Animal Behaviour

Innovativeness and social learning are the pillars of cultural evolution. While the role of social tolerance in social learning has long been acknowledged, its impact on innovativeness remains poorly understood. Here, we test six groups of captive white-faced capuchins (Cebus capucinus) and brown capuchins (Sapajus apella) to explore and compare the relationship between social tolerance and problem-solving propensities. White-faced capuchins are renowned for their rich repertoire of social behaviours, whereas brown capuchins are known for their diverse foraging repertoire, resulting in a broad range of culturally transmitted behaviours in both species. We performed a co-feeding experiment to assess species differences in social tolerance and a set of open diffusion novel food puzzles to test innovativeness. We measured associations for each possible dyad within each group during both experiments and compared the resulting social networks between conditions. We also measured neophobia in an independent experiment presenting groups with three novel objects. Overall, during both experiments, brown capuchins were more tolerant, and proportionally more individuals spent their time within the testing areas at any given moment. We also found that networks across experimental contexts were more similar in brown capuchins compared to white-faced capuchins. Moreover, although differences in approaching and exploring food puzzles were marginal, the success rate was higher in brown capuchins than in white-faced capuchins. Finally, neither eigenvector centrality within the networks nor neophobia could explain individual problem-solving success. Age was the strongest predictor for successfully extracting a food item. The results indicate that species-level differences in social tolerance may contribute to divergent innovation patterns, whereas individual-level variation within species may have only a minor influence. We conclude that the higher social tolerance observed in brown capuchins during feeding and foraging contexts can contribute to their broader repertoire of foraging behaviours and foraging traditions. Data availabilityAll data needed to evaluate the conclusions are present at OSF (https://doi.org/10.17605/OSF.IO/BY5MJ). Declaration of InterestThe authors declare no competing interests. Author ContributionsSandro Sehner: Writing - original draft, review & editing, Conceptualization, Methodology, Formal analysis, Data curation, Funding acquisition. Claudia Fichtel: Writing - review & editing. Peter Kappeler: Writing - review & editing. Helene Meunier: Writing - review & editing, Conceptualization, Methodology.

Understanding the emotional states of animals is key for informing their ethical treatment, but very little attention has been directed towards the emotional lives of invertebrates. As emotions influence information processing, one way to assess emotional states is to look for an individuals cognitive bias, i.e., their tendency to make optimistic or pessimistic judgements. Here we developed a free-running judgment bias task for the ant Lasius niger, and applied the judgement bias to assess ants reactions towards positive and negative stimuli. After an initial learning phase in which individuals were trained to associate two odour stimuli with positive or negative reinforcement, their reaction towards ambiguous stimuli, i.e., a mixture between both odours, was assessed. We also explored our study species capacity to socially transmit emotional states ( emotional contagion) by investigating whether social information could elicit emotional responses. We find L. niger to be optimistic, showing a baseline positive judgement bias, with 65-68% of ants preferring an ambiguous 1:1 mix of positive and negative cues over no cues. Providing an unexpected food reward prior to the judgement bias task increases positive judgement bias (c. 75% positive). There was a non- significant tendency towards a negative judgement bias after experiencing a mild electric shock (c. 75% negative). Neither positive nor negative social information (trail and alarm pheromones, respectively) affected the ants judgement biases, thus providing no indication for emotional contagion. The development of a powerful, simple, and ecologically relevant cognitive judgement task, deployable in the lab and in the field, opens the door to systematic comparative studies of the evolutionary and ecological causes of judgement bias.

BackgroundThe ability to respond plastically to environmental variation is a key determinant of fitness. Females may use cues to strategically place their eggs, for example adjusting the number or location of eggs according to whether other females are present, driving the dynamics of local competition or cooperation. The expression of plasticity in egg laying patterns within individual patches, i.e., in contact clusters or not, represents an additional, under-researched and potentially important opportunity for fitness gains. Clustered eggs might benefit from increased protection or defence, and clustering could facilitate cooperative feeding. However, increased clustering is also expected to increase the risk of over-exploitation through direct competition. These potential benefits and costs likely covary with the number of individuals present, hence egg clustering behaviour within resource patches should be socially responsive. We investigate this new topic using the fruit fly Drosophila melanogaster. ResultsOur mathematical model, parameterised by data, verified that females cluster their eggs non-randomly, and increase clustering as group size increases. We also showed that, as the density of adult females increased, females laid more eggs, laid them faster, and laid more eggs in clusters. Females also preferred to place eggs within existing clusters. Most egg clusters were of mixed maternity. ConclusionsCollectively, the results reveal that females actively express plasticity in egg clustering according to social environment cues and prefer to lay in clusters of mixed maternity, despite the potential for increased competition. These findings are consistent with egg clustering plasticity being selected due to public goods-related benefits.

Decision making can have significant fitness consequences across various aspects of animal life. For acorn ants, Temnothorax curvispinosus, choosing a new nest quickly and accurately can affect the survival and fitness of the whole colony. When emigrating, ants consider several nest attributes such as cavity shape, thickness, and brightness. Ants may benefit from having more attributes differentiating potential nests only if they can quickly and accurately assess all possible attributes and make well-informed decisions. Here, we asked if the number and type of attributes differentiating potential nests affect the accuracy and latency of colony decision-making. We used pair-wise tests, where potential nests differed in 1-3 attributes, with one nest within the pair considered less optimal. We recorded the nest the colonies chose and the time it took to make the decision. We found that the degree of difference did not affect the decision-making latency, suggesting that ant colonies searching for a new nest might be constrained temporally when selecting a new nest site. We also found that accuracy increased with the number of attributes, particularly when nest brightness was manipulated, indicating that increasing the number of attributes may help facilitate nest-site selection.

The social complexity hypothesis posits that complex social systems (that entail high uncertainty) require complex communicative systems (with high vocal flexibility). In species with fission-fusion dynamics, where the fluid composition of temporary subgroups increases the uncertainty with which group members must manage their social relationships, vocal communication must be particularly flexible. This study assessed whether contact call rates vary with caller and audience characteristics in free-living spider monkeys, as well as with fission and fusion events. Adult females and immature individuals called more when in small audience settings, while audience size did not influence adult males. Adults called more when in the presence of the opposite sex, whereas immatures vocalized more in subgroups composed only by females. Females also called more when with their mature sons. We found higher call rates in periods during which fission and fusion events took place than in periods with more stable compositions and when the composition after a fission or fusion event changed from one sex to two sexes. A flexible use of contact calls allows individuals to identify themselves when they join others, particularly if they are members of the opposite sex. This socio-spatial cohesion function reduces the uncertainty about subgroup composition.

ObjectivesBonobos (Pan paniscus) are unique among non-human primates in that females exhibit prolonged sexual receptivity to males during the postpartum infertile stage. Although high synchrony in female sexual receptivity has been hypothesized to constrain dominant males monopolization of reproductive success, recent genetic studies indicate pronounced male reproductive skew in this species. We investigated how prolonged sexual receptivity in female bonobos affects male behavioral patterns. Materials and MethodsBehavioral observations were conducted on a free-ranging bonobo group at Wamba in the Luo Scientific Reserve, Democratic Republic of the Congo. Periovulatory periods (POPs) were estimated from the timing of detumescence marking the end of the maximal swelling phase, following Ryu et al. (2022). For each male, we calculated the proportion of copulations with POP females. Using all-day focal follows targeting mature males, we tested for rank-related bias in their copulation rates and evaluated the effects of the party-level operational sex ratio (OSR; the ratio of mature males to sexually receptive females) on the focal males probability of copulation and intermale aggression. ResultsHigher-ranking males were more likely to copulate with POP females, yet males of all ranks engaged in copulation on most of focal observation days (twice per day, on average). Lower party-level OSR values increased the focal males probability of copulations while reducing intermale aggression. DiscussionProlonged sexual receptivity in female bonobos--yielding a pool of sexually receptive but non-POP females--may broaden male copulation opportunities beyond dominance rank and reduces intermale mating competition, even when POPs are detectable.

In human foraging societies, hunting skill is often interpreted as a signal of male quality linked to his reproductive success through his ability to provision his family and community. Similarly, in some bird and insect species, males offer their mates food to indicate their quality as a provider. Among non-human primates, however, the relationship between meat sharing and reproductive success is underexplored, leaving the evolutionary origins of this phenomenon unresolved. Guinea baboons (Papio papio) are a promising model to investigate whether meat sharing signals male quality, since females choose their mates, have been shown to rely on males to catch and share prey, and are responsive to male foraging skill. We combined records of 109 meat-eating events with nine years of behavioural data to test whether males who more frequently acquired and shared meat with females had more females in their social units for longer. Contrary to our predictions, we found no evidence that females preferred males who acquired or shared meat more frequently, suggesting that meat acquisition does not function as a signal of male quality in Guinea baboons. One explanation may be the relatively low frequency of meat-eating events. Another is that females are less dependent on males for meat than previously reported. Our results revealed that nearly half (41%) of female meat intake originated from sources other than her unit male, including the first documented cases of female prey capture (11% of events). Thus, females likely apply other, more pertinent, criteria in mate choice.

Allogrooming is fundamental to social relationships in many group-living mammals. In primates, allogrooming has been the subject of decades of research, and has been shown to play an essential role in maintaining social affiliations, and often interchanged for social tolerance and support. Yet, while the equivalent behaviour of allopreening occurs in many avian species, most description has been limited to its role in pair formation and maintenance, with little known about non-pair contexts. Here we investigated the decision-making associated with allopreening in wild sulphur-crested cockatoos, conducting detailed observations of 182 allopreening events between 126 individuals while concurrently recording rank, aggressive interactions, and social networks. We found no influence of sex as predicted if allopreening was primarily about pair bonding, but instead a positive correlation between allopreening and aggression (given and received). Within interactions, individuals were influenced by social association strength and rank, with individuals preening for longer and with more turn-taking when interacting with stronger social associates, and individuals investing more in interactions initiated by higher-ranked individuals. Our results are highly suggestive that allopreening may serve a convergent function in wild parrots to primates, both in maintaining social bonds and in negotiating social tolerance.

Communication allows organisms to quickly convey information vital for survival or fitness. Chemical communication and speed-accuracy trade-offs are ubiquitous in animal decision making. Most studies have used species which forage mainly above-ground species, tested in an epigean setting, but it remains unclear whether below-ground species behave similarly. Here, we use the below-ground ant Tetramorium alpestre to assess the efficacy of above- vs. below-ground mazes, the accuracy of decisions when using natural vs. artificial pheromones, the presence of a speed-accuracy trade-off, and the pheromones effect on aggression. Ants decided more quickly under below-ground than above-ground conditions, indicating they may be distracted by above-ground stimuli. Ants followed both natural and artificial trails but in direct competition preferred artificial trails, likely due to a higher pheromone concentration. Surprisingly, no speed-accuracy trade off was observed during path decision-making. Lastly, population origin but not pheromones affected if and how aggression occurred in presence of trail and home-range marking pheromones. We argue that the design of behavioural tests should match the lifestyle of the focal organism. We further speculate that speed-accuracy trade-offs likely are highly species- and context-specific and other factors besides chemicals seem important to trigger aggression, at least in this species.

Mixed-species groups are common in nature. Such groups are characterised by the presence of one or more majority species, and smaller numbers of minority species. Minority individuals are expected to be subject to oddity effects; by looking or behaving differently to majority members they should be disproportionately targeted by predators. Given this, why might minority species remain in mixed-species groups? To address this question, we used threespine sticklebacks (Gasterosteus aculeatus) as predators and two species of virtual prey presented via videos. We compared predator attacks on solitary prey, and odd and majority grouped prey individuals in groups of different sizes. We found that solitary prey were attacked significantly more than odd and majority grouped prey, while, in fact, odd and majority grouped prey did not differ from each other in terms of attacks received. We also found that prey in smaller groups suffered significantly more attacks than prey in larger groups. These findings provide no evidence for oddity effects but suggest evidence of a confusion effect. Natural mixed-species groups persist for various reasons, for example as foraging guilds, or because some members take advantage of more effective vigilance or alarm calls of others. We suggest, based on these findings, an additional non-mutually exclusive reason; under some circumstances, odd individuals might join larger heterospecific groups because any costs of being odd are greatly outweighed by the predation risk costs of remaining alone.

The assessment of current risk is essential in informing defensive behaviours. Many animals use cues left behind by predators, known as secondary predator cues (SPCs), to assess risk and respond appropriately. However, meerkats, Suricata suricatta, exhibit seemingly unique mobbing-like responses to these cues. The benefit of this high-intensity recruitment response is unclear, as unlike genuine mobbing, it cannot help to drive the predator away. One potential explanation is that mobbing-like responses promote information gathering and collective decision-making by the whole group. To examine this, we investigated (i) how meerkats responses to SPCs differ from mobbing live animals and (ii) the subsequent behavioural changes following a SPC encounter. Using a dataset gathered over a 20-year period, we first compared the rate of SPC recruitment versus the rate of animal mobbing. We then investigated changes in behaviour (alarm calling, sentinel bouts, distance travelled and pup provisioning) in the hour before and after a SPC encounter. Abiotic factors did not affect recruitment rate to SPCs or live animals, or influence the change in behavioural responses following a SPC encounter. The presence of pups reduced response rate to SPCs, but had no effect on animal mobbing rate, supporting experimental findings that responses towards SPCs are unlikely to function as a form of teaching. Alarm calling rate increased and the distance travelled by the group decreased following a SPC encounter, and were unaffected by the presence of pups or abiotic conditions. The results indicate group-level behavioural changes following a SPC encounter, and a greater degree of plasticity in recruitment to SPCs than to live animals. This response plasticity may reflect a context-dependent need to gather information to make collective decisions for defensive behaviour according to the level of threat perceived.

In social living animals, individuals typically use two main strategies to find food: either by exploiting social information (scrounger) or relying on personal knowledge (producer). These tactics are often linked to different life-history strategies. Access to foraging patches in hierarchical social groups may constrain the use of the producer-scrounger strategies, selecting for colour ornaments to act as status badges. In sexual dimorphic species, males and females may exhibit distinct life-history strategies, with females often lacking a clear badge-of-status and occupying subordinate roles. Here we address the question of how differences in social signalling and personality influence foraging behaviour and the individuals decision to play producer or scrounger, using males and females European serins, Serinus serinus. Specifically, we analysed how individual traits such as sex, plumage colouration, and boldness, relate with foraging strategies in both solitary and social contexts. In solitary contexts, colourful individuals, regardless of sex, were faster to find food, as were bolder males and shyer females. In social contexts, less colourful males and more colourful females adopted the producer strategy, while males foraging ability was influenced by their companions boldness. Our results reveal that personality and colour differences are linked to social foraging tactics in serins in a sex-dependent manner, highlighting the adaptive value of individual traits in both sexes, and their potential implications for social evolution.

The ability to anticipate periodically available resources is observed in several animals and improves performance in obtaining resources and adaptability. Spatio-temporal learning occurs when they associate the correct time and location of future events. We evaluate whether leaf-cutting ants Acromyrmex subterraneus can anticipate the presence of sucrose and examine potential anticipatory effects. Five colonies were used in an experimental setup where, from a central tray, two trails in opposite directions gave access to either the sucrose or to nothing. For 21 consecutive days sucrose was offered at the same place and the same time. Cameras recorded the flow of individuals at 4 different phases: before feeding (10h00-11h00), pre-feeding (11h30-12h00), feeding (12h00-13h00) and after feeding (14h00-15h00). On the 22nd day sugar was not supplied. On the 21st day the ants were marked and the next day, observed. Our results shows that: (1) the ants responded positively to the stimulus presented by forming the foraging trail to collect sucrose; (2) before feeding there was no significant difference in ant flow between the trails, but after feeding, the ant flow was consistently higher on trail that led to sucrose, which we called a keep going behavior; (3) there was a progressive spatio-temporal learning, given that ants began to appear earlier in pre-feeding throghout the weeks; (4) on the 22nd day, the ants presented themselves 10 minutes in advance and remained in the correct place; (5) the marked ants indicated that even without any resource the empty place continued to be explored. The colonies were able to learn where and when to look for food. Due to the adjustment of the ants to the stimuli of the environment it was possible to prepare for the collection of sucrose and the success in foraging for the colony. Summary statementLeaf-cutting ants are capable of spatio-temporal learning and this process has relevance on mass foraging recruitment and overall social organization of the colony.

Inter-individual recognition is crucial for stable social relationships and it is frequently mediated through vocal signatures. In socially complex species, recognition may additionally require additional levels corresponding to other layers of social organisation such as the pair, family, social group or colony. Additional vocal signatures may encode these different levels of social organisations for recognition. We investigated this hypothesis in the calls of the rook (Corvus frugilegus), a highly social corvid. Rooks form large breeding colonies where multiple pairs nest in clusters. We recorded the calls of five colonies located in France and in Great Britain, including both wild and captive colonies. To exclude variations due to different call types, we focused on the loud nest call produced exclusively by nesting females during the breeding season. We compared the acoustic distance of calls from each individual and between individuals at various levels of nest proximity, i.e. from the same nest cluster, from different nest clusters, from colonies within the same country, and from colonies in different countries. The only vocal signatures we found were at the individual level, but not at the nest cluster or colony level. This suggests a lack of vocal convergence in this species, at least for the nest call, which may be important for pair recognition in large colonies. Further studies should now evaluate if types of calls other than the nest call better carry vocal signatures as markers of different layers of sociality in this species, or if vocal divergence is a more general vocal phenomenon. In that case, applying new methods of monitoring vocal signatures in wild individuals should help understand the cognitive, social and environmental mechanisms underlying this vocal singularisation. 1. Significance statementInter-individual recognition is crucial for social relationships in animals, and is often mediated by individual-specific acoustic characteristics in vocalisations, called a vocal signature. High levels of social organisations, such as a social group of familiar conspecifics or a breeding colony, may likewise be signalled by vocal signatures shared by multiple individuals. We used machine-learning techniques to investigate vocal signatures at multiple social levels in the nest call of brooding female rooks, a corvid species that breeds colonially but lives year-round in social groups. We find evidence of a strong individual vocal signature, but no common vocal signature even in females that nest close together, or in the same colony. A strong individual vocal signature may be a potent tool to monitor populations in this species with minimal disturbance and minimal material, especially as corvids are frequently targeted by human-fauna conflicts in continental Europe.

Herring gulls are one of the few species that thrive in anthropogenic landscapes and their familiarity with people makes them an excellent target for studies of inter-species social cognition. Urban gulls pay attention to human behaviour in food-related contexts and we set out to investigate whether such cues can be used to redirect a gulls attention to potential food items in their environment. Herring gulls were given free choice of two differently coloured anthropogenic food items in the presence of a demonstrator, who was either sitting still or pretending to eat food from an item that matched one of the secondary food items. We found that a demonstrator mimicking eating significantly increased the likelihood of an approach or peck. Furthermore, 95% of pecks were directed towards the secondary food item which colour-matched the demonstrators food item. The results show situation-dependent attentional modulation in gulls, whereby gulls are able to use human cues for stimulus enhancement and foraging decisions. Given the relatively recent history of urbanisation in herring gulls, this cross-species social information transfer is likely to be a by-product of the cognitive flexibility inherent in kleptoparasitic species.

Wild carrion crows eavesdrop on human speech and respond more strongly to it than to the calls of pigeons or parakeets. However, it remains unclear whether this behaviour provides any benefit to them, and if so, under which environmental conditions such a benefit could be expected. I used an agent-based model to examine the effect of eavesdropping on the survival of a carrion crow under different environmental conditions. The crow could gain points from foraging, but also had to avoid encounters with a human in order to not lose points. In addition to eavesdropping, it could visually scan the patch for human presence and, once detected, could keep track of the humans location. I found that eavesdropping led to higher final scores and higher rates of survival than visual scanning alone if the human density on the patch was elevated, or if there were visual obstacles reducing the accuracy of visual scans. Such environmental conditions are particularly common for urban crows foraging in areas such as public parks. The model provides a proof of concept for future empirical research into the potentially differential survival of urban crows eavesdropping on speech.

Cooperative breeding is widely reported across the animal kingdom. In birds, it is hypothesised to be most common in altricial species (where chicks are dependent on parental care in the nest after hatching), with few described cases in precocial species (where chicks are more independent immediately after hatching). However, cooperative breeding may also be more difficult to detect in precocial species and therefore has been overlooked. In this study, we investigate whether vulturine guineafowl (Acryllium vulturinum)--which have precocial young--breed cooperatively and, if so, how care is distributed among group members. Using data collected from colour-banded individuals in one social group of vulturine guineafowl over three different breeding seasons, we found that multiple females can attempt to reproduce in the same breeding season. Broods had close adult associates, and most of these associates exhibited four distinct cooperative breeding behaviours: babysitting, within-group chick guarding, covering the chicks under the wings and calling the chicks to food. Further, we found that offspring care is significantly male-biased, that non-mother individuals provided most of the care each brood received, that breeding females differed in how much help they received, and that carers pay a foraging cost when providing care. Our results confirm that vulturine guineafowl are cooperative breeders, which they combine with an unusual plural-breeding social system. Our study also adds to growing evidence that cooperative breeding may be more widespread among species with precocial young than previously thought, thereby providing a counterpoint to the altriciality-cooperative breeding hypothesis.

Collective group decisions are important for the survival and reproduction of social mammals, with inter-individual interactions often driving group-level emergent behavior. Activity synchronization is an important collective behavior, with differences in nutritional requirements leading to foraging asynchrony. Individual variation between animals (such as sex or social relationships) are predicted to affect ungulate synchronization and spatial proximity, with between-sex differences consequently influencing sexual segregation evolution in ungulates. Although investigated independently, the relative roles of sex, sociality and proximity in synchronization are rarely investigated concurrently, especially in regards to affiliative relationships. Asynchrony influences fission-fusion dynamics and social segregation, but little is known how short-term changes in synchrony affects fission. Using a mixed-sex group of feral cattle (Bos taurus), we evaluated the supporting evidence for several predictions arising from the current understanding of synchronization in ungulates. We investigated if sex and social relationships (dominance and affiliation) affected foraging, behavioral synchrony and proximity. We also investigated whether group synchrony affected short-term changes in group size (fission events). We found that same-sex dyads were more likely to be synchronized than mixed-sex dyads, but differences in dominance and affiliation did not affect dyadic synchrony. Focal animals were more synchronized with closest neighbors than with another randomly selected conspecific. Reduction in group size was more likely when group synchrony was lower, highlighting the importance of asynchrony in temporary movement decisions. Inter-individual differences can explain variation in collective behavior, with synchronization being biased towards certain individuals by favoring animals in close spatial proximity and those of the same-sex. LAY SUMMARYIn ungulates, differences in energetic requirements lead to variation in activity, resulting in social and sexual segregation. However, sex, social relationships and spatial proximity are rarely investigated concurrently in relation to synchrony. We investigated synchronization and fission in a feral ungulate relative to individual differences in social relationship and proximity. Sex and proximity affected synchrony and fission events were more likely when synchrony was lower, highlighting the underlying processes in the evolution of sexual segregation.

The ability to stop behaviour is essential for adapting to changes in the environment, a principle that holds true across various species. While traditionally considered a unitary psychological construct, recent studies indicate that this ability is multifaceted. Our research evaluates this multifaceted nature using three tasks that measure stopping in different contexts in two related gull species: herring gulls (Larus argentatus) and lesser black-backed gulls (L. fuscus). These species were selected for their distinct migration and foraging strategies, offering a unique lens through which to examine behavioural adaptations. Across tasks and species, we conceptualised stopping as a race between a go and a stop runner, and predicted correlations based on the type of stop stimulus, the relative timing of the go and the stop stimuli, and the type of action that needed to be stopped. We found correlations between measures of going across tasks, but there was less consistency in measures of stopping. Furthermore, we observed significant differences in going and stopping behaviours that were specific to each species, which may be linked to their migration and foraging strategies. These findings highlight the importance of considering the multifaceted nature of stopping in evolutionary and behavioural studies.

Extractive foraging is generally studied from the perspective of behavioral flexibility, cognitive ability, innovation and social learning. Despite its potential to elucidate synanthropic adaptation in species exploiting enclosed anthropogenic food, research on extractive foraging under urban conditions is limited. Since a large extent of anthropogenic food is packaged and contains highly processed food, processes of identification/extraction of food by nonhuman species become intriguing themes of research. We studied how processing status of embedded food determined extraction decisions across groups of a species differing in exposure and familiarity to the food. Further, we tested the generalizability of extraction methods. Experimenting with wild bonnet macaques (Macaca radiata), we found exposure- and form (native/shelled/peeled)-specific familiarity to peanuts, state (raw/boiled/roasted)-specific distinction in depeeling, and exposure- and state-specific differences in methods of depeeling. Group with the highest exposure to peanut differed in its propensity to use sophisticated extraction methods, e.g. depeeling by rubbing between palms (bimanual asymmetric action) and rubbing against horizontal substrata (unimanual action). The innovative methods were also extended to roasted peas and chickpeas by the urban group. Our study establishes a causal relationship between familiarity and processing status of food and shows the generalized extension of extraction methods based on food categorization. Summary StatementNonhuman species in cities face upheaval challenges of accessing enclosed and highly processed anthropogenic food. We studied the effects of minor processing of enclosed food on its extraction decisions.