingly subtle, with little evidence at present for convergence. We explore the biological explanations for these findings, such as the relative roles of gene regulation and protein-coding changes, as well as the possibility that statistical power to detect selection in recently diverged lineages may have been insufficient. Our study contributes to a growing body of literature aiming to decipher the genetic basis of recently evolved complex behaviour.

RevDate: 2021-05-20
CmpDate: 2021-05-20

Pika S, Sima MJ, Blum CR, et al (2020)

Ravens parallel great apes in physical and social cognitive skills.

Scientific reports, 10(1):20617.

Human children show unique cognitive skills for dealing with the social world but their cognitive performance is paralleled by great apes in many tasks dealing with the physical world. Recent studies suggested that members of a songbird family-corvids-also evolved complex cognitive skills but a detailed understanding of the full scope of their cognition was, until now, not existent. Furthermore, relatively little is known about their cognitive development. Here, we conducted the first systematic, quantitative large-scale assessment of physical and social cognitive performance of common ravens with a special focus on development. To do so, we fine-tuned one of the most comprehensive experimental test-batteries, the Primate Cognition Test Battery (PCTB), to raven features enabling also a direct, quantitative comparison with the cognitive performance of two great ape species. Full-blown cognitive skills were already present at the age of four months with subadult ravens' cognitive performance appearing very similar to that of adult apes in tasks of physical (quantities, and causality) and social cognition (social learning, communication, and theory of mind). These unprecedented findings strengthen recent assessments of ravens' general intelligence, and aid to the growing evidence that the lack of a specific cortical architecture does not hinder advanced cognitive skills. Difficulties in certain cognitive scales further emphasize the quest to develop comparative test batteries that tap into true species rather than human specific cognitive skills, and suggest that socialization of test individuals may play a crucial role. We conclude to pay more attention to the impact of personality on cognitive output, and a currently neglected topic in Animal Cognition-the linkage between ontogeny and cognitive performance.

RevDate: 2021-04-12
CmpDate: 2021-04-12

Vernouillet A, Casidsid HJM, DM Kelly (2021)

Conspecific presence, but not pilferage, influences pinyon jays' (Gymnorhinus cyanocephalus) caching behavior.

Learning & behavior, 49(1):23-35.

Caching species store food when plentiful to ensure availability when resources are scarce. These stores may be at risk of pilferage by others present at the time of caching. Cachers may reduce the risk of loss by using information from the social environment to engage in behaviors to secure the resource-cache protection strategies. Here, we examined whether pinyon jays, a highly social corvid, use information from the social environment to modify their caching behavior. Pinyon jays were provided with pine seeds to cache in two visually distinct trays. The cacher could be observed by a non-pilfering conspecific, a pilfering conspecific, or an inanimate heterospecific located in an adjoining cage compartment, or the cacher could be alone. After caching, the pilfered tray was placed in the adjoining compartment where caches were either pilfered (pilfering conspecific and inanimate heterospecific conditions) or remained intact (non-pilfering conspecific and alone conditions). The safe tray was placed in a visible, but inaccessible, location. Overall, pinyon jays reduced the number of pine seeds cached in the pilfered tray when observed, compared with caching alone. However, their caching behavior did not differ between the pilfering conspecific and the non-pilfering conspecific conditions. These results suggest that either pinyon jays were unable to discriminate between the pilfering and non-pilfering conspecifics, or they generalized their experience of risk from the pilfering conspecific to the non-pilfering conspecific. Thus, we report evidence that pinyon jays use cache protection strategies to secure their resources when observed, but respond similarly when observed by pilfering and non-pilfering conspecifics.

RevDate: 2020-11-24

Wagener L, A Nieder (2020)

Categorical Auditory Working Memory in Crows.

iScience, 23(11):101737.

The ability to group sensory data into behaviorally meaningful classes and to maintain these perceptual categories active in working memory is key to intelligent behavior. Here, we show that carrion crows, highly vocal and cognitively advanced corvid songbirds, possess categorical auditory working memory. The crows were trained in a delayed match-to-category task that required them to flexibly match remembered sounds based on the upward or downward shift of the sounds' frequency modulation. After training, the crows instantaneously classified novel sounds into the correct auditory categories. The crows showed sharp category boundaries as a function of the relative frequency interval of the modulation. In addition, the crows generalized frequency-modulated sounds within a category and correctly classified novel sounds kept in working memory irrespective of other acoustic features of the sound. This suggests that crows can form and actively memorize auditory perceptual categories in the service of cognitive control of their goal-directed behaviors.

RevDate: 2020-11-17

Blum CR, Fitch WT, T Bugnyar (2020)

Rapid Learning and Long-Term Memory for Dangerous Humans in Ravens (Corvus corax).

Frontiers in psychology, 11:581794.

Like many predatory species, humans have pronounced individual differences in their interactions with potential prey: some humans pose a lethal threat while others may provide valuable resources. Recognizing individual humans would thus allow prey species to maximize potential rewards while ensuring survival. Previous studies on corvids showed they can recognize and remember individual humans. For instance, wild American crows produced alarm calls toward specifically masked humans up to 2.7 years after those humans had caught and ringed them while wearing that mask. However, individual behavior of the crows or the impact of social features on their responses, was hardly examined. Here, we studied predator learning and social effects on responses, using a similar method, in captive common ravens (Corvus corax). We investigated learning and the impact of key social components on individual reactions to artificial predators. Human experimenters wore two types of masks while walking past two raven aviaries. In four training trials, the "dangerous" mask was presented while carrying a dead raven, whereas the "neutral" mask was presented empty-handed. Between every training trial and in all following trials, we presented both masks without dead ravens. We assessed the subjects' (i) learning speed, (ii) selective long-term response, and (iii) potential effects of social dynamics on individual alarm calling frequency. Ravens learned quickly (often based on the first trial), and some individuals distinguished the dangerous from the neutral mask for the next 4 years. Despite having received the same amount and quality of exposure to the dangerous mask, we found pronounced individual differences in alarm calling that were fairly consistent across test trials in socially stable situations: dominance, but not sex explained individual differences in alarm responses, indicating the potential use of alarm calls as "status symbols." These findings fit to those in wild bird populations and dominant individuals signaling their quality. Changes in the individuals' participation and intensity of alarm calling coincided with changes in group composition and pair formation, further supporting the role of social context on ravens' alarm calling.

RevDate: 2021-03-22
CmpDate: 2021-03-22

Shahhosseini N, Frederick C, Racine T, et al (2021)

Modeling host-feeding preference and molecular systematics of mosquitoes in different ecological niches in Canada.

Acta tropica, 213:105734.

Several mosquito-borne viruses (mobovirus) cause infections in Canada. Ecological data on mosquito species and host range in Canada remains elusive. The main aim of the current study is to determine the host range and molecular systematics of mosquito species in Canada. Mosquitoes were collected using BG-Sentinel traps and aspirators at 10 trapping sites in Canada during 2018 and 2019. Mosquitoes collected were identified via morphology and molecular techniques. Mosquito sequences were aligned by MUSCLE algorithm and evolutionary systematics were drawn using MEGA and SDT software. Moreover, the source of blood meals was identified using a DNA barcoding technique. A total of 5,708 female mosquitoes over 34 different taxa were collected. DNA barcodes and evolutionary tree analysis confirmed the identification of mosquito species in Canada. Of the total collected samples, 201 specimens were blood-fed female mosquitoes in 20 different taxa. Four mosquito species represented about half (51.47%) of all collected blood-fed specimens: Aede cinereus (39 specimens, 19.11%), Aedes triseriatus (23, 11.27%), Culex pipiens (22, 10.78%), and Anopheles punctipennis (21, 10.29%). The most common blood meal sources were humans (49 mosquito specimens, 24% of all blood-fed mosquito specimen), pigs (44, 21.5%), American red squirrels (28, 13.7%), white-tailed deers (28, 13.7%), and American crows (16, 7.8%). Here, we present the first analysis of the host-feeding preference of different mosquito species in Canada via molecular techniques. Our results on mosquito distribution and behavior will aid in the development of effective mitigation and control strategies to prevent or reduce human/animal health issues in regards to moboviruses.

RevDate: 2021-03-29
CmpDate: 2021-03-29

Armenteros JA, Caro J, SÁnchez-GarcÍa C, et al (2021)

Do non-target species visit feeders and water troughs targeting small game? A study from farmland Spain using camera-trapping.

Integrative zoology, 16(2):226-239.

Provision of food and water is a widespread tool implemented around the world for the benefit of game and other wildlife, but factors affecting the use of food and water by non-target species are poorly known. We evaluated visits to feeders and water troughs by non-game species using camera-traps in two separate areas of Spain. Feeders and water troughs were either "protected" (when surrounded by more than 50% of shrubs/forest) or "open" (in the opposite case). A total of 18 948 photos from 5344 camera-trapping days depicted animals, and 75 species were identified. Feeders and water troughs were visited by target species (partridges and lagomorphs, 55.3% of visits) and non-target species (44.7% of visits). Among the latter, corvids were the most common (46.1% of visits), followed by rodents (26.8%), other birds (23.6%, mainly passerines), columbids (1.9%), and other species at minor percentages. The highest proportion of visiting days to feeders and water troughs was from corvids (0.173) followed by other-birds (0.109) and rodents (0.083); the lowest proportion was recorded for columbids (0.016). Use intensity and visit frequency of water troughs tripled that recorded in feeders, and visits to open feeders/troughs were approximately twice those to protected ones. In summary: feeders and water troughs targeting small game species are also used regularly by non-target ones; they should be set close to cover to optimize their use by non-target species that are not competitors of target species (though corvids may visit them); water availability should be prioritized where drought periods are expected.

RevDate: 2021-01-04
CmpDate: 2021-01-04

Boeckle M, Schiestl M, Frohnwieser A, et al (2020)

New Caledonian crows plan for specific future tool use.

Proceedings. Biological sciences, 287(1938):20201490.

The ability to plan for future events is one of the defining features of human intelligence. Whether non-human animals can plan for specific future situations remains contentious: despite a sustained research effort over the last two decades, there is still no consensus on this question. Here, we show that New Caledonian crows can use tools to plan for specific future events. Crows learned a temporal sequence where they were (a) shown a baited apparatus, (b) 5 min later given a choice of five objects and (c) 10 min later given access to the apparatus. At test, these crows were presented with one of two tool-apparatus combinations. For each combination, the crows chose the right tool for the right future task, while ignoring previously useful tools and a low-value food item. This study establishes that planning for specific future tool use can evolve via convergent evolution, given that corvids and humans shared a common ancestor over 300 million years ago, and offers a route to mapping the planning capacities of animals.

RevDate: 2021-03-03
CmpDate: 2021-03-03

Horn L, Bugnyar T, Griesser M, et al (2020)

Sex-specific effects of cooperative breeding and colonial nesting on prosociality in corvids.

eLife, 9:.

The investigation of prosocial behavior is of particular interest from an evolutionary perspective. Comparisons of prosociality across non-human animal species have, however, so far largely focused on primates, and their interpretation is hampered by the diversity of paradigms and procedures used. Here, we present the first systematic comparison of prosocial behavior across multiple species in a taxonomic group outside the primate order, namely the bird family Corvidae. We measured prosociality in eight corvid species, which vary in the expression of cooperative breeding and colonial nesting. We show that cooperative breeding is positively associated with prosocial behavior across species. Also, colonial nesting is associated with a stronger propensity for prosocial behavior, but only in males. The combined results of our study strongly suggest that both cooperative breeding and colonial nesting, which may both rely on heightened social tolerance at the nest, are likely evolutionary pathways to prosocial behavior in corvids.

RevDate: 2021-01-26
CmpDate: 2021-01-26

Themelin M, Ribic CA, Melillo-Sweeting K, et al (2020)

A new approach to the study of relationship quality in dolphins: Framework and preliminary results.

Behavioural processes, 181:104260.

Proximity and synchronous behaviours from surface observations have been used to measure association patterns within and between dolphin dyads. To facilitate an investigation of relationship quality in dolphins, we applied a method used for primates and ravens that examined three main components to describe relationships: value, security, and compatibility. Using pilot data from long-term research of two study populations for this preliminary assessment, these three components were extracted from PCA of eight behavioural variables with more than 80 % variance accounted for in both study groups. Only pair swim position differed between groups. Although value, security, and compatibility are abstract terms, each is based on behaviours identified as important in dolphin social life, at least for these two populations. Examining relationship quality in dolphins with a method used to illustrate dyadic differences for primates and ravens allows for a quantitative, comparative assessment of sociality across disparate taxa. Although these species are diverse in their anatomies and in their social habitats (e.g., aquatic, terrestrial, aerial), they may well share the basic societal building blocks in the factors affecting how relationships are formed. We discuss how an examination of these behavioural variables facilitates understanding relationship quality in dolphins, as well as how dolphin relationships fit into the context of social animals' society.

RevDate: 2020-12-14
CmpDate: 2020-12-14

Lin Y, Zhang X, Huang Q, et al (2020)

The Prevalence of Dyslexia in Primary School Children and Their Chinese Literacy Assessment in Shantou, China.

International journal of environmental research and public health, 17(19):.

The epidemiological studies of Chinese developmental dyslexia (DD) in China are still limited. In addition, literacy assessment has seldom been performed for children with dyslexia, due to lack of uniform assessment tools. This study was aimed at investigating the prevalence rate of children with dyslexia, and to evaluate their Chinese reading ability. A total of 2955 students aged 7-12 years were enrolled by randomized cluster sampling. The study was divided into three stages. In stage I, all participating students were asked to finish the Combined Raven Test (CRT) and Chinese Vocabulary Test and Assessment Scale. In stage II, the Chinese teachers and parents of the children with suspected dyslexia were interviewed by psychiatrists, and finished the Dyslexia Checklist for Chinese Children (DCCC). In stage III, these children were evaluated by child psychiatrists for the diagnosis with or without dyslexia, according to the fifth edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-5), and their Chinese literacy was further evaluated by using the Chinese Reading Ability Test (CRAT). The prevalence rate of children with dyslexia was 5.4% in Shantou city, 8.4% in boys and 2.3% in girls, with a gender ratio of 3.7:1.0. Children with dyslexia scored lower in all the five subscales of the CRAT tests. including phonological awareness, morphological awareness, rapid automatized naming, orthographic awareness, and reading ability than the control group (all p < 0.001). This study suggested that the prevalence rate of Chinese dyslexia in Shantou city is roughly equivalent to that previously reported in China. Children with dyslexia have a relatively lower Chinese reading ability in all assessments.

RevDate: 2021-01-19
CmpDate: 2021-01-19

Massen JJM, Haley SM, T Bugnyar (2020)

Azure-winged magpies' decisions to share food are contingent on the presence or absence of food for the recipient.

Scientific reports, 10(1):16147.

Helping others is a key feature of human behavior. However, recent studies render this feature not uniquely human, and describe discoveries of prosocial behavior in non-human primates, other social mammals, and most recently in some bird species. Nevertheless, the cognitive underpinnings of this prosociality; i.e., whether animals take others' need for help into account, often remain obscured. In this study, we take a first step in investigating prosociality in azure-winged magpies by presenting them with the opportunity to share highly desired food with their conspecifics i) in a situation in which these conspecifics had no such food, ii) in a situation in which they too had access to that highly desired food, and iii) in an open, base-line, situation where all had equal access to the same food and could move around freely. We find that azure-winged magpies regularly share high-value food items, preferably with, but not restricted to, members of the opposite sex. Most notably, we find that these birds, and specifically the females, seem to differentiate between whether others have food or do not have food, and subsequently cater to that lack. Begging calls by those without food seem to function as cues that elicit the food-sharing, but the response to that begging is condition-dependent. Moreover, analyses on a restricted dataset that excluded those events in which there was begging showed exactly the same patterns, raising the possibility that the azure-winged magpies might truly notice when others have access to fewer resources (even in the absence of vocal cues). This sharing behavior could indicate a high level of social awareness and prosociality that should be further investigated. Further studies are needed to establish the order of intentionality at play in this system, and whether azure-winged magpies might be able to attribute desire states to their conspecifics.

RevDate: 2021-01-26
CmpDate: 2021-01-26

Hunt GR (2021)

New Caledonian crows' basic tool procurement is guided by heuristics, not matching or tracking probe site characteristics.

Animal cognition, 24(1):177-191.

Contrasting findings made it unclear what cognitive processes New Caledonian crows use to procure suitable tools to solve tool tasks. Most previous studies suggested that their tool procurement is achieved by either trial and error or a simple heuristic. The latter provides a fast and cognitively efficient method for stable, routinized behaviour based on past experience with little or no deliberate decision-making. However, early papers by Chappell and Kacelnik reported that two New Caledonian crows procured tools after closely assessing the tool characteristics required for the task, thus using deliberate decision-making, or a 'customized strategy'. Here, I tested eight New Caledonian crows to determine their default behaviour in basic tool procurement tasks as a check on whether or not they use customized strategies. I used two rigorous experiments closely based on Chappell and Kacelnik's experiments. The crows did not use a customized strategy in either experiment, but their behaviour was clearly consistent with tool procurement predominantly guided by a familiarity heuristic. I discuss potential methodological issues that may have led to different conclusions in Chappell and Kacelnik's studies. Heuristic-guided, routinized behaviour in tool procurement has potential implications for understanding how standardization occurs in the early evolution of complex tool manufacture, both in New Caledonian crows and early humans.

RevDate: 2021-04-27
CmpDate: 2021-04-27

Hswen Y, Qin Q, Williams DR, et al (2020)

The relationship between Jim Crow laws and social capital from 1997-2014: A 3-level multilevel hierarchical analysis across time, county and state.

Social science & medicine (1982), 262:113142.

INTRODUCTION: Jim Crow laws in the United States promoted racial prejudice, which may have reduced social capital. Our study tests the relationship between Jim Crow laws and social capital.

METHODS: We conducted 3-level multilevel hierarchical modeling to study differences in the stock of social capital for 1997, 2005, 2009 in Jim Crow states compared to states without Jim Crow laws. We examined the moderation effects of county level median income, percent Black and percent with high school education and Jim Crow laws on social capital.

RESULTS: Jim Crow laws significantly reduced stock of social capital across 1997, 2005, 2009. The model was robust to the inclusion of random county, states, time and fixed county and state level covariates for median income, percent Black and percent with high school education. The largest percent of between state variations explained for fixed variables was from the addition of Jim Crow laws with 2.86%. These results demonstrate that although Jim Crow laws were abolished in 1965, the effects of racial segregation appear to persist through lower social connectiveness, community and trust. A positive moderation effect was seen for median income and percent Black with Jim Crow laws on social capital.

DISCUSSION: Our study supports a negative association between Jim Crow laws and reduction in the stock of social capital. This may be attributed to the fracturing of trust, reciprocity and collective action produced by legal racial segregation. Findings from this study offer insight on the potential impacts of historical policies on the social structure of a community. Future research is necessary to further identify the mechanistic pathways and develop interventions to improve social capital.

RevDate: 2020-12-14
CmpDate: 2020-12-04

Zhao W, Li H, Zhu X, et al (2020)

Effect of Birdsong Soundscape on Perceived Restorativeness in an Urban Park.

International journal of environmental research and public health, 17(16):.

Natural soundscapes have beneficial effects on the perceived restorativeness of an environment. This study examines the effect of birdsong, a common natural soundscape, on perceived restorativeness in Harbin Sun Island Park in China. Eight sites were selected and a series of questionnaire surveys on perceived restorativeness soundscape scale (PRSS) of four birdsong types were conducted during summer and winter. Two-hundred and forty respondents participated in this survey. Analysis of the survey results shows that different types of birdsong have different perceived restorativeness effects in different seasons. Crow birdsong has the worst effect on the perceived restorativeness in both summer and winter. Moreover, sound comfort and preference are significantly associated with the perceived restorativeness. The perceived restorativeness soundscape is best when birdsong is at a height of 4 m rather than 0.5 m or 2 m. The demographic/social factors of age, education, and stress level are all correlated with perceived restorativeness. There are suggestions for urban park design, especially with constructed natural elements. Creating a suitable habitat for multiple species of birds will improve perceived restorativeness. Moreover, appropriate activities should be provided in city parks to ensure restorativeness environments, especially for subjects with high levels of education and stress.

RevDate: 2020-09-23
CmpDate: 2020-09-23

Engel N, Végvári Z, Rice R, et al (2020)

Incubating parents serve as visual cues to predators in Kentish plover (Charadrius alexandrinus).

PloS one, 15(7):e0236489.

Ground-nesting birds face many challenges to reproduce successfully, with nest predation being the main cause of reproductive failure. Visual predators such as corvids and egg-eating raptors, are among the most common causes of nest failure; thus, parental strategies that reduce the risk of visual nest predation should be favored by selection. To date, most research has focused on egg crypsis without considering adult crypsis, although in natural circumstances the eggs are covered by an incubating parent most of the time. Here we use a ground-nesting shorebird, the Kentish plover (Charadrius alexandrinus) as model species to experimentally test whether decoy parents influence nest predation. Using artificial nests with a male decoy, a female decoy or no decoy, we found that the presence of a decoy increased nest predation (N = 107 nests, p < 0.001). However, no difference was found in predation rates between nests with a male versus female decoy (p > 0.05). Additionally, we found that nests in densely vegetated habitats experienced higher survival compared to nests placed in sparsely vegetated habitats. Nest camera images, predator tracks and marks left on eggs identified the brown-necked raven (Corvus ruficollis) as the main visual nest predator. Our study suggests that the presence of incubating parents may enhance nest detectability to visual predators. However, parents may reduce the predation risk by placing a nest in sites where they are covered by vegetation. Our findings highlight the importance of nest site selection not only regarding egg crypsis but also considering incubating adult camouflage.

RevDate: 2020-09-16
CmpDate: 2020-09-16

Bravo C, Pays O, Sarasa M, et al (2020)

Revisiting an old question: Which predators eat eggs of ground-nesting birds in farmland landscapes?.

The Science of the total environment, 744:140895.

Nest predation is a major cause of reproductive failure in birds, but predator identity often remains unknown. Additionally, although corvids are considered major nest predators in farmland landscapes, whether breeders or floaters are involved remains contentious. In this study, we aimed to identify nest predators using artificial nests, and test whether territorial or non-breeders carrion crow (Corvus corone) and Eurasian magpie (Pica pica) were most likely involved. We set up an experiment with artificial ground nests (n = 1429) in farmland landscapes of western France, and assessed how different combinations of egg size and egg material (small plasticine egg, large plasticine egg, quail and natural hen eggs) might influence predation rates and predator species involved. Nest predators were identified using remotely triggered cameras and marks left in plasticine eggs. Corvids were by far the predators most involved (almost 80% of all predation events), independent of egg type. Carrion crows alone were involved in 60% of cases. Probability of predation increased with egg size, and predation rate was higher for natural than for artificial eggs, suggesting that, in addition to egg size, predators might perceive plasticine and natural eggs differently. Predation rates of artificial nests by corvids were related significantly to corvid abundance, and far more to breeder than floater abundances, for both carrion crows and magpies. This study emphasizes the importance of identifying predators at species level, and considering their social status when assessing corvid abundance impact on prey population dynamics. Combining camera traps and plasticine eggs can achieve this objective. Given the high predation rate by carrion crows, a better understanding of landscape-mediated changes in predator diet seems mandatory to design mitigation schemes able to confront ecological challenges raised by generalist predators.

RevDate: 2021-04-19
CmpDate: 2021-04-19

Lee CY, Peralta-Sánchez JM, Martínez-Bueno M, et al (2020)

The gut microbiota of brood parasite and host nestlings reared within the same environment: disentangling genetic and environmental effects.

The ISME journal, 14(11):2691-2702.

Gut microbiota are essential for host health and survival, but we are still far from understanding the processes involved in shaping their composition and evolution. Controlled experimental work under lab conditions as well as human studies pointed at environmental factors (i.e., diet) as the main determinant of the microbiota with little evidence of genetic effects, while comparative interspecific studies detected significant phylogenetic effects. Different species, however, also differ in diet, feeding behavior, and environmental characteristics of habitats, all of which also vary interspecifically, and, therefore, can potentially explain most of the detected phylogenetic patterns. Here, we take advantage of the reproductive strategy of avian brood parasites and investigate gut microbiotas (esophageal (food and saliva) and intestinal) of great spotted cuckoo (Clamator glandarius) and magpie (Pica pica) nestlings that grow in the same nests. We also estimated diet received by each nestling and explored its association with gut microbiota characteristics. Although esophageal microbiota of magpies and great spotted cuckoos raised within the same environment (nest) did not vary, the microbiota of cloacal samples showed clear interspecific differences. Moreover, diet of great spotted cuckoo and magpie nestlings explained the microbiota composition of esophageal samples, but not of cloaca samples. These results strongly suggest a genetic component determining the intestinal microbiota of host and parasitic bird species, indicating that interspecific differences in gut morphology and physiology are responsible for such interspecific differences.

RevDate: 2020-09-04
CmpDate: 2020-09-04

Wei W, Zhen Q, Tang Z, et al (2020)

Risk assessment in the plateau pika (Ochotona curzoniae): intensity of behavioral response differs with predator species.

BMC ecology, 20(1):41.

BACKGROUND: The ability of a prey species to assess the risk that a predator poses can have important fitness advantages for the prey species. To better understand predator-prey interactions, more species need to be observed to determine how prey behavioral responses differ in intensity when approached by different types of predators. The plateau pika (Ochotona curzoniae) is preyed upon by all predators occurring in its distribution area. Therefore, it is an ideal species to study anti-predator behavior. In this study, we investigated the intensity of anti-predator behavior of pikas in response to visual cues by using four predator species models in Maqu County on the eastern Qinghai-Tibetan Plateau.

RESULTS: The behavioral response metrics, such as Flight Initiation Distance (FID), the hiding time and the percentage of vigilance were significantly different when exposed to a Tibetan fox, a wolf, a Saker falcon and a large-billed crow, respectively. Pikas showed a stronger response to Saker falcons compared to any of the other predators.

CONCLUSIONS: Our results showed that pikas alter their behavioral (such as FID, the hiding time and the vigilance) response intensity to optimally balance the benefits when exposed to different taxidermy predator species models. We conclude that pikas are able to assess their actual risk of predation and show a threat-sensitive behavioral response.

RevDate: 2020-12-22
CmpDate: 2020-12-22

Mohamed Benkada A, Pontier F, V Dufour (2020)

Conflict management in rooks (Corvus frugilegus): Victims do not display post-conflict affiliation but avoid their former aggressor.

Behavioural processes, 179:104198.

Many social species use post-conflict behaviors to mitigate the consequences of conflicts. One of these behaviors is the victim's affiliation with its former opponent following conflict in an attempt to restore the damaged relationship. The victim can also affiliate with a third party. Affiliation with former opponents and third parties also alleviates stress. Studies of conflict management strategies in birds mostly concern corvids, and more specifically rooks (Corvus frugilegus). In this colonial pair-bonded species, the most valuable relationship is with the mate. It is rarely conflictual, meaning that there is generally no need for any post-conflict affiliation. However, conflicts occur with other social partners, and victims may primarily use third-party affiliation to avoid renewed aggression after conflicts. Previous studies of rooks failed to show a protective role of third-party affiliations for rook victims. The present study seeks to further investigate the use and efficiency of these conflict management strategies from the victim's perspective. We recorded conflicts and post-conflict behaviors in captive rooks using the standard post-conflict matched control comparison method. Victims did not affiliate with their former opponent or with third parties after conflict, but rather avoided their former aggressor, thus successfully limiting the risk of renewed aggression. Post-conflict affiliations are not observed in all rook colonies, suggesting that avoidance of the former aggressor may be a more commonly used strategy than previously thought.

RevDate: 2021-04-12
CmpDate: 2021-04-12

Baciadonna L, Cornero FM, Emery NJ, et al (2021)

Convergent evolution of complex cognition: Insights from the field of avian cognition into the study of self-awareness.

Learning & behavior, 49(1):9-22.

Pioneering research on avian behaviour and cognitive neuroscience have highlighted that avian species, mainly corvids and parrots, have a cognitive tool kit comparable with apes and other large-brained mammals, despite conspicuous differences in their neuroarchitecture. This cognitive tool kit is driven by convergent evolution, and consists of complex processes such as casual reasoning, behavioural flexibility, imagination, and prospection. Here, we review experimental studies in corvids and parrots that tested complex cognitive processes within this tool kit. We then provide experimental examples for the potential involvement of metacognitive skills in the expression of the cognitive tool kit. We further expand the discussion of cognitive and metacognitive abilities in avian species, suggesting that an integrated assessment of these processes, together with revised and multiple tasks of mirror self-recognition, might shed light on one of the most highly debated topics in the literature-self-awareness in animals. Comparing the use of multiple assessments of self-awareness within species and across taxa will provide a more informative, richer picture of the level of consciousness in different organisms.

RevDate: 2020-07-03

Boucherie PH, Blum C, T Bugnyar (2020)

Effect of rearing style on the development of social behaviour in young ravens (Corvus corax).

Ethology : formerly Zeitschrift fur Tierpsychologie, 126(6):595-609.

Early social experiences can affect the development and expression of individual social behaviour throughout life. In particular, early-life social deprivations, notably of parental care, can later have deleterious consequences. We can, therefore, expect rearing procedures such as hand-raising-widely used in ethology and socio-cognitive science-to alter the development of individual social behaviour. We investigated how the rearing style later affected (a) variation in relationship strength among peers and (b) individuals' patterns of social interactions, in three captive groups of juvenile non-breeders consisting of either parent-raised or hand-raised birds, or a mix of both rearing styles. In the three groups, irrespectively of rearing style: strongest relationships (i.e., higher rates of association and affiliations) primarily emerged among siblings and familiar partners (i.e., non-relatives encountered in early life), and mixed-sex and male-male partners established relationships of similar strength, indicating that the rearing style does not severely affect the quality and structure of relationships in young ravens. However, compared to parent-raised ravens, hand-raised ravens showed higher connectedness, i.e., number of partners with whom they mainly associated and affiliated, but formed on average relationships of lower strength, indicating that social experience in early life is not without consequences on the development of ravens' patterns of social interaction. The deprivation of parental care associated with the presence of same-age peers during hand-raising seemed to maximize ravens' propensity to interact with others, indicating that besides parents, interactions with same-age peers matter. Opportunities to interact with, and socially learn from peers, might thus be the key to the acquisition of early social competences in ravens.

RevDate: 2021-02-11
CmpDate: 2021-02-11

Chakarov N, Kampen H, Wiegmann A, et al (2020)

Blood parasites in vectors reveal a united blackfly community in the upper canopy.

Parasites & vectors, 13(1):309.

BACKGROUND: The behaviour of blood-sucking arthropods is a crucial determinant of blood protozoan distribution and hence of host-parasite coevolution, but it is very challenging to study in the wild. The molecular identification of parasite lineages in vectors can be a useful key to understand the behaviour and transmission patterns realised by these vectors.

METHODS: In this study, we collected blackflies around nests of three raptor species in the upper forest canopy in central Europe and examined the presence of vertebrate DNA and haemosporidian parasites in them. We molecularly analysed 156 blackfly individuals, their vertebrate blood meals, and the haemosporidian parasite lineages they carried.

RESULTS: We identified nine species of Simulium blackflies, largely belonging to the subgenera Nevermannia and Eusimulium. Only 1% of the collected specimens was visibly engorged, and only 4% contained remains of host DNA. However, in 29% of the blackflies Leucocytozoon lineages were identified, which is evidence of a previous blood meal on an avian host. Based on the known vertebrate hosts of the recorded Leucocytozoon lineages, we can infer that large and/or abundant birds, such as thrushes, crows, pigeons, birds of prey, owls and tits are the main targets of ornithophilic blackflies in the canopy. Blackfly species contained similar proportions of host group-specific parasite lineages and thus do not appear to be associated with particular host groups.

CONCLUSIONS: The Leucocytozoon clade infecting thrushes, crows, and pigeons present in most represented blackfly species suggests a lack of association between hosts and blackflies, which can increase the probability of host switches of blood parasites. However, the composition of the simuliid species differed between nests of common buzzards, goshawks and red kites. This segregation can be explained by coinciding habitat preferences between host and vector, and may lead to the fast speciation of Leucocytozoon parasites. Thus, subtle ecological preferences and lack of host preference of vectors in the canopy may enable both parasite diversification and host switches, and enforce a habitat-dependent evolution of avian malaria parasites and related haemosporidia.

RevDate: 2020-12-14
CmpDate: 2020-12-08

Wang L, Luo Y, Wang H, et al (2020)

Azure-winged magpies fail to understand the principle of mirror imaging.

Behavioural processes, 177:104155.

Mirror self-recognition (MSR) is considered a crucial step in the emergence of self-cognition. The MSR paradigm has become a standard method for evaluating self-cognition in several species. For example, Eurasian magpies and Indian house crows have passed the mark test for self-cognition, whereas efforts to find MSR in other corvid species have failed. However, no literature has conducted MSR tests on azure-winged magpies, a species of corvids. Therefore, the current research aimed to investigate the MSR behaviours of azure-winged magpies upon looking into a mirror for the first time. The study included four tests: (1) mirror preference and standardised mirror exploration, (2) single vertical mirror test, (3) mark test and (4) mirror-triggered search test. The azure-winged magpies displayed immense curiosity towards the mirror and their images in the mirror in Test 1&2. In the subsequent mark tests, they failed to recognise themselves in the mirror and regarded their images as conspecifics. Behaviour analysis showed no significant difference between marked and unmarked behaviours. Finally they seemed to infer the presence of bait from the image in the mirror, but were found to fail to understand that the location of the bait in the mirror was the same as that in the real world. For a better insight into the MSR behaviour of azure-winged magpies, research studies involving prolonged mirror exposure and training are recommended.

RevDate: 2021-03-23
CmpDate: 2021-03-23

Uomini N, Fairlie J, Gray RD, et al (2020)

Extended parenting and the evolution of cognition.

Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 375(1803):20190495.

Traditional attempts to understand the evolution of human cognition compare humans with other primates. This research showed that relative brain size covaries with cognitive skills, while adaptations that buffer the developmental and energetic costs of large brains (e.g. allomaternal care), and ecological or social benefits of cognitive abilities, are critical for their evolution. To understand the drivers of cognitive adaptations, it is profitable to consider distant lineages with convergently evolved cognitions. Here, we examine the facilitators of cognitive evolution in corvid birds, where some species display cultural learning, with an emphasis on family life. We propose that extended parenting (protracted parent-offspring association) is pivotal in the evolution of cognition: it combines critical life-history, social and ecological conditions allowing for the development and maintenance of cognitive skillsets that confer fitness benefits to individuals. This novel hypothesis complements the extended childhood idea by considering the parents' role in juvenile development. Using phylogenetic comparative analyses, we show that corvids have larger body sizes, longer development times, extended parenting and larger relative brain sizes than other passerines. Case studies from two corvid species with different ecologies and social systems highlight the critical role of life-history features on juveniles' cognitive development: extended parenting provides a safe haven, access to tolerant role models, reliable learning opportunities and food, resulting in higher survival. The benefits of extended juvenile learning periods, over evolutionary time, lead to selection for expanded cognitive skillsets. Similarly, in our ancestors, cooperative breeding and increased group sizes facilitated learning and teaching. Our analyses highlight the critical role of life-history, ecological and social factors that underlie both extended parenting and expanded cognitive skillsets. This article is part of the theme issue 'Life history and learning: how childhood, caregiving and old age shape cognition and culture in humans and other animals'.

RevDate: 2020-05-28

Brecht KF, Müller J, A Nieder (2020)

Carrion crows (Corvus corone corone) fail the mirror mark test yet again.

Journal of comparative psychology (Washington, D.C. : 1983) pii:2020-37266-001 [Epub ahead of print].

The mirror mark test is generally considered to be an indicator of an animal's ability to recognize itself in the mirror. For this test, an animal is confronted with a mirror and has a mark placed where it can see the mark only with the help of the mirror. When the animal extensively touches or interacts with the mark, compared with control conditions, the mirror mark test is passed. Many nonhuman animal species have been tested, but few have succeeded. After magpies and Indian house crows passed, there has been a sustained interest to find out whether other corvids would pass the mirror mark test. Here, we presented 12 carrion crows (Corvus corone corone) with the mirror mark test. There was no significant increase of mark-directed behavior in the mirror mark test, compared with control conditions. We find very few occasions of mark-directed behaviors and have to interpret them in the context of self-directed behavior more generally. In addition, we show that our crows were motivated to interact with a mark when it was visible to them without the aid of a mirror. We conclude that our crows fail the test, and thereby replicate previous studies showing a similar failure in corvids, and crows in particular. Because our study adds to the growing literature of corvids failing the mirror mark test, the issue of mirror self-recognition in these birds remains controversial. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

RevDate: 2020-08-12
CmpDate: 2020-08-12

Clarke MJ, Fraser EE, IG Warkentin (2020)

Fine spatial-scale variation in scavenger activity influences avian mortality assessments on a boreal island.

PloS one, 15(5):e0233427.

Bird-window collisions are the second leading cause of human-related avian mortality for songbirds in Canada. Our ability to accurately estimate the number of fatalities caused by window collisions is affected by several biases, including the removal of carcasses by scavengers prior to those carcasses being detected during surveys. We investigated the role of scavenger behavior in modifying perceived carcass removal rate while describing habitat-specific differences for the scavengers present in a relatively scavenger-depauperate island ecosystem. We used motion activated cameras to monitor the fate of hatchling chicken carcasses placed at building (under both windows and windowless walls) and forest (open and closed canopy) sites in western Newfoundland, Canada. We recorded the identity of scavengers, timing of events, and frequency of repeat scavenging at sites. Using 2 treatments, we also assessed how scavenging varied with 2 levels of carcass availability (daily versus every third day). Scavenger activities differed substantially between forest and building sites. Only common ravens (Corvus corax) removed carcasses at building sites, with 25 of 26 removals occurring under windows. Burying beetles (Nicrophorus spp.) dominated scavenging at forest sites (14 of 18 removals), completely removing carcasses from sight in under 24 hours. Availability had no effect on removal rate. These findings suggest that ravens look for carcasses near building windows, where bird-window collision fatalities create predictable food sources, but that this learning preceded the study. Such behavior resulted in highly heterogeneous scavenging rates at fine spatial scales indicating the need for careful consideration of carcass and camera placement when monitoring scavenger activity. Our observations of burying beetle activity indicate that future studies investigating bird collision mortality near forested habitats and with infrequent surveys, should consider local invertebrate community composition during survey design. The high incidence of invertebrate scavenging may compensate for the reduced vertebrate scavenger community of insular Newfoundland.

RevDate: 2020-05-14

Soler M, Colmenero JM, Pérez-Contreras T, et al (2020)

Replication of the mirror mark test experiment in the magpie (Pica pica) does not provide evidence of self-recognition.

Journal of comparative psychology (Washington, D.C. : 1983) pii:2020-31404-001 [Epub ahead of print].

Self-recognition in animals is demonstrated when individuals pass the mark test. Formerly, it was thought that self-recognition was restricted to humans, great apes, and certain mammals with large brains and highly evolved social cognition. However, 1 study showed that 2 out of 5 magpies (Pica pica) passed the mark test, suggesting that magpies have a similar level of cognitive abilities to great apes. The scientific advancement depends on confidence in published science, and this confidence can be reached only after rigorous replication of published studies. Here, we present a close replication of the magpie study but using a larger sample size while following a very similar experimental protocol. Like the previous study, in our experiment, magpies showed both social and self-directed behavior more frequently in front of the mirror versus a control cardboard stimulus. However, during the mark test, self-directed behavior proved more frequent in front of the cardboard than in the mirror. Thus, our replication failed to confirm the previous results. Close replications, while not disproving an earlier study, identify results that should be considered with caution. Therefore, more replication studies and additional experimental work is needed to unambiguously demonstrate that magpies are consistently able to pass the mark test. The existence of compelling evidence of self-recognition in other corvid species is discussed in depth. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

RevDate: 2020-09-28

Gill LF, van Schaik J, von Bayern AMP, et al (2020)

Genetic monogamy despite frequent extrapair copulations in "strictly monogamous" wild jackdaws.

Behavioral ecology : official journal of the International Society for Behavioral Ecology, 31(1):247-260.

"Monogamy" refers to different components of pair exclusiveness: the social pair, sexual partners, and the genetic outcome of sexual encounters. Avian monogamy is usually defined socially or genetically, whereas quantifications of sexual behavior remain scarce. Jackdaws (Corvus monedula) are considered a rare example of strict monogamy in songbirds, with lifelong pair bonds and little genetic evidence for extrapair (EP) offspring. Yet jackdaw copulations, although accompanied by loud copulation calls, are rarely observed because they occur visually concealed inside nest cavities. Using full-day nest-box video surveillance and on-bird acoustic bio-logging, we directly observed jackdaw sexual behavior and compared it to the corresponding genetic outcome obtained via molecular parentage analysis. In the video-observed nests, we found genetic monogamy but frequently detected forced EP sexual behavior, accompanied by characteristic male copulation calls. We, thus, challenge the long-held notion of strict jackdaw monogamy at the sexual level. Our data suggest that male mate guarding and frequent intrapair copulations during the female fertile phase, as well as the forced nature of the copulations, could explain the absence of EP offspring. Because EP copulation behavior appeared to be costly for both sexes, we suggest that immediate fitness benefits are an unlikely explanation for its prevalence. Instead, sexual conflict and dominance effects could interact to shape the spatiotemporal pattern of EP sexual behavior in this species. Our results call for larger-scale investigations of jackdaw sexual behavior and parentage and highlight the importance of combining social, sexual, and genetic data sets for a more complete understanding of mating systems.

RevDate: 2020-10-23
CmpDate: 2020-10-23

Martínez JG, Molina-Morales M, Precioso M, et al (2020)

Age-Related Brood Parasitism and Egg Rejection in Magpie Hosts.

The American naturalist, 195(5):876-885.

When the strength or nature of a host-parasite interaction changes over the host life cycle, the consequences of parasitism can depend on host population age structure. Avian brood parasites reduce hosts' breeding success, and host age may play a role in this interaction if younger hosts are more likely parasitized and/or less able to defend themselves. We analyzed whether the age of female magpie (Pica pica) hosts is associated with parasite attack or their ability to reject foreign eggs. We recorded parasitism and model egg rejection of known-age individuals over their lifetime and established whether the likelihood of parasitism or egg rejection changed with age or longevity. Parasitism probability did not change with female age, and there was a trend toward longer-lived females being less likely to be parasitized. However, model egg rejection probability increased with age for each individual female, and longer-lived females were more prone to reject model eggs. Most females in the population were young, and the majority of them accepted model eggs, suggesting that brood parasites exploiting younger host individuals are benefitting from a lower defense level of their hosts. Our results stress that the intensity of selection by brood parasites may be mediated by the age structure of host populations, a to-date neglected aspect in brood parasite-host research.

RevDate: 2020-07-02
CmpDate: 2020-07-01

Lambert ML, M Osvath (2020)

Investigating information seeking in ravens (Corvus corax).

Animal cognition, 23(4):671-680.

Measuring the responses of non-human animals to situations of uncertainty is thought to shed light on an animal's metacognitive processes; namely, whether they monitor their own knowledge states. For example, when presented with a foraging task, great apes and macaques selectively seek information about the location of a food item when they have not seen where it was hidden, compared to when they have. We presented this same information seeking task to ravens, in which a food item was hidden in one of three containers, and subjects could either watch where the food was hidden, infer its location through visual or auditory clues, or were given no information. We found that unlike several ape species and macaques, but similar to capuchin monkeys, the ravens looked inside at least one tube on every trial, but typically only once, inside the baited tube, when they had either witnessed it being baited or could visually infer the reward's location. In contrast, subjects looked more often within trials in which they had not witnessed the baiting or were provided with auditory cues about the reward's location. Several potential explanations for these ceiling levels of looking are discussed, including how it may relate to the uncertainty faced by ravens when retrieving food caches.

RevDate: 2021-04-01

Gallego-Abenza M, Loretto MC, T Bugnyar (2020)

Decision time modulates social foraging success in wild common ravens, Corvus corax.

Ethology : formerly Zeitschrift fur Tierpsychologie, 126(4):413-422.

Social foraging provides several benefits for individuals but also bears the potential costs of higher competition. In some species, such competition arises through kleptoparasitism, that is when an animal takes food which was caught or collected by a member of its social group. Except in the context of caching, few studies have investigated how individuals avoid kleptoparasitism, which could be based on physical strength/dominance but also cognitive skills. Here, we investigated the foraging success of wild common ravens, Corvus corax, experiencing high levels of kleptoparasitism from conspecifics when snatching food from the daily feedings of captive wild boars in a game park in the Austrian Alps. Success in keeping the food depended mainly on the individuals' age class and was positively correlated with the time to make a decision in whether to fly off with food or consume it on site. While the effect of age class suggests that dominant and/or experienced individuals are better in avoiding kleptoparasitism, the effect of decision time indicates that individuals benefit from applying cognition to such decision-making, independently of age class. We discuss our findings in the context of the ecological and social intelligence hypotheses referring to the development of cognitive abilities. We conclude that investigating which factors underline kleptoparasitism avoidance is a promising scenario to test specific predictions derived from these hypotheses.

RevDate: 2020-10-16
CmpDate: 2020-10-16

England ME, Pearce-Kelly P, Brugman VA, et al (2020)

Culicoides species composition and molecular identification of host blood meals at two zoos in the UK.

Parasites & vectors, 13(1):139.

BACKGROUND: Culicoides biting midges are biological vectors of arboviruses including bluetongue virus (BTV), Schmallenberg virus (SBV) and African horse sickness virus (AHSV). Zoos are home to a wide range of 'at risk' exotic and native species of animals. These animals have a high value both in monetary terms, conservation significance and breeding potential. To understand the risk these viruses pose to zoo animals, it is necessary to characterise the Culicoides fauna at zoos and determine which potential vector species are feeding on which hosts.

METHODS: Light-suction traps were used at two UK zoos: the Zoological Society of London (ZSL) London Zoo (LZ) and ZSL Whipsnade Zoo (WZ). Traps were run one night each week from June 2014 to June 2015. Culicoides were morphologically identified to the species level and any blood-fed Culicoides were processed for blood-meal analysis. DNA from blood meals was extracted and amplified using previously published primers. Sequencing was then carried out to determine the host species.

RESULTS: A total of 11,648 Culicoides were trapped and identified (n = 5880 from ZSL WZ; n = 5768 from ZSL LZ), constituting 25 different species. The six putative vectors of BTV, SBV and AHSV in northern Europe were found at both zoos and made up the majority of the total catch (n = 10,701). A total of 31 host sequences were obtained from blood-fed Culicoides. Culicoides obsoletus/C. scoticus, Culicoides dewulfi, Culicoides parroti and Culicoides punctatus were found to be biting a wide range of mammals including Bactrian camels, Indian rhinoceros, Asian elephants and humans, with Culicoides obsoletus/C. scoticus also biting Darwin's rhea. The bird-biting species, Culicoides achrayi, was found to be feeding on blackbirds, blue tits, magpies and carrion crows.

CONCLUSIONS: To our knowledge, this is the first study to directly confirm blood-feeding of Culicoides on exotic zoo animals in the UK and shows that they are able to utilise a wide range of exotic as well as native host species. Due to the susceptibility of some zoo animals to Culicoides-borne arboviruses, this study demonstrates that in the event of an outbreak of one of these viruses in the UK, preventative and mitigating measures would need to be taken.

RevDate: 2020-05-18
CmpDate: 2020-05-12

Miller R, Gruber R, Frohnwieser A, et al (2020)

Decision-making flexibility in New Caledonian crows, young children and adult humans in a multi-dimensional tool-use task.

PloS one, 15(3):e0219874.

The ability to make profitable decisions in natural foraging contexts may be influenced by an additional requirement of tool-use, due to increased levels of relational complexity and additional work-effort imposed by tool-use, compared with simply choosing between an immediate and delayed food item. We examined the flexibility for making the most profitable decisions in a multi-dimensional tool-use task, involving different apparatuses, tools and rewards of varying quality, in 3-5-year-old children, adult humans and tool-making New Caledonian crows (Corvus moneduloides). We also compared our results to previous studies on habitually tool-making orangutans (Pongo abelii) and non-tool-making Goffin's cockatoos (Cacatua goffiniana). Adult humans, cockatoos and crows, but not children and orangutans, did not select a tool when it was not necessary, which was the more profitable choice in this situation. Adult humans, orangutans and cockatoos, but not crows and children, were able to refrain from selecting non-functional tools. By contrast, the birds, but not the primates tested, struggled to attend to multiple variables-where two apparatuses, two tools and two reward qualities were presented simultaneously-without extended experience. These findings indicate: (1) in a similar manner to humans and orangutans, New Caledonian crows and Goffin's cockatoos can flexibly make profitable decisions in some decision-making tool-use tasks, though the birds may struggle when tasks become more complex; (2) children and orangutans may have a bias to use tools in situations where adults and other tool-making species do not.

RevDate: 2020-09-28

Tringali A, Sherer DL, Cosgrove J, et al (2020)

Life history stage explains behavior in a social network before and during the early breeding season in a cooperatively breeding bird.

PeerJ, 8:e8302.

In species with stage-structured populations selection pressures may vary between different life history stages and result in stage-specific behaviors. We use life history stage to explain variation in the pre and early breeding season social behavior of a cooperatively breeding bird, the Florida scrub-jay (Aphelocoma coerulescens) using social network analysis. Life history stage explains much of the variation we observed in social network position. These differences are consistent with nearly 50 years of natural history observations and generally conform to a priori predictions about how individuals in different stages should behave to maximize their individual fitness. Where the results from the social network analysis differ from the a priori predictions suggest that social interactions between members of different groups are more important for breeders than previously thought. Our results emphasize the importance of accounting for life history stage in studies of individual social behavior.

RevDate: 2021-02-23
CmpDate: 2020-12-04

Fongaro E, J Rose (2020)

Crows control working memory before and after stimulus encoding.

Scientific reports, 10(1):3253.

The capacity of working memory is limited and this limit is comparable in crows and primates. To maximize this resource, humans use attention to select only relevant information for maintenance. Interestingly, attention-cues are effective not only before but also after the presentation of to-be-remembered stimuli, highlighting control mechanisms beyond sensory selection. Here we explore if crows are also capable of these forms of control over working memory. Two crows (Corvus corone) were trained to memorize two, four or six visual stimuli. Comparable to our previous results, the crows showed a decrease in performance with increasing working memory load. Using attention cues, we indicated the critical stimulus on a given trial. These cues were either presented before (pre-cue) or after sample-presentation (retro-cue). On other trials no cue was given as to which stimulus was critical. We found that both pre- and retro-cues enhance the performance of the birds. These results show that crows, like humans, can utilize attention to select relevant stimuli for maintenance in working memory. Importantly, crows can also utilize cues to make the most of their working memory capacity even after the stimuli are already held in working memory. This strongly implies that crows can engage in efficient control over working memory.

RevDate: 2021-07-02
CmpDate: 2021-07-02

Knief U, Bossu CM, JBW Wolf (2020)

Extra-pair paternity as a strategy to reduce the costs of heterospecific reproduction? Insights from the crow hybrid zone.

Journal of evolutionary biology, 33(5):727-733.

Within hybrid zones of socially monogamous species, the number of mating opportunities with a conspecific can be limited. As a consequence, individuals may mate with a heterospecific (social) partner despite possible fitness costs to their hybrid offspring. Extra-pair copulations with a conspecific may thus arise as a possible post hoc strategy to reduce the costs of hybridization. We here assessed the rate of extra-pair paternity in the hybrid zone between all-black carrion crows (Corvus (corone) corone) and grey hooded crows (C. (c.) cornix) and tested whether extra-pair paternity (EPP) was more likely in broods where parents differed in plumage colour. The proportion of broods with at least one extra-pair offspring and the proportion of extra-pair offspring were low overall (6.98% and 2.90%, respectively) with no evidence of hybrid broods having higher EPP rates than purebred nests.

RevDate: 2020-09-28

Tryjanowski P, Hetman M, Czechowski P, et al (2020)

Birds Drinking Alcohol: Species and Relationship with People. A Review of Information from Scientific Literature and Social Media.

Animals : an open access journal from MDPI, 10(2):.

Ethanol is a natural by-product of the fermentation process of fruit sugars and is occasionally consumed by fruit-eating and tree sap drinking birds. Information on this form of alcohol consumption features in the scientific literature. However, as pets or as wild animals living close to humans in urban habitats, birds have increasing possibilities to consume alcohol from beverages, such as beer, wine or spirits. Some observations have been discussed in a light-hearted manner in mass media and social media, but without any generalization of why some bird species drink the beverages intentionally or unintentionally provided by humans. To check which species and in what circumstances birds drink alcohol and how this is evaluated by humans, we reviewed the scientific literature and analysed videos from YouTube. In total we found and analysed 8 scientific papers and 179 YouTube videos, from which we identified at least 55 species (in some cases not all birds were identified to species level), 11 in the scientific literature and 47 in videos. The distribution of these species over the avian phylogenetic tree suggests that the origin of this convergent behaviour is mainly by human influence. The two data sources differed in the species covered. Videos typically presented interactions of birds with human-provided alcoholic beverages, and were dominated by two groups of intelligent birds: parrots and corvids. The popularity of YouTube videos for a particular species was positively correlated with the general popularity of the species as measured by the number of hits (results listed) on Google. Human responses to the videos were generally very positive and we analysed how the responses were influenced by factors derived from viewing the videos. Moreover, YouTube videos also provide information on at least 47 new bird species not previously mentioned as using alcohol, and our results suggest that parrots in particular can be potentially good candidates for future restricted laboratory studies on the effect of ethanol on birds and their relationship with humans.

RevDate: 2021-05-17
CmpDate: 2021-05-17

Swift KN, Marzluff JM, Templeton CN, et al (2020)

Brain activity underlying American crow processing of encounters with dead conspecifics.

Behavioural brain research, 385:112546.

Animals utilize a variety of auditory and visual cues to navigate the landscape of fear. For some species, including corvids, dead conspecifics appear to act as one such visual cue of danger, and prompt alarm calling by attending conspecifics. Which brain regions mediate responses to dead conspecifics, and how this compares to other threats, has so far only been speculative. Using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) we contrast the metabolic response to visual and auditory cues associated with a dead conspecific among five a priori selected regions in the American crow (Corvus brachyrhynchos) brain: the hippocampus, nidopallium caudolaterale, striatum, amygdala, and the septum. Using a repeated-measures, fully balanced approach, we exposed crows to four stimuli: a dead conspecific, a dead song sparrow (Melospiza melodia), conspecific alarm calls given in response to a dead crow, and conspecific food begging calls. We find that in response to observations of a dead crow, crows show significant activity in areas associated with higher-order decision-making (NCL), but not in areas associated with social behaviors or fear learning. We do not find strong differences in activation between hearing alarm calls and food begging calls; both activate the NCL. Lastly, repeated exposures to negative stimuli had a marginal effect on later increasing the subjects' brain activity in response to control stimuli, suggesting that crows might quickly learn from negative experiences.

RevDate: 2021-02-04
CmpDate: 2020-11-20

Segura A, Jimenez J, P Acevedo (2020)

Predation of young tortoises by ravens: the effect of habitat structure on tortoise detectability and abundance.

Scientific reports, 10(1):1874.

The predation of young tortoise is considered a major cause of mortality for many tortoise species. The predation by common ravens has been identified as being responsible for significant decreases in tortoise populations. Mediterranean spur-thighed tortoise hatchlings and juveniles in Maamora forest (Morocco) were studied in order to describe the size/age class predation of common ravens on young tortoises and infer the drivers of predation risk and population abundance. The results showed a high level of predation on young tortoises (<75 mm carapace length) attributed to ravens in areas with low vegetation cover, representing 100% of the cases of mortality (n = 147), but it was moderate in covered areas (n = 19), representing 12-27%. The population structure of living juveniles differed significantly between covered and uncovered areas, thus suggesting that raven predation might modify juvenile population structure. Finally, N-mixture models showed a positive relationship between (i) bare cover and tortoise detectability that is only evidenced when the plot is far from a perch and (ii) population abundance and shrub species-richness, being higher in uncovered areas. Our results improve the knowledge on predation and survival on this critical stage in life, which is crucial for the conservation of the Mediterranean spur-thighed tortoise.

RevDate: 2020-07-16
CmpDate: 2020-07-16

Dutour M, AR Ridley (2020)

Females sing more often and at higher frequencies than males in Australian magpies.

Behavioural processes, 172:104045.

Birdsong is a particularly useful model for animal communication studies. However, current knowledge is derived mainly from the study of male song, and is therefore incomplete. Here, we investigated whether singing behaviour differs between sexes in the cooperatively breeding Western Australian magpie (Gymnorhina tibicen dorsalis). This subspecies lives in territorial groups, and in our population there is a female-biased sex ratio, which may lead to a high level of female-female competition for males. Observations of 94 magpies (54 females, 40 males) revealed that females sang more often than males. As bird song is a sexually multidimensional signal, we also studied amplitude and structure of the main territorial high-amplitude song in magpie; the carol. We found that females sing at the same amplitude as males, but that male and female carols exhibit differences in frequency. These results highlight the importance of studying female song and may change our perception regarding the evolution of sex-specific traits, given the primary focus on male singing as a sexually selected trait in the literature to date. The next step is to discover additional species in which females sing more than males in order to improve our currently incomplete understanding of the evolution of bird song.

RevDate: 2021-01-14
CmpDate: 2020-11-17

Vernouillet A, DM Kelly (2020)

Individual exploratory responses are not repeatable across time or context for four species of food-storing corvid.

Scientific reports, 10(1):394.

Exploration is among one of the most studied of animal personality traits (i.e., individual-level behavioural responses repeatable across time and contexts). However, not all species show clear evidence of this personality trait, and this is particularly so for members of the Corvidae family. We assessed the exploratory behaviour of four food-caching corvid species: pinyon jays (Gymnorhinus cyanocephalus), Clark's nutcrackers (Nucifraga columbiana), California scrub jays (Aphelocoma californica), and black-billed magpies (Pica hudsonia). Contextual repeatability was assessed through examining behavioural measures during the Novel Environment task and the Novel Object task, whereas temporal repeatability was assessed by examining changes in these measures over repeated trials. Our results suggest that, for corvids, an individual's exploratory behaviour was not repeatable across contexts or over time. Hence, we found no evidence that exploration constitutes a personality trait for these species of corvid. We did find differences in exploratory behaviour, at a species level, that may be explained by relative reliance on cached food.

RevDate: 2020-10-01

Kövér L, Lengyel S, Takenaka M, et al (2019)

Why do zoos attract crows? A comparative study from Europe and Asia.

Ecology and evolution, 9(24):14465-14475.

Crows have successfully colonized many cities, and urban zoos have been important in this process. To evaluate why zoos attract crows, we quantified crow numbers and behavior in three zoos in Europe (Debrecen, Edinburgh, Vienna) and one in Asia (Sapporo). Data were collected in 445 surveys over 297 days in summer 2014 and winter 2014-2015. We found that crow numbers were highest in Vienna, intermediate in Debrecen and Edinburgh and lowest in Sapporo, increased significantly from summer to winter (Debrecen, Edinburgh, Vienna), and from mornings to afternoons (Debrecen, Sapporo, Vienna), and were higher in sunny weather than in cloudy weather with precipitation and when visitor numbers were low (Debrecen, Vienna). The crows' use of natural food was highest in Vienna, intermediate in Edinburgh and Sapporo, and low in Debrecen. The use of anthropogenic food was high in Debrecen and Sapporo, where the availability of open grassy areas typically used by crows for natural foraging was low. In Sapporo, food availability was more limited than in other zoos, resulting in strong territoriality and few crows in summer, which decreased further in winter. Our study indicates that crows are primarily attracted to zoos by food availability and secondarily by breeding opportunities and that the relative importance of natural versus anthropogenic food sources may vary with zoo habitat structure. Our study draws attention to a previously overlooked role of zoos in urban biodiversity conservation. It may also provide useful information for the management of crow populations, if necessary, and for the planning of urban areas.

RevDate: 2020-10-01

Jiang S, Li Z, Cheng X, et al (2020)

The first pterosaur basihyal, shedding light on the evolution and function of pterosaur hyoid apparatuses.

PeerJ, 8:e8292.

The pterosaur is the first known vertebrate clade to achieve powered flight. Its hyoid apparatus shows a simplification similar to that of birds, although samples of the apparatus are rare, limiting the ability to make an accurate determination. In this study we reveal a new pterosaur specimen, including the first definite basihyal. Through the comparison of pterosaur hyoids, a trend has been discovered for the shortened hyoid relative to the length of the skull, indicating a diminished role of lingual retraction during the evolution of the pterosaur. The new material, possibly from a gallodactylid Gladocephaloideus, represents one of the least effective lingual retractions in all pterosaurs. Based on the structure of an elongated ceratobranchial and retroarticular process on mandibles, the function of the Y-shaped istiodactylid tongue bone is similar to those of scavenger crows rather than chameleons, which is consistent with the interpretation of the scavenging behavior of this taxon. More fossil samples are needed for further study on the function of other pterosaur hyoids.

RevDate: 2020-11-03
CmpDate: 2020-11-03

Spanoudis CG, Andreadis SS, Bray DP, et al (2020)

Behavioural response of the house mosquitoes Culex quinquefasciatus and Culex pipiens molestus to avian odours and its reliance on carbon dioxide.

Medical and veterinary entomology, 34(2):129-137.

How Culex (Diptera: Culicidae) mosquitoes select and discriminate between potential avian hosts is critical for understanding the epidemiology of West Nile virus. Therefore, the present authors studied the behavioural responses of Culex quinquefasciatus (Say) and Culex pipiens molestus (Forsskål) to headspace volatiles of three avian species [chicken and pigeon (sexes analysed separately), and magpie], presented either alone or in combination with 600 p.p.m. carbon dioxide (CO2). The attraction of Cx. quinquefasciatus to the headspace volatiles of both sexes of chicken, and of female pigeon, in combination with CO2 was significantly higher than that achieved by the CO2 and solvent control. Although Cx. p. molestus was attracted to headspace volatiles of chickens and magpies, it was repelled by those of female pigeons when combined with CO2 . An increased effect between the avian volatiles and CO2 was observed for Cx. quinquefasciatus, whereas the addition of CO2 had no effect on the attraction of Cx. p. molestus females. The results of this study demonstrate that Cx. quinquefasciatus and Cx. p. molestus are attracted to the odour of potential avian hosts. Future studies aimed at identifying the bioactive volatile compounds in the headspace of chickens may contribute to the potential development of effective surveillance and control tools against Culex species.

RevDate: 2020-06-10
CmpDate: 2020-06-10

Abadi SH, Wacker DW, Newton JG, et al (2019)

Acoustic localization of crows in pre-roost aggregations.

The Journal of the Acoustical Society of America, 146(6):4664.

Crows are highly intelligent and social creatures. Each night during the non-breeding period, they gather on large pre-roost aggregations as they move towards their communal roost where they sleep. Crows make numerous and varied vocalizations on these pre-roost aggregations, but the purpose of these calls, and vocal communication in general, in these pre-roost aggregations is not fully understood. In this paper, an array of four microphones is used as a non-intrusive means to observe crow vocal behavior in pre-roost aggregations in the absence of human observers. By passively localizing animal vocalizations, the location of individuals can be monitored while simultaneously recording the acoustic structure and organization of their calls. Simulations and experiment are undertaken to study the performance of two time difference of arrival-based methods (hyperbolic location estimator and maximum likelihood estimator) for call localization. The effect of signal-to-noise ratio and uncertainty in measurement on the localization error is presented. By describing, modeling, and testing these techniques in this innovative context, the authors hope that researchers will employ the authors' approaches in future empirical studies to more fully understand crow vocal behavior.

RevDate: 2020-01-08

Ashton BJ, Thornton A, AR Ridley (2019)

Larger group sizes facilitate the emergence and spread of innovations in a group-living bird.

Animal behaviour, 158:1-7.

The benefits of group living have traditionally been attributed to risk dilution or the efficient exploitation of resources; individuals in social groups may therefore benefit from access to valuable information. If sociality facilitates access to information, then individuals in larger groups may be predicted to solve novel problems faster than individuals in smaller groups. Additionally, larger group sizes may facilitate the subsequent spread of innovations within animal groups, as has been proposed for human societies. We presented a novel foraging task (where a food reward could be accessed by pushing a self-shutting sliding door) to 16 groups of wild, cooperatively breeding Australian magpies, Cracticus tibicen dorsalis, ranging in size from two to 11 individuals. We found a nonlinear decline in the time taken for the innovative behaviour to emerge with increasing group size, and social information use facilitated the transmission of novel behaviour, with it spreading more quickly in larger than smaller groups. This study provides important evidence for a nonlinear relationship between group size and the emergence of innovation (and its subsequent transmission) in a wild population of animals. Further work investigating the scope and strength of group size-innovation relationships, and the mechanisms underpinning them, will help us understand the potential advantages of living in larger social groups.

RevDate: 2020-01-08
CmpDate: 2020-01-03

Ben-David A, Shamon H, Izhaki I, et al (2019)

Increased songbird nest depredation due to Aleppo pine (Pinus halepensis) encroachment in Mediterranean shrubland.

BMC ecology, 19(1):52.

BACKGROUND: In recent decades, a decrease of passerine densities was documented in Mediterranean shrublands. At the same time, a widespread encroachment of Aleppo pines (Pinus halepensis) to Mediterranean shrubland occurred. Such changes in vegetation structure may affect passerine predator assemblage and densities, and in turn impact passerine densities. Depredation during the nesting season is an important factor to influence passerine population size. Understanding the effects of changes in vegetation structure (pine encroachment) on passerine nesting success is the main objective of this study. We do so by assessing the effects of Aleppo pine encroachment on Sardinian warbler (Sylvia melanocephala) nest depredation in Mediterranean shrublands. We examined direct and indirect predation pressures through a gradients of pine density, using four methods: (1) placing dummy nests; (2) acoustic monitoring of mobbing events; (3) direct observations on nest predation using cameras; and (4) observation of Eurasian jay (Garrulus glandarius) behaviour as indirect evidence of predation risk.

RESULTS: We found that Aleppo pine encroachment to Mediterranean shrublands increased nest predation by Eurasian jays. Nest predation was highest in mixed shrubland and pines. These areas are suitable for warblers but had high occurrence rate of Eurasian jays.

CONCLUSIONS: Encroaching pines directly increase activity of Eurasian jays in shrubland habitats, which reduced the nesting success of Sardinian warblers. These findings are supported by multiple methodologies, illustrating different predation pressures along a gradient of pine densities in natural shrublands. Management of Aleppo pine seedlings and removal of unwanted trees in natural shrubland might mitigate arrival and expansion of predators and decrease the predation pressure on passerine nests.

RevDate: 2020-05-29
CmpDate: 2020-05-29

Tätte K, Møller AP, R Mänd (2020)

Corvids exhibit dynamic risk assessment during escape.

Behavioural processes, 170:104017.

It is widely accepted that stationary prey are able to carefully assess the risk levels associated with an approaching predator to make informative decisions on when to escape. However, little is known about subsequent decision-making process. We set out to compare whether escape durations of three species of corvids differ depending on how a human observer (in the role of a predator) behaves after the escape has begun. When birds were being followed during escape, escape durations were the longest, escape trajectory was modified the most during escape, and a larger proportion of individuals changed from terrestrial to aerial escape strategy compared to observations where birds were not followed. Mean horizontal escape angle of ca 120° was also a potential indication that monitoring the threat is taken into account when deciding on the escape trajectory. While there were some differences between the behaviour of these three closely related species, the general patterns supported the notion that birds dynamically assess risk during escape to find an optimal balance between getting caught and spending too much time and energy on escaping. Further research using different predator-prey combinations or making comparisons between habitats could help understand the generality of our results.

RevDate: 2020-11-10
CmpDate: 2020-11-10

Jokimäki J, Suhonen J, Benedetti Y, et al (2020)

Land-sharing vs. land-sparing urban development modulate predator-prey interactions in Europe.

Ecological applications : a publication of the Ecological Society of America, 30(3):e02049.

Urban areas are expanding globally as a consequence of human population increases, with overall negative effects on biodiversity. To prevent the further loss of biodiversity, it is urgent to understand the mechanisms behind this loss to develop evidence-based sustainable solutions to preserve biodiversity in urban landscapes. The two extreme urban development types along a continuum, land-sparing (large, continuous green areas and high-density housing) and land-sharing (small, fragmented green areas and low-density housing) have been the recent focus of debates regarding the pattern of urban development. However, in this context, there is no information on the mechanisms behind the observed biodiversity changes. One of the main mechanisms proposed to explain urban biodiversity loss is the alteration of predator-prey interactions. Using ground-nesting birds as a model system and data from nine European cities, we experimentally tested the effects of these two extreme urban development types on artificial ground nest survival and whether nest survival correlates with the local abundance of ground-nesting birds and their nest predators. Nest survival (n = 554) was lower in land-sharing than in land-sparing urban areas. Nest survival decreased with increasing numbers of local predators (cats and corvids) and with nest visibility. Correspondingly, relative abundance of ground-nesting birds was greater in land-sparing than in land-sharing urban areas, though overall bird species richness was unaffected by the pattern of urban development. We provide the first evidence that predator-prey interactions differ between the two extreme urban development types. Changing interactions may explain the higher proportion of ground-nesting birds in land-sparing areas, and suggest a limitation of the land-sharing model. Nest predator control and the provision of more green-covered urban habitats may also improve conservation of sensitive birds in cities. Our findings provide information on how to further expand our cities without severe loss of urban-sensitive species and give support for land-sparing over land-sharing urban development.

RevDate: 2020-09-02
CmpDate: 2020-09-02

Hirschl RB, Newman E, Cooke-Barber J, et al (2020)

APSA 5.0: Saving even more lifetimes the Jay and Margie Grosfeld presidential symposium.

Journal of pediatric surgery, 55(1):2-17.

In light of APSA's 50th Anniversary, the typical Presidential Address was transformed into a "symposium" consisting of talks on the maturation of our organization to APSA 5.0 and the issues and opportunities related to its internal and external environment, especially as they apply to our pediatric surgical patients. Speakers included the President and experts in the fields of diversity, as well as inequity and poverty in the United States.

RevDate: 2020-05-21
CmpDate: 2020-05-21

Klump BC (2019)

Of crows and tools.

Science (New York, N.Y.), 366(6468):965.

RevDate: 2020-11-21
CmpDate: 2020-07-01

Lambert CT, Sewall KB, LM Guillette (2019)

Questioning the developmental effects of group size on cognitive abilities.

Learning & behavior, 47(4):280-283.

Australian magpies living in larger social groups learned quicker and made fewer errors across four cognitive tasks compared with birds living in smaller social groups, and this pattern may be driven by a developmental effect associated with the cognitive demands of living in larger groups. While Smulders (2018, Learning and Behavior, 1-2, doi:10.3758/s13420-018-0335-0) questioned whether this group size-cognitive performance pattern was driven by motivation rather than cognitive abilities, we question whether there is truly evidence of a developmental effect and whether the relationship between group size and cognitive performance can be explained in other ways. We highlight potential alternative explanations for the relationship between group size and cognitive performance and highlight some of the theoretical issues underlying the developmental effects of group size on cognitive abilities.

RevDate: 2021-01-06
CmpDate: 2020-11-23

Nieder A, R Mooney (2020)

The neurobiology of innate, volitional and learned vocalizations in mammals and birds.

Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 375(1789):20190054.

Vocalization is an ancient vertebrate trait essential to many forms of communication, ranging from courtship calls to free verse. Vocalizations may be entirely innate and evoked by sexual cues or emotional state, as with many types of calls made in primates, rodents and birds; volitional, as with innate calls that, following extensive training, can be evoked by arbitrary sensory cues in non-human primates and corvid songbirds; or learned, acoustically flexible and complex, as with human speech and the courtship songs of oscine songbirds. This review compares and contrasts the neural mechanisms underlying innate, volitional and learned vocalizations, with an emphasis on functional studies in primates, rodents and songbirds. This comparison reveals both highly conserved and convergent mechanisms of vocal production in these different groups, despite their often vast phylogenetic separation. This similarity of central mechanisms for different forms of vocal production presents experimentalists with useful avenues for gaining detailed mechanistic insight into how vocalizations are employed for social and sexual signalling, and how they can be modified through experience to yield new vocal repertoires customized to the individual's social group. This article is part of the theme issue 'What can animal communication teach us about human language?'

RevDate: 2021-01-10
CmpDate: 2020-03-10

Ling H, Mclvor GE, Westley J, et al (2019)

Behavioural plasticity and the transition to order in jackdaw flocks.

Nature communications, 10(1):5174.

Collective behaviour is typically thought to arise from individuals following fixed interaction rules. The possibility that interaction rules may change under different circumstances has thus only rarely been investigated. Here we show that local interactions in flocks of wild jackdaws (Corvus monedula) vary drastically in different contexts, leading to distinct group-level properties. Jackdaws interact with a fixed number of neighbours (topological interactions) when traveling to roosts, but coordinate with neighbours based on spatial distance (metric interactions) during collective anti-predator mobbing events. Consequently, mobbing flocks exhibit a dramatic transition from disordered aggregations to ordered motion as group density increases, unlike transit flocks where order is independent of density. The relationship between group density and group order during this transition agrees well with a generic self-propelled particle model. Our results demonstrate plasticity in local interaction rules and have implications for both natural and artificial collective systems.

RevDate: 2021-01-10
CmpDate: 2020-11-06

Krasheninnikova A, Brucks D, Buffenoir N, et al (2019)

Parrots do not show inequity aversion.

Scientific reports, 9(1):16416.

Inequity aversion, the negative reaction to unequal treatment, is considered a mechanism for stabilizing cooperative interactions between non-kin group members. However, this might only be adaptive for species that switch cooperative partners. Utilizing a comparative approach, inequity aversion has been assessed in many mammalian species and recently also in corvids and one parrot species, kea, revealing mixed results. To broaden our knowledge about the phylogenetic distribution of inequity aversion, we tested four parrot species in the token exchange paradigm. We varied the quality of rewards delivered to dyads of birds, as well as the effort required to obtain a reward. Blue-headed macaws and African grey parrots showed no reaction to being rewarded unequally. The bigger macaws were less willing to exchange tokens in the "unequal" condition compared to the "equal high" condition in which both birds obtained high quality rewards, but a closer examination of the results and the findings from the control conditions reveal that inequity aversion does not account for it. None of the species responded to inequity in terms of effort. Parrots may not exhibit inequity aversion due to interdependence on their life-long partner and the high costs associated with finding a new partner.

RevDate: 2019-12-18

Coomes JR, McIvor GE, A Thornton (2019)

Correction to 'Evidence for individual discrimination and numerical assessment in collective antipredator behaviour in wild jackdaws (Corvus monedula)'.

Biology letters, 15(11):20190740.

RevDate: 2021-01-10
CmpDate: 2020-11-03

Holtmann B, Buskas J, Steele M, et al (2019)

Dominance relationships and coalitionary aggression against conspecifics in female carrion crows.

Scientific reports, 9(1):15922.

Cooperation is a prevailing feature of many animal systems. Coalitionary aggression, where a group of individuals engages in coordinated behaviour to the detriment of conspecific targets, is a form of cooperation involving complex social interactions. To date, evidence has been dominated by studies in humans and other primates with a clear bias towards studies of male-male coalitions. We here characterize coalitionary aggression behaviour in a group of female carrion crows consisting of recruitment, coordinated chase, and attack. The individual of highest social rank liaised with the second most dominant individual to engage in coordinated chase and attack of a lower ranked crow on several occasions. Despite active intervention by the third most highly ranked individual opposing the offenders, the attack finally resulted in the death of the victim. All individuals were unrelated, of the same sex, and naïve to the behaviour excluding kinship, reproduction, and social learning as possible drivers. Instead, the coalition may reflect a strategy of the dominant individual to secure long-term social benefits. Overall, the study provides evidence that members of the crow family engage in coordinated alliances directed against conspecifics as a possible means to manipulate their social environment.

RevDate: 2020-10-01
CmpDate: 2020-08-04

Ling H, Mclvor GE, Westley J, et al (2019)

Collective turns in jackdaw flocks: kinematics and information transfer.

Journal of the Royal Society, Interface, 16(159):20190450.

The rapid, cohesive turns of bird flocks are one of the most vivid examples of collective behaviour in nature, and have attracted much research. Three-dimensional imaging techniques now allow us to characterize the kinematics of turning and their group-level consequences in precise detail. We measured the kinematics of flocks of wild jackdaws executing collective turns in two contexts: during transit to roosts and anti-predator mobbing. All flocks reduced their speed during turns, probably because of constraints on individual flight capability. Turn rates increased with the angle of the turn so that the time to complete turns remained constant. We also find that context may alter where turns are initiated in the flocks: for transit flocks in the absence of predators, initiators were located throughout the flocks, but for mobbing flocks with a fixed ground-based predator, they were always located at the front. Moreover, in some transit flocks, initiators were far apart from each other, potentially because of the existence of subgroups and variation in individual interaction ranges. Finally, we find that as the group size increased the information transfer speed initially increased, but rapidly saturated to a constant value. Our results highlight previously unrecognized complexity in turning kinematics and information transfer in social animals.

RevDate: 2020-07-01
CmpDate: 2020-07-01

Miller R, Frohnwieser A, Schiestl M, et al (2020)

Delayed gratification in New Caledonian crows and young children: influence of reward type and visibility.

Animal cognition, 23(1):71-85.

Self-control underlies cognitive abilities such as decision making and future planning. Delay of gratification is a measure of self-control and involves obtaining a more valuable outcome in the future by tolerating a delay or investing a greater effort in the present. Contextual issues, such as reward visibility and type, may influence delayed gratification performance, although there has been limited comparative investigation between humans and other animals, particularly non-primate species. Here, we adapted an automated 'rotating tray' paradigm used previously with capuchin monkeys to test for delay of gratification ability that requires little pre-test training, where the subject must forgo an immediate, less preferred reward for a delayed, more preferred one. We tested New Caledonian crows and 3-5-year-old human children. We manipulated reward types to differ in quality or quantity (Experiments 1 and 2) as well as visibility (Experiment 2). In Experiments 1 and 2, both species performed better when the rewards varied in quality as opposed to quantity, though performed above chance in both conditions. In Experiment 1, both crows and children were able to delay gratification when both rewards were visible. In Experiment 2, 5-year-old children outperformed 3- and 4-year olds, though overall children still performed well, while the crows struggled when reward visibility was manipulated, a result which may relate to difficulties in tracking the experimenters' hands during baiting. We discuss these findings in relation to the role of contextual issues on self-control when making species comparisons and investigating the mechanisms of self-control.

RevDate: 2020-11-19
CmpDate: 2020-11-19

El-Sayed AK, S Hassan (2020)

Gross morphological features of the air sacs of the hooded crow (Corvus cornix).

Anatomia, histologia, embryologia, 49(2):159-166.

Air sacs are considered to be one of the controlling factors of bird behaviour and habits in addition to their roles in ventilation, regulating body temperature, swimming and flight. As a scavenger and an omnivorous flight bird, air sacs of the hooded crow were the focus of this study. Eight healthy, adult hooded crows were used to examine the morphological characteristics of the air sacs, which were examined grossly and with latex and cast preparations. In general, the morphological overview of the hooded crow air sacs is similar to other avian species. We observed nine air sacs; four paired sacs (cervical, cranial thoracic, caudal thoracic and abdominal air sacs) and one unpaired sac; the clavicular air sac. The cervical air sac communicated to the lung through the medioventral bronchus and had three diverticula; intermuscular, subscapular and subcutaneous. The clavicular air sac communicated with lung through the medioventral bronchus and had subscapular, axillary, humeral, subpectoral and sternal diverticula. The cranial and caudal thoracic air sacs were communicated with lung through the lateroventral bronchi and the both sacs did not have any diverticula. The abdominal air sacs were posterior to the caudal thoracic air sacs. The left abdominal sac was the largest air sac. The right and left abdominal sacs gave off branches to diverticula that pneumatized synsacrum. The abdominal air sacs gave off femoral diverticula behind the hip joint as well as perirenal diverticula.

RevDate: 2021-06-03
CmpDate: 2021-06-03

Vanhooland LC, Bugnyar T, JJM Massen (2020)

Crows (Corvus corone ssp.) check contingency in a mirror yet fail the mirror-mark test.

Journal of comparative psychology (Washington, D.C. : 1983), 134(2):158-169.

Mirror reflections can elicit various behavioral responses ranging from social behavior, which suggests that an animal treats its own reflection as a conspecific, to mirror-guided self-directed behaviors, which appears to be an indication for mirror self-recognition (MSR). MSR is scarcely spread in the animal kingdom. Until recently, only great apes, dolphins, and elephants had successfully passed this test. The range of convergence was, however, expanded by an avian species, the Eurasian magpie (Pica pica). Efforts to find MSR in other corvid species have so far failed, and with only a few studies conducted, the cause of these discrepancies is difficult to identify. In the present study, we examined the responses to mirrors and the ability of MSR in hitherto untested species: the carrion and hooded crows (Corvus corone ssp.). These crows showed a pronounced and lasting interest in the mirror; unlike many species, they did not exhibit social behaviors on their first encounters but immediately started investigating the mirror. Some crows showed contingent behaviors in front of the mirror, but none of the crows showed significant mirror-guided self-directed behaviors nor mark-directed behavior during the subsequent mark test. This lack of mark-directed behavior could not be explained by a lack of interest in the mirror nor in the mark. These findings could indicate that crows lack a concept of self, or the need for other means of investigating self-recognition and self-awareness in avian species. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

RevDate: 2021-01-10
CmpDate: 2019-12-12

Coomes JR, McIvor GE, A Thornton (2019)

Evidence for individual discrimination and numerical assessment in collective antipredator behaviour in wild jackdaws (Corvus monedula).

Biology letters, 15(10):20190380.

Collective responses to threats occur throughout the animal kingdom but little is known about the cognitive processes underpinning them. Antipredator mobbing is one such response. Approaching a predator may be highly risky, but the individual risk declines and the likelihood of repelling the predator increases in larger mobbing groups. The ability to appraise the number of conspecifics involved in a mobbing event could therefore facilitate strategic decisions about whether to join. Mobs are commonly initiated by recruitment calls, which may provide valuable information to guide decision-making. We tested whether the number of wild jackdaws responding to recruitment calls was influenced by the number of callers. As predicted, playbacks simulating three or five callers tended to recruit more individuals than playbacks of one caller. Recruitment also substantially increased if recruits themselves produced calls. These results suggest that jackdaws use individual vocal discrimination to assess the number of conspecifics involved in initiating mobbing events, and use this information to guide their responses. Our results show support for the use of numerical assessment in antipredator mobbing responses and highlight the need for a greater understanding of the cognitive processes involved in collective behaviour.

RevDate: 2020-10-01

Forti LR, Haddad CFB, Leite F, et al (2019)

Notes on vocalizations of Brazilian amphibians IV: advertisement calls of 20 Atlantic Forest frog species.

PeerJ, 7:e7612.

Bioacoustics is a powerful tool used for anuran species diagnoses, given that advertisement calls are signals related to specific recognition and mate attraction. Thus, call descriptions can support species taxonomy. In spite of that, call descriptions are lacking for many species, delaying advances in biodiversity research. Here, we describe the advertisement calls of 20 anuran species from the Brazilian Atlantic Forest. We accessed 50 digital recordings deposited in the Fonoteca Neotropical Jacques Vielliard. Acoustic analyses were carried out in the software Raven pro 1.5. We provide a general comparison of call structure among species inside taxonomic groups and genera. The vocalizations described here belong to poorly known species, which are representatives of six families: Brachycephalidae, Bufonidae, Ceratophryidae, Cycloramphidae, Hylidae, and Phyllomedusidae. Despite this, still there are 163 species of anurans from Atlantic Forest with calls not formally described. Our work represents an important step in providing data for a taxonomic perspective and improving the knowledge of the Atlantic Forest anuran diversity.

RevDate: 2020-07-14
CmpDate: 2020-07-14

Blasco R, Rosell J, Sánchez-Marco A, et al (2019)

Feathers and food: Human-bird interactions at Middle Pleistocene Qesem Cave, Israel.

Journal of human evolution, 136:102653.

The presence of fast-moving small game in the Paleolithic archaeological faunal record has long been considered a key variable to assess fundamental aspects of human behavior and subsistence. Birds occupy a prominent place in this debate not only due to their small size and to the difficulties in capturing them (essentially due to their ability to fly and their elusiveness), but also due to their possible role in the symbolic array in regard to non-nutritional elements (feathers, talons, etc.) and as reflectors of complex human-world relationships. In this study, we attempt to contribute to this topic by presenting taphonomical data of bird specimens from Qesem Cave (Israel), dated between 420 and 200 ka. Human-induced damage, including cut marks, peeling and human gnawing, has been identified on wing bones of Cygnus sp., Columba sp., Corvus ruficollis and Sturnus sp. Our evidence suggests that avian exploitation was not limited to food only-either to complement the human diet or as occasional food item-but also presumably for the use of feathers. While the consumption of birds as a dietary source seems to be evident as early as the Early Pleistocene, the non-alimentary use of inedible elements, such as feathers and talons, appears to be a practice from the Middle Paleolithic onwards. We argue that the combined nutritional and symbolic use of birds is one characteristic of the new mode of adaptation practiced already by the late Lower Paleolithic Acheulo-Yabrudian hominins in the Levant starting 400 ka. The Qesem findings point to the possible emergence of new cognitive and behavioral skills, which are followed in later periods in the Old World. Finally, we discuss the possible ontological and cosmological significance of human-bird interactions to illuminate our hypothesis regarding the emergence of a new perception of human relationships with the world as an integral part of the new Acheulo-Yabrudian mode of adaptation.

RevDate: 2020-04-13
CmpDate: 2020-04-13

Shekhawat S, A Saxena (2020)

Development and applications of an intelligent crow search algorithm based on opposition based learning.

ISA transactions, 99:210-230.

Metaheuristics are proven beneficial tools for solving complex, hard optimization problems. Recently, a plethora of work has been reported on bio inspired optimization algorithms. These algorithms are mimicry of behavior of animals, plants and processes into mathematical paradigms. With these developments, a new entrant in this group is Crow Search Algorithm (CSA). CSA is based on the strategic behavior of crows while searching food, thievery and chasing behavior. This algorithm sometimes suffers with local minima stagnation and unbalance exploration and exploitation phases. To overcome this problem, a cosine function is proposed first, to accelerate the exploration and retard the exploitation process with due course of the iterative process. Secondly the opposition based learning concept is incorporated for enhancing the exploration virtue of CSA. The evolved variant with the inculcation of these two concepts is named as Intelligent Crow Search Algorithm (ICSA). The algorithm is benchmarked on two benchmark function sets, one is the set of 23 standard test functions and another is set of latest benchmark function CEC-2017. Further, the applicability of this variant is tested over structural design problem, frequency wave synthesis problem and Model Order Reduction (MOR). Results reveal that ICSA exhibits competitive performance on benchmarks and real applications when compared with some contemporary optimizers.

RevDate: 2020-03-09
CmpDate: 2020-02-27

Brecht KF, Hage SR, Gavrilov N, et al (2019)

Volitional control of vocalizations in corvid songbirds.

PLoS biology, 17(8):e3000375.

Songbirds are renowned for their acoustically elaborate songs. However, it is unclear whether songbirds can cognitively control their vocal output. Here, we show that crows, songbirds of the corvid family, can be trained to exert control over their vocalizations. In a detection task, three male carrion crows rapidly learned to emit vocalizations in response to a visual cue with no inherent meaning (go trials) and to withhold vocalizations in response to another cue (catch trials). Two of these crows were then trained on a go/nogo task, with the cue colors reversed, in addition to being rewarded for withholding vocalizations to yet another cue (nogo trials). Vocalizations in response to the detection of the go cue were temporally precise and highly reliable in all three crows. Crows also quickly learned to withhold vocal output in nogo trials, showing that vocalizations were not produced by an anticipation of a food reward in correct trials. The results demonstrate that corvids can volitionally control the release and onset of their vocalizations, suggesting that songbird vocalizations are under cognitive control and can be decoupled from affective states.

RevDate: 2020-03-18
CmpDate: 2020-03-18

Vonk J (2019)

Emotional contagion or sensitivity to behavior in ravens?.

Proceedings of the National Academy of Sciences of the United States of America, 116(37):18168.

RevDate: 2021-01-10
CmpDate: 2020-11-06

Probst C, Gethmann J, Amler S, et al (2019)

The potential role of scavengers in spreading African swine fever among wild boar.

Scientific reports, 9(1):11450.

Understanding the transmission patterns of African swine fever (ASF) among wild boar (Sus scrofa) is an issue of major interest, especially in the wake of the current ASF epidemic. Given the high stability of ASF-virus, there is concern about scavengers spreading infectious carcass material in the environment. Here, we describe scavenging activities on 32 wild boar carcasses in their natural habitat in Germany. Using digital cameras, we detected 22 vertebrates at the study sites, thereof two mammal and three bird species scavenging. The most frequently detected species was the raccoon dog Nyctereutes procyonoides (44% of all visits). Raccoon dogs, red foxes (Vulpes vulpes), and buzzards (Buteo buteo) scavenged in the warm and the cold season, while ravens (Corvus corax) and white-tailed eagles (Haliaeetus albicilla) scavenged only in the cold season. In summer, however, insects removed most of the carcass biomass. Although most of the material was consumed on the spot, foxes, raccoon dogs and ravens left the study sites in rare cases with a small piece of meat in their mouths or beaks. We conclude that scavengers represent a minor risk factor for spreading ASF, but may contribute to reducing local virus persistence by metabolizing infected carcasses.

RevDate: 2020-08-03
CmpDate: 2020-08-03

McCoy DE, Schiestl M, Neilands P, et al (2019)

New Caledonian Crows Behave Optimistically after Using Tools.

Current biology : CB, 29(16):2737-2742.e3.

Are complex, species-specific behaviors in animals reinforced by material reward alone or do they also induce positive emotions? Many adaptive human behaviors are intrinsically motivated: they not only improve our material outcomes, but improve our affect as well [1-8]. Work to date on animal optimism, as an indicator of positive affect, has generally focused on how animals react to change in their circumstances, such as when their environment is enriched [9-14] or they are manipulated by humans [15-23], rather than whether complex actions improve emotional state. Here, we show that wild New Caledonian crows are optimistic after tool use, a complex, species-specific behavior. We further demonstrate that this finding cannot be explained by the crows needing to put more effort into gaining food. Our findings therefore raise the possibility that intrinsic motivation (enjoyment) may be a fundamental proximate cause in the evolution of tool use and other complex behaviors. VIDEO ABSTRACT.

LOAD NEXT 100 CITATIONS

RJR Experience and Expertise

Researcher

Robbins holds BS, MS, and PhD degrees in the life sciences. He served as a tenured faculty member in the Zoology and Biological Science departments at Michigan State University. He is currently exploring the intersection between genomics, microbial ecology, and biodiversity — an area that promises to transform our understanding of the biosphere.

Educator

Robbins has extensive experience in college-level education: At MSU he taught introductory biology, genetics, and population genetics. At JHU, he was an instructor for a special course on biological database design. At FHCRC, he team-taught a graduate-level course on the history of genetics. At Bellevue College he taught medical informatics.

Administrator

Robbins has been involved in science administration at both the federal and the institutional levels. At NSF he was a program officer for database activities in the life sciences, at DOE he was a program officer for information infrastructure in the human genome project. At the Fred Hutchinson Cancer Research Center, he served as a vice president for fifteen years.

Technologist

Robbins has been involved with information technology since writing his first Fortran program as a college student. At NSF he was the first program officer for database activities in the life sciences. At JHU he held an appointment in the CS department and served as director of the informatics core for the Genome Data Base. At the FHCRC he was VP for Information Technology.

Publisher

While still at Michigan State, Robbins started his first publishing venture, founding a small company that addressed the short-run publishing needs of instructors in very large undergraduate classes. For more than 20 years, Robbins has been operating The Electronic Scholarly Publishing Project, a web site dedicated to the digital publishing of critical works in science, especially classical genetics.

Speaker

Robbins is well-known for his speaking abilities and is often called upon to provide keynote or plenary addresses at international meetings. For example, in July, 2012, he gave a well-received keynote address at the Global Biodiversity Informatics Congress, sponsored by GBIF and held in Copenhagen. The slides from that talk can be seen HERE.

Facilitator

Robbins is a skilled meeting facilitator. He prefers a participatory approach, with part of the meeting involving dynamic breakout groups, created by the participants in real time: (1) individuals propose breakout groups; (2) everyone signs up for one (or more) groups; (3) the groups with the most interested parties then meet, with reports from each group presented and discussed in a subsequent plenary session.

Designer

Robbins has been engaged with photography and design since the 1960s, when he worked for a professional photography laboratory. He now prefers digital photography and tools for their precision and reproducibility. He designed his first web site more than 20 years ago and he personally designed and implemented this web site. He engages in graphic design as a hobby.

Support this website:
Order from Amazon
We will earn a commission.

This is a must read book for anyone with an interest in invasion biology. The full title of the book lays out the author's premise — The New Wild: Why Invasive Species Will Be Nature's Salvation. Not only is species movement not bad for ecosystems, it is the way that ecosystems respond to perturbation — it is the way ecosystems heal. Even if you are one of those who is absolutely convinced that invasive species are actually "a blight, pollution, an epidemic, or a cancer on nature", you should read this book to clarify your own thinking. True scientific understanding never comes from just interacting with those with whom you already agree. R. Robbins

963 Red Tail Lane
Bellingham, WA 98226

206-300-3443

E-mail: RJR8222@gmail.com

Collection of publications by R J Robbins

Reprints and preprints of publications, slide presentations, instructional materials, and data compilations written or prepared by Robert Robbins. Most papers deal with computational biology, genome informatics, using information technology to support biomedical research, and related matters.

Research Gate page for R J Robbins

ResearchGate is a social networking site for scientists and researchers to share papers, ask and answer questions, and find collaborators. According to a study by Nature and an article in Times Higher Education , it is the largest academic social network in terms of active users.

Curriculum Vitae for R J Robbins

short personal version

Curriculum Vitae for R J Robbins

long standard version

RJR Picks from Around the Web (updated 11 MAY 2018 )