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Ambient noise can cause birds to adjust their songs to avoid masking. Most studies investigate responses to a single noise source (e.g., low-frequency traffic noise, or high-frequency insect noise). Here, we investigated the effects of both anthropogenic and insect noise on vocalizations of four common bird species in Hong Kong. Common Tailorbirds (Orthotomus sutorius) and Eurasian Tree Sparrows (Passer montanus) both sang at a higher frequency in urban areas compared to peri-urban areas. Red-whiskered Bulbuls (Pycnonotus jocosus) in urban areas shifted the only first note of their song upwards. Swinhoe’s White-eye (Zosterops simplex) vocalization changes were correlated with noise level, but did not differ between the peri-urban and urban populations. Insect noise caused the Eurasian Tree Sparrow to reduce both maximum, peak frequency, and overall bandwidth of vocalizations. Insect noise also led to a reduction in maximum frequency in Red-whiskered bulbuls. The presence of both urban noise and insect noise affected the sound of the Common Tailorbirds and Eurasian Tree Sparrows; in urban areas, they no longer increased their minimum song frequency when insect sounds were also present. These results highlight the complexity of the soundscape in urban areas. The presence of both high- and low-frequency ambient noise may make it difficult for urban birds to avoid signal masking while still maintaining their fitness in noisy cities., Studies have shown that birds increase their vocalization pitch under low-frequency urban noise and sing at a lower pitch when exposed to high-frequency insect sounds, but what if they occur simultaneously? Using field recordings, we found that some urban birds no longer adjusted their song in response to urban noise when insect noise is also present. This shows that anthropogenic noise is not the only driver of changes in urban bird songs.

Studying and quantifying behaviour is important to understand how animals interact with their environments. However, manually extracting and analysing behavioural data from the large volume of camera footage collected is often time consuming. Deep learning techniques have emerged as useful tools in automating the analysis of certain behaviours under controlled or laboratory conditions, but the complexities of using raw footage from the field has resulted in this technology remaining largely unexplored as a possible data analysis alternative for animals in situ. Here, we use deep learning techniques to automate the analysis of fish grazing behaviour from real-world field imagery. We collected video footage in sea grass meadows in Queensland, Australia, and trained models on a training data set of over 3000 annotations. We used a combination of dense optical flow to assess pixel movement in underwater footage, spatiotemporal filtering to increase accuracy, and deep learning algorithms to classify grazing behaviour of luderick, Girella tricuspidata. When tested on novel videos the model had not seen in training, the model correctly identified nearly all individual grazing events. Deep learning shows promise as a viable tool for determining animal behaviour from underwater videos, and with further development offers an alternative to current time-consuming manual methods of data extraction.

Animals with small nervous systems may be prone to limitations in processing ability when confronted with a diversity of stimuli, especially if these involve multiple sensory modalities. We investigated the effect of the odour of the plant Lantana camara and its dominant volatile compound, β-caryophyllene, on the prey choice decisions of Evarcha culicivora, a jumping spider (Salticidae) that frequently visits L. camara as a site to mate and to obtain nectar. Evarcha culicivora expresses a strong preference for blood-fed female Anopheles mosquitoes as prey. We tested juvenile and adult E. culicivora in experiments involving live prey, lures made from dead prey and virtual prey, when presented with no odour, odour from L. camara and β-caryophyllene. We found that, in the presence of the plant-related odours, E. culicivora's prey preference was no longer expressed. This effect seems to be a consequence of the plant-related odours reducing the extent to which E. culicivora relies on a pre-attack pause and visual fixation routine (‘stationing’) when seeing prey. Stationing may be critical for adequate visual scanning, and thus correct identification of the prey, as we found that the longer the spider was stationed in front of prey before being subjected to a disruption, the more strongly E. culicivora expressed a preference for blood-fed female mosquitoes. This seems to be an unusual example of a specific modulation of visually based prey choice behaviour being mediated by an environmental chemical cue not pertinent to the prey.

The abstract concept of sameness forms the basis of higher-order cognitive operations, including mathematics and language. Historically believed to be unique to humans, evidence of abstract-concept learning in recent decades has been demonstrated in a range of phylogenetically diverse species, indicating that the ability to judge sameness relations is a general process resulting from convergent evolution. However, to date, no research has demonstrated evidence of such learning in any canid species. We trained domestic dogs (n = 6) on a two-choice olfactory matching-to-sample task using a training set of 48 odors in trial-unique sessions. Upon meeting an acquisition criterion (two consecutive sessions ≥ 83% correct), we assessed abstract-concept learning by testing for transfer to novel odors. Dogs matched novel odors with above-chance accuracy and exceeded baseline levels, satisfying previously proposed criteria for full abstract-concept learning. Our findings provide the first evidence of MTS concept learning in dogs, illustrating qualitative similarities with other species. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Major mood syndromes are among the most common and disabling mental disorders. However, a lack of clear delineation of their underlying pathophysiological mechanisms is a major barrier to prevention and optimised treatments. Dysfunction of the 24-h circadian system is a candidate mechanism that has genetic, behavioural, and neurobiological links to mood syndromes. Here, we outline evidence for a new clinical phenotype, which we have called ‘circadian depression’. We propose that key clinical characteristics of circadian depression include disrupted 24-h sleep-wake cycles, reduced motor activity, low subjective energy, and weight gain. The illness course includes early age-of-onset, phenomena suggestive of bipolarity (defined by bidirectional associations between objective motor and subjective energy/mood states), poor response to conventional antidepressant medications, and concurrent cardiometabolic and inflammatory disturbances. Identifying this phenotype could be clinically valuable, as circadian-targeted strategies show promise for reducing depressive symptoms and stabilising illness course. Further investigation of underlying circadian disturbances in mood syndromes is needed to evaluate the clinical utility of this phenotype and guide the optimal use of circadian-targeted interventions.

Sexual conflict over parental investment is widespread among species with biparental care. Studies have indicated that a high degree of behavioural similarity between the two parents can increase offspring survival; however, it remains unclear how sexual conflict over parental care is resolved. In this study, we examined whether similarity of personality traits between the two parents plays an important role in affecting the provisioning behaviour of each sex in a wild population of the chestnut thrush, Turdus rubrocanus. First, as expected, the mating pairs with more similar personality traits had higher provisioning rates than those pairs with dissimilar traits. Moreover, we found that the similarity of personality traits can modulate the sexual conflict over provisioning in this species, as both parents with more similar partners had relatively higher and less divergent provisioning rates. A partner removal experiment revealed how the sole female or male parent responded when the level of conflict over care increased (the removed partner does not provide any care). The majority of males always reduced their provisioning investment, while females’ decisions depended on the degree of similarity with their partners. Females compensated by provisioning more frequently in pairs of similar personality traits (i.e. accepting a high level of conflict), but reduced their provisioning investment in extremely dissimilar pairs. Our results promote a better understanding of the resolution of sexual conflict over provisioning and highlight the evolutionary significance of mating with similar partners based on certain personality traits.

International audience; The traditional view of sex roles and sexual selection emphasises the evolution of male ornaments as a result of female mate choice and male-male competition. Female ornaments are now receiving more attention, although their roles in mating decisions are still less well understood, especially considering cases in which colourful ornaments are expressed by both sexes. In this study, we analysed whether female skin coloration (luminance and redness of the face and hindquarters) influenced male mate choice and sexual behaviours in relation to intracycle (cycle phase), inter-cycle (number of consecutive cycles, conceptive nature of the cycle), and inter-individual (age, social rank, weight, and parity) variation in a captive social group of Japanese macaques (Macaca fuscata). Males did not preferentially choose darker/redder females. Moreover, males did not appear to use female skin coloration to apportion their mating efforts on the fertile phase of the menstrual cycle or during cycles that lead to conception, or to discriminate between females. Collectively, our results suggest that female skin coloration may not have been sexually selected in this species and that males mated regardless of such variation across females. To our knowledge, our study is among the few to report a lack of male choice for female coloration in a species where both sexes display ornamentation. Our findings provide novel insights on the role and evolution of female coloration in sexual signalling and mating decisions.

Swearing, cursing, expletives – all these terms are used to describe the utterance of taboo words. Studies show that swearing makes up around 0.5 % of the daily spoken content, however, the inter-individual variability is very high. One kind of pathologic swearing is coprolalia in Tourette syndrome (TS), which describes the involuntary outburst of taboo words. Coprolalia occurs in approximately 20–30 % of all patients with TS. This review compares swearing in healthy people and coprolalia in people with TS and is the first one to develop a multidimensional framework to account for both phenomena from a similar perspective. Different research findings are embedded in one theoretical framework consisting of reasons, targets, functions/effects and influencing factors for swearing and coprolalia. Furthermore, the very limited research investigating obscene gestures and copropraxia, compulsive obscene gestures, is summarized. New research questions and gaps are brought up for swearing, obscene gestures and coprophenomena.

Background: Estimating the changes in the levels of oxidative stress biomarkers are vital in identifying stress related disease in living organism. This study examined changes in the activity of antioxidant enzymes and lipid peroxidase level in female Wistar rats exposed to stressors of different nature were examined. Methods: 88 apparently healthy rats within the ages of 8-12weeks and weighing between 120-180g were utilized for the study. Rats were acclimatized for 2weeks and fed with rat chaw and water ad libitum. Animals were stressed at the rate of 1hr, 3hr or 5hr per day for 1, 2 or 3weeks respectively. After the experimental protocol of stress induction, the rats werekilled via cervical dislocation and some vital organs were carefully harvested for tissue homogenates in assessing SOD, CAT and MDA antioxidants. Data collected were analyzed using Mean±SEM, ANOVA was used to compare means and LSD was used for post hoc. Results: SOD activity of the different tissues examined were significantly (p

The preference tests have made a great contribution to promoting animal welfare. However, they are not always easily applicable and have some criticalities. Recently the anticipatory behavior has b...

We studied the effect of learning two symmetrical verbal relations in areading comprehension task. We explored emergence of intraverbals after 7- and 8-year-old children read ashort text with sente...

How environmental features (e.g., people, enrichment, or other animals) affect movement is an important element for the study of animal behavior, biomechanics, and welfare. Here we present a stationary overhead camera-based persistent monitoring framework for the investigation of bottlenose dolphin (Tursiops truncatus) response to environmental stimuli. Mask R-CNN, a convolutional neural network architecture, was trained to automatically detect 3 object types in the environment: dolphins, people, and enrichment floats that were introduced to stimulate and engage the animals. Detected objects within each video frame were linked together to create track segments across frames. The animals’ tracks were used to parameterize their response to the presence of environmental stimuli. We collected and analyzed data from 24 sessions from bottlenose dolphins in a managed lagoon environment. The seasons had an average duration of 1 h and around half of them had enrichment (42%) while the rest (58%) did not. People were visible in the environment for 18.8% of the total time (∼4.5 h), more often when enrichment was present (∼3 h) than without (∼1.5 h). When neither enrichment nor people were present, the animals swam at an average speed of 1.2 m/s. When enrichment was added to the lagoon, average swimming speed decreased to 1.0 m/s and the animals spent more time moving at slow speeds around the enrichment. Animals’ engagement with the enrichment also decreased over time. These results indicate that the presence of enrichment and people in, or around, the environment attracts the animals, influencing habitat use and movement patterns as a result. This work demonstrates the ability of the proposed framework for the quantification and persistent monitoring of bottlenose dolphins’ movement, and will enable new studies to investigate individual and group animal locomotion and behavior.

Non-human primates are highly threatened as a result of habitat destruction, agricultural expansion, industrial development, large-scale build-ups and wildlife trafficking. Nearly 60% of all primates are threatened and many are found in habitats with some form of human modifications (e.g., croplands and plantations). The adaptability of primates to survive in human-modified habitats is thus a key to determine their persistence in anthropogenic landscapes. In this study, we examined the population number and age-sex composition of the ‘Endangered’ Golden Langur Trachypithecus geei in a rubber plantation in the Kokrajhar District in Assam, India in 2016, and compared with past data of the langur population and demographics from the same location to better understand the population dynamics, demographic characters and persistence of the Golden Langurs in the rubber plantation. In 2016, we recorded six groups of Golden Langurs totaling 78 individuals with a mean group size of 13.00±4.00SD. Of the total population, 10.29% were adult males, 41.18% were adult females, 32.35% were juveniles and 16.18% were infants. The overall population growth from 1997 to 2016 was estimated to be 5.54% per year. Habitat matrices of rubber plantations with natural forest patches are important in the fragmented landscape for the persistence of Golden Langur populations. They may also act as a corridor for the langurs to move between the fragments and as food resources, highlighting the importance of such matrices for the langurs outside protected areas. Population monitoring and ecological studies in such matrices would therefore be needed for the successful implementation of targeted management strategies for the conservation of these threatened langurs.

Sheikh Jamal Inani National Park (Inani) is a wildlife habitat in Bangladesh located under the Cox’s Bazar South Forest Division, Cox’s Bazar. It constitutes significant habitat for the charismatic and globally ‘Endangered’ Western Hoolock Gibbon Hoolock hoolock in Bangladesh. Here, we show that Inani is a poorly-known gibbon habitat with a population of seven groups, comprising a total of 18 individuals. Among them, 77.8% were adults (males and females), and 11.1%, 5.6%, and 5.6% were sub-adults, juveniles, and infants, respectively, indicating low reproductive output. Five of seven groups had no offspring present in the group, and the mean group size of 2.57 individuals/group is low compared to other habitats in Bangladesh. Beside Western Hoolock Gibbon, Inani is home to many threatened wildlife species. The first record of the Slaty-backed Flycatcher Ficedula erithacus in Bangladesh occurred in Inani, adding this new species to the national bird checklist of Bangladesh. The presence of the globally ‘Endangered’ Asian Elephant Elephas maximus, Phayre’s Langur Trachypithecus phayrei, & Elongated Tortoise Indotestudo elongata and the globally ‘Vulnerable’ Northern Pig-tailed Macaque Macaca leonina, Capped Langur Trachypithecus pileatus, Indian Leopard Panthera pardus, & Asiatic Softshell Turtle Amyda cartilaginea highlight the importance of Inani as a conservation area in Bangladesh. The Western Hoolock Gibbon and other threatened wildlife of Inani are now on the verge of local extinction due to a sharp increase in forest resource extraction resulting from the recent influx of large numbers of Rohingya refugees from Myanmar, many of whom have settled around Inani. Through stakeholder interviews in the area, we have identified feasible and measurable conservation actions at Inani that are urgently needed to prevent further loss of wildlife and to protect this important gibbon habitat.

An increasing number of studies has focused on the after-effects of acute aerobic exercise on executive function. To date, empirical evidence lacks consensus regarding whether acute aerobic exercise has beneficial effects on executive function. To identify possible sources of this discrepancy, the present study focused on executive function demands and pre-test cognitive performance, and performed the first meta-analysis of individual participant data (IPD meta-analysis) in this area of research. Results indicated that the beneficial after-effects of acute aerobic exercise on cognitive performance were greater in participants with lower cognitive performance at pre-test. Acute aerobic exercise offered general benefits to cognitive performance irrespective of executive function demands, when pre-test cognitive performance was appropriately controlled. Thus, the present IPD meta-analysis suggests that pre-test cognitive performance is one possible source of the conflicting findings in acute exercise studies. Future research is encouraged to consider pre-test cognitive performance to avoid underestimating the beneficial after-effects of acute exercise.

What is the adequate terminology to talk about animal behaviour? Is terminology referring to mental or emotional states anthropomorphic and should therefore be prohibited or is it a necessary means to provide for an adequate description and should be encouraged? This question was vehemently discussed in the founding phase of Ethology as a scientific discipline and still is. This multi-layered problem can be grasped by using the concept of methodological signatures, developed by Köchy et al. (2016c). It is designed to analyse and systematically compare animal research approaches by examining their common parameters. By examining the works of Konrad Lorenz (1903–1989) and Nikolaas Tinbergen (1907–1988), this paper offers new insights both on a methodological and theoretical level. Methodologically, the application of the concept of methodological signatures is illustrated; theoretically, the principles of Classic Ethology are analysed. My aim is to illustrate how the problem of scientific access to animal subjectivity was addressed in the history of Ethology by analysing statements about animal sentience. For this purpose, I will first outline the general discussion about animal subjectivity and the tension between anthropomorphism and empirical adequacy. I introduce my own theoretical and methodological framework before presenting an analysis of Lorenz’ and Tinbergen’s methodological signatures. Thereby, I show how the question of terminology is deeply embedded in a network of epistemological, methodological and ontological concepts and establish key characteristics in regard to ethological approaches to animal subjectivity. Finally, I shed light on the possibility of using this typology to examine current frameworks of animal welfare research.

Small-scale comparisons help us to understand how habitat features and food availability impact primate abundance. This is particularly useful at sites without human impacts, as it allows for the investigation of the natural factors influencing nesting patterns and great ape abundance. We provide a small-scale study of sympatric great ape nests in an unlogged old-growth forest without poaching activities. We conducted a line transect survey (52 km total effort) around Mbeli Bai, a forest clearing in Nouabale–Ndoki National Park, Congo, applying on-site nest decay rates and assigning nest builder using logistic regression. We found a high occurrence of monodominant Gilbertiodendron dewevrei at Mbeli Bai (34%) that correlates with low great ape densities at Mbeli Bai. Chimpanzees (Pan troglodytes troglodytes) showed a preference for nesting in trees in closed canopy monodominant forest. We found a low percentage of gorilla (Gorilla gorilla gorilla) nests in mixed species forest (35%) and a higher percentage in trees (64%) compared to other study sites. However, generalized additive models found higher gorilla nest encounter rates in mixed species forest with dense understory than in monodominant forest and open understory. We found no indication of higher gorilla densities close to Mbeli Bai than elsewhere, and line transect estimates were lower than the number of gorillas revealed from direct observations. There were substantial differences between our findings and those for nearby sites, demonstrating the utility of small-scale comparisons to further understand the factors determining chimpanzee and gorilla densities within and between sites and the limitations of nest surveys.

Group-size effects, whereby antipredator vigilance decreases as group size increases, are widely reported in mammals and birds but a meta-analysis has only been conducted in birds. We systematically reviewed the literature on mammalian group-size effects, estimated the effect sizes in each study, and conducted a phylogenetic meta-analysis. We obtained 296 effect sizes from 97 species belonging to 10 Orders and 26 Families. Overall, effect sizes indicated a moderate negative effect of group size (r = −0.44), but 43% of the effect sizes were compatible with a null effect of group size. There was significant heterogeneity in effect sizes. Weaker effect sizes occurred when vigilance was measured as a frequency or a duration rather than as a percentage of time spent vigilant, when measured in closed habitats, during the reproductive season, and in mixed-sex groups or during times when juveniles were absent. We infer a “file drawer problem” because there were relatively few studies with smaller sample sizes reporting small group-size effects. The results confirm the importance of group size in explaining variation in mammalian vigilance but also suggest which a substantial amount of variation remains unexplained. We suggest that future studies should aim to study mammalian group-size effects by quantifying the percentage of time allocated to vigilance rather than lower-power methods such as frequency or duration of vigilance.

Phobia against spiders or snakes is common in humans, and similar phobia-like behaviors have been observed in non-human animals. Visual images of snakes elicit phobia in humans, but sensory modalities that cause snake aversion in non-human animals are not well examined. In this study, we examined visually induced snake aversion in two rodent species. Using a three-compartment experimental chamber, reactions to images of snakes were compared between the diurnal precocious rodent Octodon degus and nocturnal laboratory mice. The snakes whose images were presented do not live in the original habitats of degus or mice. Snake aversion was assessed by presenting snake vs. no-image, snake vs. flower, snake vs. degu, and snake vs. mouse images. The time spent in a compartment with the snake image and with the non-snake images were measured. Degus avoided images of snakes in every tests. In contrast, mice did not display snake aversion. Degus are diurnal animals, i.e., visual information is important for their survival. Since mice are nocturnal, visual information is less important for survival. Such behavioral differences in the two species may explain the difference in visually induced aversion to snakes. A principal component analysis of the stimulus images suggests that elementary cues, such as color, do not explain the differences in the species' aversion to snakes. Finally, snake aversion in degus suggests that aversion is innate, since the animals were born and raised in a laboratory.

A common pattern of reproductive aging is that reproductive performance increases during early life and reaches a peak, followed by a decline with age. Such quadratic reproductive aging patterns can differ among individuals. Moreover, if individual differences in reproductive aging patterns reflect individual-specific life-history trade-off strategies, they are also predicted to be associated with behavior according to the pace-of-life syndrome. For example, more active, aggressive, or bolder individuals may invest more in early reproduction, resulting in more rapid reproductive aging. In this study, we estimated individual differences in quadratic reproductive aging patterns and the relationship between reproductive aging and the activity of the virgin female bean bug (Riptortus pedestris) in the absence of mating costs. We found that the egg production of virgin females followed a parabolic trajectory with age and that individuals varied significantly in their quadratic reproductive aging patterns. In addition, we found that females that were relatively more active during early life invested in egg production more heavily at a young age and suffered from a sharper decline in egg production later in life. Thus, our results indicate that individual reproductive aging patterns may be a key component in the study of pace-of-life syndromes. We suggest that within-individual plastic characteristics of life-history traits such as reproductive aging patterns may explain the mixed results from multiple studies on pace-of-life syndromes.

Myotis nattereri represents a species complex that recently underwent taxonomic changes. Based on morphological evidence, two species were regarded to occur in the western Palaearctic; M. nattereri in Europe, Maghreb, Middle East, and Turkmenistan, and M. schaubi limited to Armenia and north-western Iran. Within M. nattereri sensu lato, several cryptic species were recently revealed using the morphological and molecular genetic approaches (M. escalerai, M. zenatius, M. crypticus, M. tschuliensis, M. hoveli), restricting M. nattereri s.str. to the temperate zone of Europe and the Balkans. Our aim was to complement the knowledge of diversity and distribution of the M. nattereri complex in the Middle East with help of molecular genetic (mitochondrial ND1 gene) and morphometric analyses. In this region, four genetic lineages of the complex belonging to two clades and three primarily size-defined morphotypes were confirmed in accordance with the previous studies. This mosaic represents four species, M. nattereri s.str., M. hoveli, M. tschuliensis, and M. schaubi, and all these species were demostrated to occur in allo- or parapatry to each other. Myotis nattereri s.str. was found only in western Anatolia and in the Aegean island of Samos. The occurrence Myotis hoveli was shown in the Levantine range of this species complex (Jordan, Israel, Syria, Lebanon, Cyprus, southern Anatolia) and also in the mountainous areas of eastern Turkey and northern Iraq. The range of Myotis tschuliensis represents a belt stretching from Crimea, via the Caucasus, Transcaucasia and northern Iran, to Turkmenistan. Myotis schaubi was confirmed only in its very restricted range in Iran and Armenia.

The problem of taxonomic differentiation in the order Primates is one of the important problems of evolutionary anthropology and primatology. The systematics of primates reflects their evolutionary relationships and allows to reconstruct the possible ways of formation of particular groups. Clarification of primate taxonomy involves a wide range of data, primarily from the field of morphology. Among the morphological features that distinguish particular taxa, the special role belongs to the system of craniological characters, which allow diagnosing the skulls in museum collections or fossil materials. The article is devoted to craniological identification of two species of the genus Chlorocebus: Chlorocebus pygerythrus (vervets) and Chlorocebus aethiops (grivets).

Background: A great amount of information is presented to psychology students through various mediums, often leading to misinformation and believing inaccurate psychological myths. Objective: We conducted two studies to examine psychomythology of psychopathology and whether mythbusting may be an effective pedagogical tool. Method: In Study 1, a total of 251 participants were recruited and asked about psychology myths they believed by using the Myths of Abnormal Psychology Questionnaire (MAP). In Study 2, a total of 46 students across two sections of abnormal psychology courses were asked about psychological myths they believed at the onset of class and at the end of class using the MAP. These students also were provided with an educational mythbusting intervention throughout the class. Results: Participants endorsed several myths of psychopathology and indicated that the greatest sources of their understanding came from instructors, the internet, movies, and mythbusting led to a decrease in myth endorsement. Conclusion: Students enter abnormal psychology courses believing several inaccurate myths and mythbusting appears to be a viable tool to address these misconceptions. Teaching Implications: Mythbusting can be implemented within abnormal psychology courses as an an engaging and effective teaching tool, as well as a means to model scientific thinking.

Eastern gray squirrels (Sciurus carolinensis) exhibit a variety of color morphs, including black. In the USA and UK, a common folk belief is that black squirrels are more aggressive than squirrels of other colors. We tested the biological basis of that belief using data from the 2018 Central Park squirrel census. Contrary to the belief, black squirrels do not chase other squirrels more often than do conspecifics of other colors. Black and non-black squirrels were equally likely to approach people for food and to display indifference to human presence, but black squirrels were more likely than non-black squirrels to flee from people. Although other research has found that aggression among squirrels increases when they live in higher population densities, black squirrels were no more aggressive than non-black squirrels despite the fact that they were sighted in parts of Central Park with higher squirrel population densities than other locations.

Many plant species have seeds embedded in their fleshy pulp to attract frugivores, which enhances the chance of seed dispersal. However, some tropical plants are evolved with sharp spines to avoid herbivores and/or to prevent water loss, which makes foraging by frugivores difficult. Such plants receive frugivores’ attention, either because of resource scarcity or adaptive behavioural plasticity. We have a limited understanding of how fruit-eating animals access fruits protected by spines. In this 1-year study, we describe bat foraging on a spiny tropical shrub, Ziziphus mauritiana (Rhamnaceae) whose dried branches are often used by the local people to capture bats in caves that inevitably damage their wing membranes. The greater short-nosed fruit bat, Cynopterus sphinx was the only visitor to this spiny plant during its fruiting season and predominantly extracted fruits using a hovering tactic (on 81% observations) without damaging wing membranes. The hovering enabled them to extract fruits quicker than when alighting on the tree. Bats carried all the fruits away from the parent tree to feeding roosts for consumption. Bat foraging has thus effectuated short-distance seed dispersal (range 11–70 m radii) in which most seeds (30.73%) were found at the distance of 31–40 m in our search up to 150 m. Although bats extracted both ripe and unripe fruits, ripe-fruit extraction was 4.5 × higher than the unripe fruits. This study shows the tradeoff between getting a good meal and contending with spines in a resource-scarce habitat. Besides, this study describes the adaptive foraging tactics of greater short-nosed fruit bats that facilitate short-distance seed dispersal.

Chemical cues can alert prey to the presence of predators before the predator is within visual proximity. Recognition of a predator’s scent is therefore an important component of predator awareness. We presented predator and control scents to wild, wild-born captive, and predator-naive captive-born pygmy bluetongue lizards to determine (1) whether lizards respond to reptile chemical cues differently from controls, (2) whether captive lizards respond more strongly to a known predator than to other predatory reptiles, (3) whether captive-born lizards recognise predators innately, whether captive-born lizards have reduced predator recognition compared with wild lizards and whether time spent in captivity reduces responses to predators, and (4) whether the avoidance response to predator detection differs between naive and experienced lizards. There was no significant difference in the number of tongue flicks to predator scent among wild, wild-born and captive-born lizards, suggesting that predator detection is innate in the pygmy bluetongue lizard and time in captivity did not reduce predator recognition. The number of tongue flicks directed towards brown snake scent was significantly higher than that to the novel and water controls for all lizard origins. Lizards of all origins continued to bask in the presence of predator scents, suggesting that chemical cues alone may be insufficient to instigate an avoidance response and other cues may be required.

Species of scorpionfly (Mecoptera) in the family Panorpidae perform wing-waving behaviors, whereby they rotate their front and rear wings at the same time. Previous studies have suggested that a male, which carries food for use as nuptial gifts for females, performs the wing-waving behavior when the male gives the gift to a female or competes with other males. However, when and how the wing-waving behavior occurs during a series of nuptial giftings and male–male competitions have not been investigated. Therefore, we here observed the role of wing-waving behavior during the processes of giving nuptial gifts and male–male competition in the Japanese scorpionfly Panorpa japonica in the laboratory and field. Unlike previous studies, only males performed wing-waving behavior toward females, while females did not exhibit the behavior in the wild. Also, males always performed wing-waving behavior before male–male competition. After a male–male competition, winner males continued wing-waving behavior, but loser males never performed the behavior against the winner male. A comparison of wing-waving behaviors before competitions between winner and loser males showed that the frequencies of wing-waving behaviors were higher in winner than in loser males. The present results suggest that the wing-waving behavior functions in the inter-sexual and intra-sexual selection in P. japonica. Digital video images related to the article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo210513pj01a and http://www.momo-p.com/showdetail-e.php?movieid=momo210513pj02a and http://www.momo-p.com/showdetail-e.php?movieid=momo210513pj03a.

Global climate change is altering patterns of temperature variation, with unpredictable consequences for species and ecosystems. The Metabolic Theory of Ecology (MTE) provides a powerful framework for predicting climate change impacts on ectotherm metabolic performance. MTE postulates that physiological and ecological processes are limited by organism metabolic rates, which scale predictably with body mass and temperature. The purpose of this study was to determine if different metabolic proxies generate different empirical estimates of key MTE model parameters for the aquatic frog Xenopus laevis when allowed to exhibit normal diving behavior. We used a novel methodological approach in combining a flow-through respirometry setup with the open-source Arduino platform to measure mass and temperature effects on 4 different proxies for whole-body metabolism (total O2 consumption, cutaneous O2 consumption, pulmonary O2 consumption, and ventilation frequency), following thermal acclimation to one of 3 temperatures (8°C, 17°C, or 26°C). Different metabolic proxies generated different mass-scaling exponents (b) and activation energy (EA ) estimates, highlighting the importance of metabolic proxy selection when parameterizing MTE-derived models. Animals acclimated to 17°C had higher O2 consumption across all temperatures, but thermal acclimation did not influence estimates of key MTE parameters EA and b. Cutaneous respiration generated lower MTE parameters than pulmonary respiration, consistent with temperature and mass constraints on dissolved oxygen availability, SA:V ratios, and diffusion distances across skin. Our results show that the choice of metabolic proxy can have a big impact on empirical estimates for key MTE model parameters.

Bats play crucial ecosystem services as seed dispersers, pollinators, controllers of insects, and nutrient recyclers. However, there has not been a thorough global review evaluating these roles in bats across all biogeographical regions of the world. We reviewed the literature published during the last two decades and identified 283 relevant studies: 78 dealt with the control of potential insect pests by bats, 80 related to the suppression of other arthropods, 60 on the dispersal of native or endemic seeds, 11 dealt with the dispersal of seeds of introduced plants, 29 on the pollination of native or endemic plants, 1 study on pollination of introduced plants, and 24 on the use of guano as fertilizer. Our literature search showed that queries combining the terms "seed dispersal," "insectivorous bats," "nectarivorous bats," "use of guano," and "ecosystem services" returned 577 studies, but half were experimental in nature. We found that the evaluation of ecosystem services by bats has been mostly conducted in the Neotropical and Palearctic regions. To detect differences across relevant studies, and to explain trends in the study of ecosystem services provided by bats, we performed generalized linear mixed models (GLMM) fitted with a Poisson distribution to analyze potential differences among sampling methods. We identified 409 bat species that provide ecosystem services, 752 insect species consumed by bats and 549 plant species either dispersed or pollinated by bats. Our review summarizes the importance of conserving bat populations and the ecological services they provide, which is especially important during the current pandemic.

Mammalian carnivores rely on their sharp teeth to effectively kill and consume prey. However, over time this causes wear and breakage that alters tooth shape, reducing their effectiveness. Extreme tooth wear and damage is especially prevalent in species that scavenge carcasses, like the Tasmanian devil (Sarcophilus harrisii), which are well known for their voracious appetites and ability to consume almost all of a carcass, including bone. In this study, we comprehensively describe tooth wear in captive and wild devils to look for differences in the patterns and rate of wear between these environments. To do this we surveyed tooth condition in skulls from 182 wild and 114 captive devils for which age was estimated using canine over-eruption. We found the types of tooth wear documented were the same in captive and wild devils, but captive animals have less severe wear than wild devils of the same estimated age. There was no difference in the proportion of captive or wild individuals with broken canine or molar teeth; however, breakage occurred at a younger age in wild devils. Although not considered anomalous or harmful, this indicates a difference in the way teeth are being used and/or the foods consumed between captive and wild devils. We hypothesize how these results relate to differences in diet or behavior that may stem from their various feeding environments, for example, higher quality food (fresh, whole, and yet to be scavenged carcasses) provided to captive devils likely causes less wear. Further, we support management options that closely replicate wild diet items and behaviors suitable for a long-term insurance population.

Age is a basic demographic characteristic vital to studies of mammalian social organization, population dynamics, and behavior. To eliminate potentially confounding ontogenetic variation, morphological comparisons among populations of mammals typically are limited to mature individuals (i.e., those assumed to have ceased most somatic growth). In our morphometric studies of treeshrews (Scandentia), adult individuals are defined by the presence of fully erupted permanent dentition, a common criterion in specimen-based mammalogy. In a number of cases, however, we have had poorly sampled populations of interest in which there were potentially useful specimens that could not be included in samples because they lacked associated skulls. Such specimens typically are associated with external body and weight measurements recorded by the original collectors, and we sought to determine whether these data could be used successfully as a proxy for age or at least to establish maturity. We analyzed four traditional external dimensions (head-and-body length, tail length, hind foot length, and ear length) and weight associated with 103 specimens from two allopatric populations of the Lesser Treeshrew (Tupaia minor Günther, 1876) from Peninsular Malaysia and from Borneo, which we treated as separate samples (populations). Individuals were assigned to one of eight age categories based on dental eruption stage, and measurements were compared among groups. In general, mean sizes of infants and subadults were smaller than those of adults, but the majority of subadults fell within the range of variation of adults. The large overlap among infants, subadults, and adults in external measurements and weight indicates that such measures are poor proxies for age in this species, probably for treeshrews in general, and possibly for other small mammals. This has significant implications for any investigation wherein relative age of individuals in a given population is an important consideration.

The loss of a companion animal results in millions of pet owners grieving annually. To date, little information has been synthesized on the grief response and coping mechanisms of bereaved pet owners. The aim of this review was to examine the relationship between pet loss and owner grief response. Major themes included: factors that influence the grief response, the disenfranchised nature surrounding pet loss, ambiguous pet loss and coping mechanisms used. Across the 48 studies included in this review, bereaved pet owners frequently reported feelings of embarrassment and loneliness following the loss of their pet. Types of coping mechanisms used by bereaved pet owners were identified and included: isolation, social support, continuing bonds, memorialization, religion, and relationships with other animals. Overall, this review was able to identify a consensus among the literature that bereaved pet owners are likely to experience disenfranchisement surrounding their loss. Based on the present findings, suggestions for future research include a focus on the effectiveness of coping mechanisms used by bereaved pet owners.

We trained eight pigeons (Columba livia) on a stagewise go/no-go visual discrimination task. A total of 16 visual stimuli were created from all possible combinations of four binary dimensions: brightness (dark/bright), size (large/small), line orientation (vertical/horizontal), and shape (circle/square). In the first stage, we presented S + and four S– stimuli: sharing one (brightness), two (brightness and orientation), three (brightness, orientation, and size), or no dimensional values with S + . In the second stage, all 16 stimuli were presented. In the first stage, stimulus discrimination was controlled by the number of dimensional disparities between non-rewarded stimuli and a rewarded one rather than by stimulus dimensional salience, whereas at the beginning of the second stage, pigeon behaviour was controlled mainly by dimensional reinforcement expectancy learned in the first stage. At the beginning of the second stage, pigeons correctly rejected 6–8 of 11 new added S- stimuli. A significant inverse correlation between the number of S– stimuli sharing dimension values with S + in the first stage and the dimensional discrimination ratios at the beginning of the second stage was found.

The fossil history of turtle and whale barnacles (Coronuloidea: Chelonibiidae, Platylepadidae, Coronulidae and †Emersoniidae) is fragmentary and has only been investigated in part. Morphological inferences and molecular phylogenetic analyses on extant specimens suggest that the roots of whale barnacles (Coronulidae) are to be found among the chelonibiid turtle barnacles, but the hard-part modifications that enabled early coronuloids to attach to the cetacean skin are still largely to be perceived. Here, we reappraise a fossil chelonibiid specimen from the Miocene of insular Tanzania that was previously referred to the living species Chelonibia caretta. This largely forgotten specimen is here described as the holotype of the new species †Chelonibia zanzibarensis. While similar to C. caretta, †C. zanzibarensis exhibits obvious external longitudinal parietal canals occurring in-between external longitudinal parietal septa that abut outwards to form T-shaped flanges, a character so far regarded as proper of the seemingly more derived Coronulidae and Platylepadidae. Along with these features, the presence of a substrate imprint on the shell exterior indicates that †C. zanzibarensis grasped its host's integument in much the same way as coronulids and platylepadids, albeit without the development of macroscopic parietal buttresses and bolsters. Thin section analyses of the inner parietal architecture of some extant and extinct coronuloids conclusively demonstrate that vestiges of comparable external parietal microstructures are present in some living members of Chelonibiidae. This observation strengthens the unity of Coronuloidea while significantly contributing to our understanding of the evolution of the coronuloid shell structure in adapting to a diverse spectrum of hosts.

Many sexual selection studies focus on conspicuous ornaments, such as long tails, but neglect to investigate inconspicuous traits. Here, we studied a well-known sexual selection mechanism, the Darwin–Fisher mechanism (i.e., breeding date selection), in relation to tarsus length in male barn swallows Hirundo rustica, a model species for sexual selection. When controlling for body size, we found that males with shorter tarsi started breeding earlier than those with longer tarsi. The current study indicates a selective advantage of short-legged males, explaining the reversed sexual dimorphism in tarsus length in this short-legged species.

People endorsing stronger beliefs in human supremacy over animals typically show less moral concern for animals. Yet how people think about different types of animals also depends on the role of the animals in society. For instance, people are less concerned about food animals than about companion animals. It is unclear, however, how human supremacy beliefs relate to this perceived moral divide between different types of animals. In two survey studies conducted in samples of British adults (N = 196 and N = 256), we tested whether human supremacy beliefs are associated with a greater perceived moral divide between high-status animals such as companion animals and low-status animals such as food animals. In both studies, participants rated the extent to which they felt obligated to show moral concern to a range of animals and completed the human supremacy beliefs scale. As expected, the results showed that participants felt more moral concern for companion animals (e.g., dogs and cats) and appealing wild animals (e.g., dolphins and chimps) than for food animals (e.g., pigs and turkeys) and unappealing wild animals (e.g., frogs and bats). Critically, confirming our hypotheses, this moral divide between high- and low-status animals was significantly larger for those holding stronger human supremacy beliefs. Furthermore, the effect of human supremacy beliefs held after controlling for gender, age, diet, and social dominance orientation. These findings suggest that beliefs in human supremacy over animals may serve as a legitimizing strategy to preserve not only the existing human-animal hierarchy but also greater hierarchical divides between animals.

The Pearl River Delta (PRD) region on the southeast coast of China has long been known as a highly productive fishing ground. Since the late 1980s, fishing pressure in the PRD has been intense, which warrants concerns of potential fishery-related impacts on the food resources and foraging ecology of apex marine predators in this region, such as the Indo-Pacific humpback dolphin (Sousa chinensis). In this study, we examined 54 stomachs with food remains, collected from beached carcasses of humpback dolphins recovered during fifteen years between 2003 and 2017. The 6043 identified prey items represent 62 teleost taxa, primarily small estuarine fish, but also larger reef fish. The dolphins appear to be opportunistic foragers, hunting across the water-column, with preference for shoaling and meaty fishes (e.g. Chrysochir aureus IRI% = 38.6%, Johnius belangerii IRI% = 23.1%, Mugil cephalus IRI% = 14.0%). Our findings suggest a dietary shift in recent years, from primarily demersal (as previously reported) to greater intake of neritic and pelagic fish. Dolphin foraging group size has decreased in recent years, which corresponds with declining size and numbers of prey items retrieved from dolphin stomachs. We suggest that these are indicators of declining food resources. Faced with a shortage of preferred prey, humpback dolphins may have broadened their dietary spectrum to maintain their daily energy intake, while their foraging group size decreased in response to the altered tradeoff between the costs and benefits of group foraging. This article is protected by copyright. All rights reserved.

Behavior analysts have long recognized the benefits of closely following their data; however, the data we are following may be moving faster than the tools we have to accurately analyze and predict future behaviors. This problem even saturates behavior-analytic investigations that focus on the evaluation of complex data related to public policy issues in areas such as poverty, geriatrics, and child welfare practice. In the face of this research enigma, there exists a more powerful and precise set of classification and prediction platforms for researchers in the behavioral sciences. In this article, we describe a combination of neural network strategies that predict child welfare professionals’ decision making. Extending the data analysis from the Yelick and Thyer (2019) study, we employed our current version of the Kohonen self-organizing map in conjunction with our deep neural network as a strategy for identifying participants who were at high probability for making heuristic decisions.

The most distant roots of neuroanatomy trace back to antiquity, with the first human dissections, but no document which would identify the thalamus as a brain structure has reached us. Claudius Galenus (Galen) gave to the thalamus the name ‘thalamus nervorum opticorum’, but later on, other names were used (e.g., anchae, or buttocks-like). In 1543, Andreas Vesalius provided the first quality illustrations of the thalamus. During the 19th century, tissue staining techniques and ablative studies contributed to the breakdown of the thalamus into subregions and nuclei. The next step was taken using radiomarkers to identify connections in the absence of lesions. Anterograde and retrograde tracing methods arose in the late 1960s, supporting extension, revision, or confirmation of previously established knowledge. The use of the first viral tracers introduced a new methodological breakthrough in the mid-1970s. Another important step was supported by advances in neuroimaging of the thalamus in the 21th century. The current review follows the history of the thalamus through these technical revolutions from Antiquity to the present day.

Chronic pain is a major global health issue that affects all populations regardless of sex, age, ethnicity/race, or country of origin, leading to persistent physical and emotional distress and to the loss of patients' autonomy and quality of life. Despite tremendous efforts in the elucidation of the mechanisms contributing to the pathogenesis of chronic pain, the identification of new potential pain targets, and the development of novel analgesics, the pharmacological treatment options available for pain management remain limited, and most novel pain medications have failed to achieve advanced clinical development, leaving many patients with unbearable and undermanaged pain. Sex-specific susceptibility to chronic pain conditions as well as sex differences in pain sensitivity, pain tolerance and analgesic efficacy are increasingly recognized in the literature and have thus prompted scientists to seek mechanistic explanations. Hence, recent findings have highlighted that the signaling mechanisms underlying pain hypersensitivity are sexually dimorphic, which sheds light on the importance of conducting preclinical and clinical pain research on both sexes and of developing sex-specific pain medications. This review thus focuses on the clinical and preclinical evidence supporting the existence of sex differences in pain neurobiology. Attention is drawn to the sexually dimorphic role of glial and immune cells, which are both recognized as key players in neuroglial maladaptive plasticity at the origin of the transition from acute pain to chronic pathological pain. Growing evidence notably attributes to microglial cells a pivotal role in the sexually dimorphic pain phenotype and in the sexually dimorphic analgesic efficacy of opioids. This review also summarizes the recent advances in understanding the pathobiology underpinning the development of pain hypersensitivity in both males and females in different types of pain conditions, with particular emphasis on the mechanistic signaling pathways driving sexually dimorphic pain responses.

When animals move along well-established pathways, sensory cues along the path may provide valuable information concerning other individuals that have used the same route. Yet the extent to which animals use pathways as sources of public social information is poorly understood. Here we quantified the responses of wild African savannah elephants, Loxodonta africana, to olfactory information along natural elephant pathways, habitual routes that link predictable critical resources in the environment. By monitoring the behaviour of elephants travelling on pathways in a predominantly male study population, we found that elephants were highly olfactorily responsive to pathway substrate. Lone travellers were more responsive than elephants travelling in groups, suggesting elephants without social companions may be more dependent on olfactory cues on pathways during navigation. Furthermore, by experimentally presenting olfactory cues on pathways we found that male African elephants exhibited focused olfactory responses to urine cues of same-sex conspecifics for at least 48 h from time of deposition, and that urine from adult elephants was more likely to elicit vomeronasal system responses than subadult urine. African elephants may therefore potentially be able to discern the age and maturity of individuals they can expect to encounter in the environment from remote urine cues on pathways. We suggest elephant pathways act as a public information resource, assisting navigating elephants via the depositing of urine and dung by previous travellers on the route. These results could help inform elephant management, which may manipulate olfactory information on pathways in high human–wildlife conflict areas, or could use olfactory urine cues to improve the efficiency of corridors that link protected areas for elephants.

In recent years, there has been a heightened interest in the effect of non-invasive brain stimulation on executive functioning. However, there is no comprehensive overview of its effects on different executive functioning domains in healthy individuals. Here, we assessed the state of the field by conducting a systematic review and meta-analysis on the effectiveness of non-invasive brain stimulation (i.e. repetitive transcranial magnetic stimulation and transcranial direct current stimulation) over prefrontal regions on tasks assessing working memory, inhibition, flexibility, planning and initiation performance. Our search yielded 63 studies (n = 1537), and the effectiveness of excitatory and inhibitory non-invasive brain stimulation were assessed per executive functioning task. Our analyses showed that excitatory non-invasive brain stimulation had a small but positive effect on Stop Signal Task and Go/No-Go Task performance, and that inhibitory stimulation had a small negative effect on Flanker Task performance. Non-invasive brain stimulation did not affect performance on working memory and flexibility tasks, and effects on planning tasks were inconclusive.

An integrated view of the stress response requires consideration of both the emotional and hormonal sequelae of stress, which are regulated by the hypothalamic-pituitary-adrenal (HPA) axis. Understanding the extent of the association between emotions and cortisol at the momentary level can shed light on the biopsychological pathways linking stress to health. Research in this area has adopted heterogeneous approaches and produced mixed findings; thus, it is critical to conduct a systematic review and meta-analysis. Systematic searches in major databases identified 22 studies (negative emotions [k = 19; 38,418 momentary observations]; positive emotions [k = 15; 31,721 momentary observations]). Meta-analysis found a significant positive association between momentary negative emotions and cortisol (r = .06, p.001) and a significant negative association between momentary positive emotions and cortisol (r = -.05, p = .003). No methodological differences moderated these associations. Our findings suggest that emotional states correlate with cortisol levels at the momentary level. We discuss the health implications of our findings and provide recommendations for advancing this area of research.

Captive mammals respond emotionally toward cognitive challenges, but research has precluded marine mammals. A potential indicator of emotion in toothed cetaceans is a large singular bubble (‘burst’) emitted from the blowhole, previously linked to surprise and excitement. Our study analysed bursts from a published study on dolphin cognitive enrichment (Clark et al., 2013). Bursts were only produced by task-engaged (72%) or task-spectating (28%) dolphins (n = 6 males in total). Burst frequency increased with the proportion of task engagement and spectator frequency, but not task progress or success (providing no evidence for an instantaneous ‘Eureka moment’). Bursts were reduced in frequency over three weeks, consistent with a decrease in task-engagement. Bursts were significantly more likely to come at the start of a bout of task-engagement than in the middle or end. We suggest bursts were an emotional response signaling dolphins’ instantaneous judgement of the task, more likely related to positive affect (interest, curiosity) than negative affect (frustration). They appear unrelated to respiration. It was unclear whether bursts were produced consciously and had a social function. We call for further dedicated research on the emotional valence of cetacean bursts. This will require simultaneous behavioural and acoustic measurements under different levels of more controlled challenge.

Observing interactions between others can provide important information to individuals. Male songbirds often engage in singing contests where they vary the type and timing of signals and provide eavesdropping individuals with information about their competitiveness. How this information is used and its effect on subsequent spatial behaviour and reproductive decisions of eavesdroppers is not well understood. Here we tested whether great tits use information gathered by eavesdropping on male singing interactions to assess rivals and (potential) mates. We used interactive playback experiments to engage territorial males in song contests with either a more (song overlapping and more persistent singing) or less challenging (song alternating and less persistent singing) intruder. We followed male and female movements by automated radiotracking, determined paternity using microsatellite analysis and maternal investment by quantifying egg weights and provisioning behaviour. We expected that mates of males exposed to the challenging treatment would subsequently foray more often off territory to assess other males and potential extrapair mates and invest less in their broods. Moreover, we expected that neighbours would adjust their foraying behaviour according to information gained by eavesdropping. Females, however, did not alter their foraying behaviour or brood investment and neither female nor male neighbours changed their visiting behaviour to playback territories. Our results provide no evidence that females used information gathered by eavesdropping on asymmetric song interactions in reproductive decisions or that song interactions affected movements across territories in the neighbourhood. Overlapping or singing for a longer time on an intruded upon territory may not always be perceived as a higher level of threat, and reproductive decisions and assessment of familiar individuals are likely to be based on multiple sources of information rather than on a single interaction.

Among social foragers, individuals can actively search for and find food (the producers) or join already discovered food patches (the scroungers). Compared to scroungers, producers often occupy more dangerous outer spatial positions in the group, but they benefit from the finder's advantage, which is the amount of food eaten before the arrival of others. Scroungers may occupy safer positions but they face feeding competition when joining a patch already occupied by others. Here, we report factors influencing intragroup spatial position, feeding strategies and feeding success for a group of wild vervet monkeys, C. pygerythrus, at Lake Nabugabo, Uganda. We collected data using behavioural observations and field experimentation (N = 132 trials) where we set up an artificial food patch with dispersed food rewards. We found that individuals who spent more time in the front-outer position of a moving group produced more. Producers that had a greater finder's time advantage (fed undetected by group members for longer periods) had a greater finder's advantage (consumed more food items before the arrival of other group members), and scroungers that arrived earlier had greater overall feeding success. We found that when the scrounger was higher ranking than other individuals at the patch, they used displacement scrounging (supplanted at least one individual from the patch to gain access to the food resource). However, feeding success did not differ between displacement scrounging and tolerated scrounging (when the scrounger fed at the patch with at least one other individual). Interestingly, we did not find higher-ranking individuals to have greater feeding success than lower-ranking individuals. Our findings corroborate previous studies showing that even among species with a linear dominance hierarchy and high occurrences of within-group contest competition, dominant individuals do not benefit from feeding advantages at large, dispersed food patches since they cannot monopolize the resource. Furthermore, our results emphasize the need to understand factors influencing feeding tolerance, particularly for subordinate individuals, who need to process ecological and social elements to maximize their food acquisition.

Given the high coexistence of anxiety symptoms in people with alcohol use disorder (AUD), we aimed to determine the influence of anxiety symptoms on outcomes in patients with AUD treated with the GABAB receptor agonist baclofen. A meta-analysis of 13 comparisons (published 2010-2020) including baseline and outcome data on alcohol consumption and anxiety after 12 weeks was undertaken. There were significantly higher rates of abstinent days in patients treated with baclofen compared to placebo (p = 0.004; high certainty evidence); specifically in those with higher baseline anxiety levels (p < 0.00001; high certainty evidence) compared to those with lower baseline anxiety levels (p = 0.20; moderate certainty evidence). The change in anxiety ratings over 12 weeks did not differ between those treated with baclofen or placebo (p = 0.84; moderate certainty evidence). This may be due to different anxiety constructs being measured by scales not validated in this patient group, or that anxiety is not a biobehavioral mechanism by which baclofen may reduce alcohol drinking. Given the prevalence of anxiety symptoms in AUD all these factors warrant further research.

Socialising a puppy is a challenge at the best of times, but particularly more so during lockdown. Veterinary and behaviour professionals can help owners prevent problem behaviours developing by raising awareness of canine body language, setting up first clinical exams to be positive experiences and providing tips on how owners can adapt social experiences to the individual.

Several hypotheses explain how sensory, anatomical and physiological constraints drive fruit preference in frugivores. Optimal diet theory (ODT) states that frugivores make decisions based on the energy contained in food. In contrast, geometry of nutrition (GN) states that animals balance their macronutrient intake instead, opting for rough energy. The defence trade-off hypothesis (DTH) assumes a negative relationship between secondary compounds and fruit preference. Finally, the size-matching hypothesis (SMH) states that frugivores are more attracted to fruits that are easier to handle and consume. We tested these four hypotheses by offering paired fruit species to three fruit-eating animal species in captivity that either chew fruit in the beak or mouth (‘masher’: 1 bird species, 1 bat species) or swallow whole fruits (‘gulper’: 1 bird species), from which we built a ranking of fruit preference. We then explored the importance of 13 fruit traits in explaining fruit preference. The masher bird was the only species whose fruit preference pattern corresponded with GN. Fruit preference of the masher and gulper bird species supported DTH and SMH, while fruit preference by the bat species was not related to any analysed trait. More than one single rule governs fruit preference in different frugivore species. Fruit preferences of functionally different frugivore species are affected by particular fruit traits, which they either select or avoid. The search for specific macronutrients, while avoiding toxicity in fruits matching the anatomical limitations of frugivores, could lead to complementary foraging choices. Variability between seed disperser species in their search for easily manageable fruits allows achieving a complementary fruit diet, with preferred and avoided traits. It can be an important driver of fruit trait diversity in fleshy-fruited plant assemblages.

Polyspecific associations, in which individuals of multiple species move together, have not been reported in Asian primates. However, only one study in India has shown this lack of association quantitatively. We collected data on interspecific encounters among 5 species of diurnal primates in Danum Valley by censusing 4 predetermined routes of 9.9 km, covering 1544.3 km, and tracking red leaf monkeys (Presbytis rubicunda) for 423 h over 25 mo. We tested the null hypothesis that the frequency and duration of encounters did not differ from chance levels. During censuses, we detected primates 373 times and found 2 species on the same 100-m segment only 6 times. This frequency was not significantly different from the chance level. While following red leaf monkeys, the frequency of encounters was lower than expected by chance with Mueller’s gibbons (Hylobates muelleri) but higher than expected by chance with Bornean orangutans (Pongo pygmaeus) in the nonfruiting season. Interspecific encounters accounted for 6.4% of tracking time, and the encounter duration was significantly longer than expected by chance for orangutans. Red leaf monkeys did not change their rate or direction of travel on meeting another species. We could not distinguish the association between red leaf monkeys and orangutans in the nonfruiting season from the possibility that the two species were independently attracted to the same place. In conclusion, we show the absence of active and consistent polyspecific association and identify avoidance in some species pairs in an Asian primate community.