It has been hypothesized that domestic dogs, Canis familiaris, are unusually flexible in their capacity to follow human communicative cues due to domestication, and comparing them to dingoes, Canis dingo, which are considered a remnant protodog, can provide unique insight into the early stages of speciation and how domestication has influenced cognition. Here, we investigated whether dogs and dingoes follow communicative cues at similar rates, which would suggest that communicative flexibility is conserved from their shared genetic history, or whether dogs outperform dingoes, which would suggest that domestication has contributed to dogs' ability to follow communicative cues. We first compared dogs' and dingoes' ability to follow a contralateral point and a marker (Study 1). In keeping with previous literature, we hypothesized that dogs would follow both cues, while dingoes would only follow pointing. We found that both species followed a marker above chance, while only dogs followed pointing. In a follow-up study (Study 2), we assessed how the presence of ostensive cues affected dogs' and dingoes' responses to a novel marker. We found that dogs' performance in the marker task was more dependent on ostensive context than that of the dingoes. These findings suggest that the presence of intentional, ostensive cues impact performance differently in dogs and dingoes, although it is unclear what mechanism underlies these performance differences. One possible hypothesis is that domestication has fine-tuned dogs’ sensitivity to human communication. Together, our findings suggest that the novel marker task might not be as strong a test of communicative ability as previously thought.
The understanding of habitat selection in wild vertebrates has been heavily influenced by observations of preferred foraging areas. However, foraging is only one of many ways animals interact with their environment, and preferences for habitat features that support resting, breeding and safety, along with trade-offs between these needs, remain underexplored. These trade-offs are likely to be particularly acute in complex environments where these needs are met in different locations. Using long-term data on group movements and individual life histories, we examine how preferences for foraging areas and burrow sites shape space use in Kalahari meerkats, Suricata suricatta. Meerkats rarely dig new sleeping and breeding burrows and must use those abandoned by other species, potentially generating trade-offs in daily space use if overnight refuges are far from optimal foraging areas. We show that space use is strongly anchored by burrow location, with burrows in white-sand habitats, particularly those in dry riverbed and pan habitats, preferred year-round while also being associated with low burrow switching rates. In contrast, foraging habitat preferences varied seasonally, with white-sand habitats often being disfavoured during foraging. Individuals also gained less weight in both wet and dry seasons when their morning foraging was concentrated in these habitats. As a result, meerkats faced a trade-off between optimal burrow locations and productive foraging grounds, which was reflected in faster, longer and more energetically costly travel when moving through or waking up in white-sand areas. Our results suggest that changes in the distribution or abundance of key burrow-constructing species in desert environments may have cascading effects on the many secondary burrow users that depend on them for survival and reproduction. More broadly, our results highlight that refuge availability can impose strong ecological constraints on animals and may restrict behavioural plasticity under environmental change, particularly if productive foraging areas shift.
Vocalizations made during copulation (copulation calls) are a widespread behaviour among mammals and birds. The function of copulation calls has been little studied, although it has been suggested that they serve as complex communication between partner individuals and even between nonpartner individuals. Functions such as territorial signalling and intersexual attraction have been proposed for copulation calls. We examined the function of copulation calls by investigating how wild Ryukyu scops owl, Otus elegans, respond vocally to recordings of copulation calls given by nonpartner individuals. This is the first avian study examining sexual differences in responses to copulation calls. Playback experiments indicated that both male and female individuals of established pairs responded more strongly to playback of sounds including copulation calls than to playback of sounds without copulation calls. The rate of change in the onset of vocal response was significantly greater for males than for females, whereas no significant sex differences were found in the number of responses and the duration of responses. These results suggest that copulation calls may function in territorial signals, eliciting strong vocal responses from both nonpartner males and females. Ryukyu scops owl give copulation calls (at a rate of 0.198 times/h) only during the prelaying period from February to April. During experiments using playback of duet calls, territorial breeding individuals responded at an increased frequency of 1.45 copulation calls/h. This increased rate of response also suggests that copulation calls may serve as territorial signals.
Interspecific communication plays an important role in mediating human–animal interactions, particularly in contexts involving access to anthropogenic resources. This study examined begging behaviour in free-ranging dogs in urban India, focusing on how social context, dog sex, experimental condition and experimenter gender influenced total begging time and the proportion of begging expressed as active solicitation. We observed 650 adult dogs and analysed begging behaviour using beta-binomial generalized linear mixed models. Solitary dogs spent a greater proportion of the observation period begging than dogs observed in groups, and females begged more than males. However, among dogs that begged, solitary individuals showed a lower proportion of active begging than dogs in groups, suggesting that solitary dogs begged for longer overall whereas group-living dogs showed a relatively greater active component when begging occurred. Experimental condition did not significantly influence either total begging time or active begging proportion. Experimenter gender also did not significantly affect total begging time, although dogs showed a marginal tendency to display lower active begging towards male experimenters. A survey of 841 local residents showed that female respondents were more likely than male respondents to report feeding street dogs, providing social context for possible gendered variation in dogs’ prior experience with humans. Overall, our findings suggest that begging behaviour in free-ranging dogs is shaped more strongly by social context and dog sex than by the immediate gaze and food cues tested here. These results highlight the context-dependent nature of dog–human interactions in human-dominated environments.
Environmental enrichment has become an essential tool for maintaining captive animals and improving their welfare. The information necessary to implement enrichment practices is largely restricted to a few species, mainly mammals, while studies on reptiles lag behind. However, current research shows that reptiles, like other species, can benefit from well-designed enrichment. In this study, we evaluated the effects of three types of enrichment on welfare-related indicators in the European common wall lizard, Podarcis muralis, including behavioural measures and faecal corticosterone metabolites (FCMs). We used chemosensory (conspecific scents), thermal/structural (basking platforms) and nutritional (feeding device) enrichment designed to provide ethologically relevant challenges. All enrichment interventions yielded a significant decrease in abnormal behaviour (interacting with transparent boundaries) and a significant increase in exploration compared to baseline, indicating improved welfare. FCM levels increased with time spent in captivity, but less markedly when lizards were exposed to enrichment than when it was absent. Taken together, our results suggest positive effects of all three enrichment types and highlight the importance of using an ethologically informed approach to enrichment design. We discuss how, when grounded in species-specific knowledge, similar strategies can contribute to improving welfare in a broader range of captive reptiles.
In animal communication, including human conversation, vocal exchange is a key phenomenon that organizes interactions so that partners exchange rapidly, taking turns and avoiding overlapping vocalizations. By contrast, vocal exchanges in cetaceans have generally been reported to involve frequent overlapping vocalizations. However, it remains unclear whether animals overlap their vocalizations incidentally or actively. Here, we explored the behavioural mechanisms underlying vocal overlapping during vocal exchange in common bottlenose dolphins, Tursiops truncatus. We first identified the signature whistles of five captive dolphins and then conducted a playback experiment in which a separated individual's signature whistle was played to dolphins housed together in the focal pool. The observed rate of vocal overlap was significantly higher than expected by chance, indicating that overlap did not occur incidentally. Analysis of spontaneously produced signature whistle sequences showed that dolphins produced whistles with isochronous timing, and that this isochrony exceeded that of a random model. This indicates that dolphins naturally produce signature whistles isochronously. We then evaluated two possible explanations for vocal overlap: dolphins might overlap by predicting the timing of a partner's next whistle, or by responding rapidly after hearing the next whistle, even before it had ended. However, in a playback experiment comparing vocal responses to isochronous versus nonisochronous sequences, the frequency of overlapping did not differ between conditions. This suggests that isochronous temporal regularities in vocal sequences did not facilitate prediction of the timing of the partner's next whistle and that vocal overlap is better explained by rapid responses following detection of conspecific whistles. These findings suggest that bottlenose dolphins, like other taxa, exchange vocalizations to reduce response delay. However, unlike most other species, they do not avoid overlapping and instead incorporate it into the vocal exchange. This study provides new comparative insight into both the universality and the diversity of vocal exchange patterns across species.
Individual variation in behaviour is the substrate for selection. In bottlenose dolphins, individuals have been shown to have repeatable behavioural strategies that persist over decades. To what extent might such persistent individual differences impact maternal care (i.e. the presence of maternal style), or is care instead determined more by calf characteristics? Based on 40+ years of study of Indo-Pacific bottlenose dolphins, Tursiops aduncus, in Shark Bay, Australia, we investigated the repeatability and demographic drivers of maternal care and their impact on postweaning survival. Using focal follow data (N = 428 follows) of 22 mothers of 68 calves, we examined maternal behaviour when calves were <2 years old. Behavioural metrics included infant position, a type of mother–infant contact and a ‘carrying’ behaviour used as a proxy for direct maternal care, time spent together (within 10 m) and behaviour while together. Maternal care metrics were not individually repeatable; rather, calf characteristics such as age and condition were more important in determining the amount of maternal care. Calves that did not survive to age 4 (average age of weaning in this population) and those who weaned later than average received more direct maternal care than those who survived, suggesting mothers try to compensate for calf condition with increased care. In summary, unlike altricial mammals where mothers have direct control over offspring (by carrying and caching), patterns of maternal care are largely driven by the attributes of the calf in this precocial species.
Natural selection encompasses a range of evolutionary processes that lead to differential survival and reproduction via ecological, sexual and social selection pressures. We argue that, despite playing a demonstrably profound role in the evolution of social species, social selection has not been sufficiently integrated into the broader evolutionary paradigm as a driver of evolutionary changes. Here we review social selection, including its various descriptions in the literature, and propose a new, unifying definition: social selection comprises the selection pressures imposed by the social environment, which are determined by group characteristics and/or any interindividual social interactions that lead to differential fitness for an acting individual and/or their groupmates. We additionally review how self-reinforcing social selection can generate a runaway process, and provide a second definition for runaway social selection. We argue that social selection illuminates behavioural evolution, potentially driving the evolution of complex sociality and offering insights into social systems beyond those gained from ecological or sexual selection alone.
Animals master various numerical tasks. Among numerical abilities, ordinality enables animals to identify an item on the basis of its position in a sequence (e.g. selecting the second out of six), a skill crucial for navigation, documented in species such as domestic chicks, fish and honey bees. Domestic pigs, Sus scrofa domesticus, exhibit advanced spatial and navigation skills. However, their ability to use ordinal information remains largely unexplored. Here, we trained 16 free-ranging Kune Kune pigs in an ordinal task. Seven pigs learned to select the second, and nine pigs the fifth bowl in a sagittal sequence of six identical bowls. When the sequence displacement was identical to the training one (sagittal test), both groups significantly preferred the previously reinforced bowl in the absence of visual or odour cues. When the distances between the bowls were manipulated, so that the ordinally correct and the spatially correct bowl did not coincide (ordinal–spatial incongruence test), pigs relied on spatial cues. Some individuals potentially relied on ordinality, suggesting that pigs can use ordinal information even though spatial information use predominates. When the sequence was rotated by 90°, so that it was oriented frontoparallel with respect to the pig's starting position (frontoparallel test), both groups preferentially approached the second bowl on the right side of the arena, hinting at hemispheric specialization for food-related and/or spatial tasks. Future studies should follow up on the relevance of, and preference for, numerical and spatial cues in pigs as well as on the origins of pigs' right-side preference in ordinal foraging tasks.
Urbanization is one of the most important forms of human-driven landscape change, altering wildlife populations in unprecedented ways. In terms of behaviour, urbanization is hypothesized to increase the likelihood of observing urban populations touching, exploring and solving novel food-related tasks compared to rural ones. However, little is known about the impact of spatiotemporal patterns of urbanization, particularly historical patterns of change, on these behaviours. We tested this in the world's most urbanized carnivore, the red fox, Vulpes vulpes, by introducing novel food-related tasks (puzzle feeders) to 284 sites throughout Great Britain. We compared tactile and problem-solving behaviours in rural populations, recently colonized urban populations and long-established urban populations (>40 years). Foxes from 27.4% of locations touched the tasks and foxes from 12.4% of locations solved them. Urban foxes were more likely than rural ones to touch tasks. Exploration time, exploratory diversity and latency to touch tasks did not differ significantly across urban and rural locations. Urbanization rate from 1994 to 2020 (26 years) did not significantly predict the likelihood of foxes touching or solving tasks across locations. Older urban populations, particularly from London, spent more time exploring tasks and displayed greater exploratory diversity and higher problem-solving success, despite more recent urban populations being equally likely to touch them. Collectively, our findings suggest that certain population characteristics, such as the likelihood of touching/engaging with novelty, potentially emerge early in urbanization while other characteristics, such as greater exploratory and innovative behaviours, may emerge after long-term urban exposure across many decades.
Predation represents a major selective force for animal populations, with direct consequences on their dynamics and evolution. In most mammal species, antipredatory tactics are expected to be exacerbated in reproductive females, due to parental care and higher fitness cost of predation. Several studies on mountain ungulates have identified steep rocks as elective antipredatory refuges. We used GPS-determined movement behaviour to test the use of refuge areas in Alpine ibex, Capra ibex, from a colony in the eastern Italian Alps (Marmolada massif). We compared movements of reproductive and nonreproductive female ibex along an altitudinal gradient and with respect to refuge areas throughout the spring–summer phases of the reproductive cycle, and between daytime and night-time. Regardless of their reproductive status, females moved towards higher elevation during the peak of the summer and to lower elevation at night at the diel scale. However, reproductive females exhibited a smaller altitudinal shift between day and night and stayed closer to the refuge areas, both during the day and at night, but only after births and during the more demanding phases of reproduction (lactation). We argue that this behaviour is related to females' need to protect their kids from predators because of their kids’ lower mobility, especially in the first phases after birth. By contemporarily showing that differences both in the use of refuge areas and altitude used (linked to resource availability and temperature) between reproductive and nonreproductive females vary throughout the maternal phases, our results also support a resource acquisition–thermoregulation–predation risk trade-off.
Conspecific brood parasitism is a reproductive tactic in which a female lays an egg in the nest of a conspecific host. This may be costly for host females, especially in altricial species, as the number of fledglings depends on the parents' capacity to feed them. Consequently, several counterstrategies have evolved, such as nest guarding or egg ejection. The ‘fear of feathers hypothesis’ proposes that white feathers in a nest may affect conspecific brood parasitism rates as they repel visitors to nests in several passerine species, perhaps by indicating a recent predation event. In this study, we tested this hypothesis in the spotless starling, an altricial passerine. Following an observational study that confirmed the natural nest decoration behaviour of spotless starlings, we manipulated the content of nests, adding or removing feathers, to determine their effect on parasitism rates. We found no significant effect of white feathers alone. However, we found that nests containing feathers (all colours combined) were visited less by intruders and parasitized less than nests without feathers. This result suggests an effect of feathers on host nest selection by spotless starling parasites. Parasites may, for example, use feathers as a cue to recent predation or as an indicator of the nesting stage to synchronize their laying with that of the host. Further research is needed to determine whether all feathers have the same impact and whether host females can select the best feathers for defending their nest.
Mutualistic interactions have played a central role in generating biodiversity and are often facilitated by an exchange of information between participating parties. Cues and signals are likely to be particularly crucial in animal interspecies cooperation, a specific form of mutualism that depends on real-time, interactive behavioural coordination to secure mutual benefit. Yet, despite the taxonomic breadth and ecological significance of these interactions, our understanding of the roles of cues and signals in animal interspecies cooperation remains relatively underexplored compared to their well-documented roles in other mutualisms, intraspecies cooperation and interactions involving collective behaviour. Here, we examine the ecology and evolution of cues and signals in animal interspecies cooperation. Drawing on diverse natural history examples, we first assess the ecological functions, benefits and costs of cues and signals, and discuss how the information they convey about partner identity, motivation and reliability informs decisions about whether, when and how to cooperate with heterospecifics. Second, we outline the evolutionary origins, variation and heritability of cues and signals, and discuss the potential for coevolution between signallers and perceivers. Third, we draw on relevant insights from broader mutualisms and cooperation within species to highlight key similarities and differences in the use of cues and signals across interaction types. Overall, our review clarifies how information underpins animal interspecies cooperation, highlights key gaps in the scientific literature, and identifies promising avenues for future research on its ecological and evolutionary significance.
Studies of birdsong have long focused on long-range signals used for attracting mates and defending territory, but recent research has highlighted the importance of soft songs in social bonding and pair maintenance. Even for species that sing softly, courtship is a context in which enhanced vocal output can be beneficial. Indeed, many bird species modulate their song amplitude according to the social context. However, it remains unclear how this amplitude plasticity interacts with the biomechanical demands of producing structurally complex vocalizations. Here, we investigated how song performance changes with the social context in the star finch, Bathilda ruficauda, an estrildid species that produces soft songs with highly complex syllables. Comparing undirected songs and female-directed songs, we examined whether males increase amplitude during courtship and, if so, whether this modulation induces changes in other spectrotemporal parameters due to parameter couplings and potential biomechanical trade-offs. We found that males produced female-directed songs with higher amplitude than undirected songs, but the difference was strikingly small. Notably, this amplitude increase was accompanied by a reduction in Wiener entropy, while other spectral parameters remained unchanged. These results suggest that star finches operate near a biomechanical ceiling where further increases in vocal amplitude would compromise syllable complexity. We propose that, in star finch courtship, structural song complexity may be prioritized over vocal amplitude. Given that star finch courtship occurs only at close range and also involves visual signals, the selection pressure for high amplitude may be relaxed. Overall, our findings highlight the functional diversity of birdsong and the need to broaden our understanding of avian vocal performance. Ultimately, we advocate overcoming the research bias regarding territorial birds with loud broadcast songs in order to gain a more comprehensive insight into the behavioural ecology of birdsong.
Temperature is an important abiotic factor constraining animal physiology, yet its impact on social dynamics remains largely unexplored in wild endotherms. Here, we investigated the effect of temperature on social interactions of Alpine marmots, a cooperative breeder highly adapted to cold environments. We collected 667 social interactions during 189 h of observation of 14 family groups, combined with temperature records from June 2023, 2024 and 2025. We analysed these data using generalized linear mixed models to test thermal effects across four different social behaviours (i.e. play, agonistic, greeting and grooming). We found that temperature acts as a nonuniform constraint on sociality. While essential behaviours required for group stability (i.e. grooming, greeting and agonistic) were buffered against thermal stress, facultative behaviours (i.e. play) were suppressed. Specifically, play activity peaked at 12.8 °C and interactions/h collapsed to near zero as temperature rose above 21 °C. These results suggest that, in Alpine marmots, play may be the first social behaviour to decline under heat stress. Consistent with the surplus resource theory, play is a labile trait that occurs only in a ‘relaxed field’ and is prone to be sacrificed under stressful conditions. As play is essential for the acquisition of motor and social skills in immature individuals, its reduction may lead to long-term developmental deficits. With this study, we propose that the decline of play interactions may serve as an early bioindicator of thermal stress in Alpine marmot populations, highlighting how global warming can compromise social dynamics before affecting demographic parameters.
In social animals, maintaining strong bonds with conspecifics can be important for reproduction and survival. However, it remains unclear how best to quantify these bonds. Existing social network techniques typically focus on building robust overall networks of co-occurrences but approaches that maximize whole-network accuracy may not be optimal for detecting the most important bonds between individuals. We used data from winter social interactions in a population of spotless starlings, Sturnus unicolor, fitted with passive integrated transponder tags and detected at feeders using radio frequency identification loggers to evaluate existing methods and develop new methods for extracting co-occurrence data from temporal streams of detections. We aimed to develop a method capable of extracting key social bonds: pairs of males and females that bred in consecutive springs. Our results show that although all approaches can differentiate most known pair bonds from other social relationships, methods that focus on capturing fine-scale associations are most effective at delineating them. We then applied this method to birds that were found breeding in spring with a new partner, revealing that in over half of these newly formed pairs, individuals within a pair were each other's strongest social associate during the preceding winter. Applying a discriminant function analysis to the best performing network method demonstrated good sensitivity for identifying true pair bonds. However, we also found substantial variation in social association patterns among pairs, including differences in the formation and dissolution of bonds across the nonbreeding season. Our method improves on previous approaches while also adding to the growing evidence that pair bonding is a complex process that can begin well before the onset of breeding.
Bats navigate in darkness by steering their sonar beams, but how head–beam coordination varies across species with contrasting emission systems remains poorly understood. We examined the oral-emitting FM bat Miniopterus fuliginosus (family Vespertilionidae) and the nasal-emitting CF-FM bat Rhinolophus nippon (family Rhinolophidae) during free-flight obstacle avoidance. Using a motion capture system to track head direction and a 24-channel microphone array to reconstruct sonar beam direction, we quantified angular offsets defined as the angle between head direction and pulse emission direction. Miniopterus fuliginosus exhibited tight head–beam coordination, validating assumptions from head-fixed studies. By contrast, R. nippon showed substantially larger offsets together with a significantly narrower horizontal beam width, a morphological and acoustic constraint that reduces instantaneous spatial coverage. Correspondingly, R. nippon actively shifted its beam between pulse groups, compensating for this restricted beam width and achieving spatial exploration comparable to the broader-beamed M. fuliginosus. Our findings demonstrate divergent acoustic gaze strategies: FM bats employ stable head–beam coordination, while CF-FM bats achieve flexible beam steering. These results highlight how emission mode and flight morphology jointly shape sensorimotor strategies for spatial perception in complex environments, providing evidence for species-specific adaptations in echolocation.
Human–wildlife conflicts in urban settings are increasing and sometimes cause injury or mortality for people and wildlife. Conflicts may be exacerbated by large increases in outdoor human recreation, such as during the COVID-19 pandemic, when people were prevented from gathering indoors and made increasing use of parks. This appears to have occurred in Vancouver's Stanley Park, British Columbia, Canada, where an unprecedented 45 coyote, Canis latrans, attacks on humans occurred between December 2020 and August 2021. To understand how this situation arose and might predict similar future problems, we compared reported aggressive human–coyote encounters and coyote sightings in Stanley Park from 2020 to 2021. We sought to identify predictors of aggression among spatial and temporal variables associated with human activity and coyote behaviour. We also compared characteristics of human victims of attacks to those of park users in 2024. Coyote aggression was higher (1) during pandemic restrictions on indoor gatherings (associated with higher human activity outdoors), (2) on trails with greater human activity, (3) during times of the day and week with relatively low human activity and (4) in areas closer to coyote dens and farther from potential sources of anthropogenic food, including garbage bins and picnic areas. While proximity to anthropogenic food sources did not positively predict aggression, anecdotal reports described the behaviour of the aggressive coyotes as likely food-conditioned. Relative to observed park users, victims of coyote attacks were more often running and alone when attacked, but there was no effect of a person's age or gender, or of domestic dog presence. Our results suggest coyote aggression in Stanley Park likely resulted from a combination of habituation, den defence, opportunistic predatory behaviours, and possibly food conditioning. To avoid similar situations in the future, wildlife managers could encourage the public to recreate in groups, during peak-use hours and away from known den sites.
