Exploring the evolutionary origins of overimitation: a comparison across domesticated and non-domesticated canids

Watched or not: Overimitation in dogs under different attentional states

Domestic dogs (Canis familiaris) have been documented to 'overimitate' humans - a form of social learning - by copying their causally-irrelevant actions. It is suggested that this behaviour results from social, affiliative motivations. Dogs have also been known to behave differently when they are being watched (or not) by humans, such as by following commands better (or worse). In this study, we tested whether dogs' copying behaviour would also be sensitive to their caregiver's attentional states. The subject's caregiver demonstrated irrelevant and relevant actions in the dot-touching overimitation task, then during trials the caregiver was either watching their dog or turned away. Our results revealed no difference in dogs' irrelevant-action copying; however, we found that dogs approached the dots less per trial when their caregiver was watching them. Dogs also copied their caregiver's leftward sliding of a door (to obtain a food reward) more accurately when they were being watched by their caregiver. Finally, dogs who copied the irrelevant action did so more often after obtaining their food reward, which supports that these dogs may have had two separate goals: a primary instrumental goal and a secondary social goal.

Dogs with prior experience of a task still overimitate their caregiver

Domestic dogs have been shown to copy their caregiver's actions, including ones which are causally-irrelevant to a physical goal-a behaviour called "overimitation". In a new overimitation task with a non-food reward, this study investigated "causal misunderstanding"-falsely assuming causally-irrelevant actions to have functional relevancy-as an explanation for dog overimitation (N = 81). By providing dogs with prior experience of the task to learn about the consequences of its irrelevant box-stepping and relevant bucket-opening action to obtain a toy-ball, we tested whether and when dogs would copy their caregiver's irrelevant-action demonstrations. Dogs with and without prior experience were compared to a third (control) group of dogs, who had neither prior experience nor caregiver demonstrations of the task. Results revealed that the timing of overimitation, rather than its frequency, was closely related to dogs' prior experience: dogs with prior experience attended to their reward first, then interacted with the irrelevant box later ("post-goal overimitation"), while dogs without prior experience first interacted with the irrelevant box ("pre-goal overimitation"). Our results suggest that, when action consequences are understood, dogs are overimitating for a secondary social goal that is clearly distinct from the task goal of obtaining a physical reward.

Socially priming dogs in an overimitation task

Overimitation - the copying of another's unnecessary or irrelevant actions toward a goal - is largely considered to be uniquely human. Recent studies, however, have found evidence of this behavior in dogs. Humans seem to overimitate more or less depending on social factors, such as the cultural origin of the demonstrator. Like humans, dogs may have social motivations behind their overimitation, since they have been shown to copy irrelevant actions more from their caregivers than from strangers. By using priming methodology, this study aimed to investigate whether dogs' overimitation can be facilitated via the experimental manipulation of their attachment-based motivations. To test this, we invited caregivers to demonstrate goal-irrelevant and relevant actions to their dog, following either a dog-caregiver relationship prime, a dog-caregiver attention prime, or no prime. Our results showed no significant main effect of priming on copying behavior for either relevant or irrelevant actions, but we found a trend that unprimed dogs copied the least actions overall. Additionally, dogs copied their caregiver's relevant actions more often and more faithfully as the number of trials increased. Our final finding was that dogs were much more likely to copy irrelevant actions after (rather than before) already achieving the goal. This study discusses the social motivations behind dog imitative behavior, and has potential methodological implications regarding the influence of priming on dog behavioral studies.

Does owner handedness influence paw preference in dogs?

Handedness has proven to be the most effective and least intrusive measure of laterality in many species. Several studies have investigated paw preference in dogs (Canis familiaris) without considering the potential impact that owner's handedness may have on it, despite dogs being a domesticated species. The aim of this study was to investigate whether owner handedness influences paw preference in their dogs. Sixty-two dogs had their paw preference tested using a Paw Task and a Reach Task in their home over 10 days, recorded by their owners. Interestingly, it was found that left-handed owners were more likely to own a dog with a left paw bias, and right-handed owners were more likely to own a dog with a right paw bias. In the Paw Task, the hand presented to a dog did not significantly predict which paw the dog lifted in response. Furthermore, it was found that females displayed a right paw bias at all age groups. However, males had a left paw bias in puppyhood and right paw bias in older age groups. We conclude that owner handedness influences paw preference in dogs, and it should be considered when suitably pairing dogs to potential owners, especially in assistance work.

Toward more equal and mutual human-pet relations: Insights and possible solutions based on social psychological theories

Human-pet relations are imbued with power imbalances, with many pets depending on humans for food and water, shelter, health care, and sheer survival. A majority of people report loving their pets and consider them to be integral family members; however, the care provided to pets varies widely and can be, in some cases, suboptimal. Yet, building more equal relations between humans and their pets could provide benefits to both parties. To achieve this increased equality and mutuality, the current paper proposes theory-based solutions. Specifically, and building on established social psychological theories, namely theories of intergroup relations and of human motivation, the current paper identifies both social and relational factors which, if socially and individually promoted, could trigger more equal and possibly mutually beneficial relationships with pets. We provide concrete examples illustrating how these factors can be maximized and promoted.

Overimitation in Dogs: Is There a Link to the Quality of the Relationship with the Caregiver?

Overimitation, the copying of causally irrelevant or non-functional actions, is well-known from humans but completely absent in other primates. Recent studies from our lab have provided evidence for overimitation in canines. Previously, we found that half of tested pet dogs copied their human caregiver's irrelevant action, while only few did so when the action was demonstrated by an unfamiliar experimenter. Therefore, we hypothesized that dogs show overimitation as a result of socio-motivational grounds. To test this more specifically, here we investigated how the relationship with the caregiver influenced the eagerness to overimitate. Given the high variability in the tendency to overimitate their caregiver, we hypothesized that not only familiarity but also relationship quality influences whether dogs faithfully copy their caregiver. For this purpose, on the one hand we measured the overimitation tendency (with the same test as in the two studies before) and on the other hand the relationship quality between the dogs and their caregivers. Although we found no significant correlation between the two test results, our data might suggest that, on average, dogs who overimitated seemed to show more referential and affiliative behaviours towards the owner than dogs who showed less or no copying of the irrelevant action. Notably, as a group, those dogs that showed the highest level of copying accuracy of the irrelevant action showed the highest level of gazing and synchronization towards the owner.

Expression unleashed: The evolutionary and cognitive foundations of human communication

Human expression is open-ended, versatile, and diverse, ranging from ordinary language use to painting, from exaggerated displays of affection to micro-movements that aid coordination. Here we present and defend the claim that this expressive diversity is united by an interrelated suite of cognitive capacities, the evolved functions of which are the expression and recognition of informative intentions. We describe how evolutionary dynamics normally leash communication to narrow domains of statistical mutual benefit, and how expression is unleashed in humans. The relevant cognitive capacities are cognitive adaptations to living in a partner choice social ecology; and they are, correspondingly, part of the ordinarily developing human cognitive phenotype, emerging early and reliably in ontogeny. In other words, we identify distinctive features of our species' social ecology to explain how and why humans, and only humans, evolved the cognitive capacities that, in turn, lead to massive diversity and open-endedness in means and modes of expression. Language use is but one of these modes of expression, albeit one of manifestly high importance. We make cross-species comparisons, describe how the relevant cognitive capacities can evolve in a gradual manner, and survey how unleashed expression facilitates not only language use, but also novel behaviour in many other domains too, focusing on the examples of joint action, teaching, punishment, and art, all of which are ubiquitous in human societies but relatively rare in other species. Much of this diversity derives from graded aspects of human expression, which can be used to satisfy informative intentions in creative and new ways. We aim to help reorient cognitive pragmatics, as a phenomenon that is not a supplement to linguistic communication and on the periphery of language science, but rather the foundation of the many of the most distinctive features of human behaviour, society, and culture.

Working Dog Training for the Twenty-First Century

Dogs are trained for a variety of working roles including assistance, protection, and detection work. Many canine working roles, in their modern iterations, were developed at the turn of the 20th century and training practices have since largely been passed down from trainer to trainer. In parallel, research in psychology has advanced our understanding of animal behavior, and specifically canine learning and cognition, over the last 20 years; however, this field has had little focus or practical impact on working dog training. The aims of this narrative review are to (1) orient the reader to key advances in animal behavior that we view as having important implications for working dog training, (2) highlight where such information is already implemented, and (3) indicate areas for future collaborative research bridging the gap between research and practice. Through a selective review of research on canine learning and behavior and training of working dogs, we hope to combine advances from scientists and practitioners to lead to better, more targeted, and functional research for working dogs.

Social learning from media: The need for a culturally diachronic developmental psychology

Since the proliferation of television sets into households began over half a century ago there has been widespread interest in the impact that viewing has on young children's development. Such interest has grown with the increasing availability of smart phones and tablets. In this review we examine the literature documenting human social learning and how this learning is impacted when the instructing agent appears on a screen instead of face-to-face. We then explore the shifting nature of screen-based media, with a focus on the increasingly socio-normative manner information is portrayed. We discuss how the changing nature of screen technology might be altering how children interpret what they see, and raise the possibility that this may render prevailing evidence as historical documentation, rather than setting out established developmental milestones that transcend the period in which they were documented. We contend that recognizing the significance of historically changing contexts in developmental psychology is timely when the COVID-19 climate is pushing data collection on-line for many labs, often using tasks that were developed primarily for face-to-face contexts.

How Dogs Perceive Humans and How Humans Should Treat Their Pet Dogs: Linking Cognition With Ethics

Humans interact with animals in numerous ways and on numerous levels. We are indeed living in an “animal”s world,’ in the sense that our lives are very much intertwined with the lives of animals. This also means that animals, like those dogs we commonly refer to as our pets, are living in a “human’s world” in the sense that it is us, not them, who, to a large degree, define and manage the interactions we have with them. In this sense, the human-animal relationship is nothing we should romanticize: it comes with clear power relations and thus with a set of responsibilities on the side of those who exercise this power. This holds, despite the fact that we like to think about our dogs as human’s best friend. Dogs have been part of human societies for longer than any other domestic species. Like no other species they exemplify the role of companion animals. Relationships with pet dogs are both very widespread and very intense, often leading to strong attachments between owners or caregivers and animals and to a treatment of these dogs as family members or even children. But how does this relationship look from the dogs’ perspective? How do they perceive the humans they engage with? What responsibilities and duties arise from the kind of mutual understanding, attachment, and the supposedly “special” bonds we form with them? Are there ethical implications, maybe even ethical implications beyond animal welfare? The past decades have seen an upsurge of research from comparative cognition on pet dogs’ cognitive and social skills, especially in comparison with and reference to humans. We will therefore set our discussion about the nature and ethical dimensions of the human–dog relationship against the background of the current empirical knowledge on dog (social) cognition. This allows us to analyze the human–dog relationship by applying an interdisciplinary approach that starts from the perspective of the dog to ultimately inform the perspective of humans. It is our aim to thereby identify ethical dimensions of the human–dog relationship that have been overlooked so far.

Selective overimitation in dogs

Dogs have not only shown different kinds of social learning, from either conspecifics or humans, including do-as-I-do imitation, deferred imitation, and selective imitation, but in two previous studies they have also shown an eagerness to copy causally irrelevant actions. This so-called overimitation is prevalent in humans but is totally absent in great apes. Whereas in one of two previous studies dogs copied actions from an experimenter (Johnston, Holden, & Santos in Developmental Science, 20, e12460, 2017), in the other a reasonable number of the dogs copied the irrelevant actions from their human caregiver (Huber, Popovová, Riener, Salobir, & Cimarelli in Learning & Behavior, 46, 387-397, 2018). Dogs have not only been domesticated to live and work with us, but many companion dogs develop strong affiliative relationships with their caregiver, which are akin to the attachment bonds between human children and their mother. We therefore assumed that overimitation in dogs might be strongly motivated by social factors, such as affiliation or conformity. To test this hypothesis, we confronted dogs with the same demonstration of causally relevant and irrelevant actions as in the previous study (Huber et al. in Learning & Behavior, 46, 387-397, 2018), but this time with an unfamiliar experimenter instead of the caregiver as the demonstrator. The results strongly supported our hypothesis: Whereas half of the subjects in the previous study replicated the causally irrelevant action demonstrated by their caregiver, only very few did so when the actions were demonstrated by the experimenter. We conclude that the eagerness of dogs to learn from humans and to copy even unnecessary actions is strongly facilitated by their relationship with the particular human.

Familiarity with humans affect dogs' tendencies to follow human majority groups

Recently, copying others’ behaviour has attracted attention among researchers. It aids individuals in reducing uncertainty about the knowledge of the environment and helps them in acquiring an adaptive behaviour at a lower cost than by learning it by themselves. Among the copying strategies, conformity, which is the copying of behavioural decisions presented by the majority, has been well studied and reported in many animals, including humans. The previous study showed that dogs did not conform to their multiple conspecific individuals; however, dogs have evolved to increase their adaptability while living with humans, and it is plausible that dogs have selected appropriate behaviour according to the behaviour of humans. Therefore, we investigated which factors influenced the choice of dogs in a situation where they have to choose one of two numerically unbalanced human groups. The results showed that the dogs followed the human majority group under certain conditions, depending on the familiarity with the human demonstrators. These results are important in considering the significance of groups for dogs and the factors of group formation, and will also provide a clue as to how dogs have penetrated into human society.

Coexistence of Diversified Dog Socialities and Territorialities in the City of Concepción, Chile

There has been scant research on the presence of stray dogs in cities. Studying their very considerable presence in Concepción (Chile) provided a unique opportunity to learn more about the different patterns of sociality and territoriality exhibited by the dog species. Via a set of case studies, we examined the behavior of urban dogs, adopting an ethnographic methodology. This yielded findings of the dogs' cognitive, social and spatial adjustment abilities, i.e., their territorialities. Our hypothesis was validated: We found numerous types of sociability, we confirmed the presence of two previously established categories: family dogs (pets, guard dogs and beggars' dogs) and stray dogs (dogs almost entirely unused to humans, aggressive dogs at the far end of the campus and feral dogs in the woods). We also identified three new ones: familiar stray dogs in packs (dogs both spatially and socially close to humans), pet-stray dogs (i.e., village dogs interacting closely with people) and free-roaming pet dogs. We conclude that an ongoing two-way bond between humans and animals allowed these dogs to became part of a city's urban identity and explains the stray dogs' plasticity in terms of adapting to the diversified urban habitat. We postulate that it was the human culture and range of urban areas in Concepción that gave rise to this unique diversity of sociospatial positioning and level of adjustment (e.g., dogs crossing crosswalks).

Genomic regions under selection in the feralization of the dingoes

Dingoes are wild canids living in Australia, originating from domestic dogs. They have lived isolated from both the wild and the domestic ancestor, making them a unique model for studying feralization. Here, we sequence the genomes of 10 dingoes and 2 New Guinea Singing Dogs. Phylogenetic and demographic analyses show that dingoes originate from dogs in southern East Asia, which migrated via Island Southeast Asia to reach Australia around 8300 years ago, and subsequently diverged into a genetically distinct population. Selection analysis identifies 50 positively selected genes enriched in digestion and metabolism, indicating a diet change during feralization of dingoes. Thirteen of these genes have shifted allele frequencies compared to dogs but not compared to wolves. Functional assays show that an A-to-G mutation in ARHGEF7 decreases the endogenous expression, suggesting behavioral adaptations related to the transitions in environment. Our results indicate that the feralization of the dingo induced positive selection on genomic regions correlated to neurodevelopment, metabolism and reproduction, in adaptation to a wild environment.

Human caregivers perceive racial bias in their pet dogs

Is there any empirical support for the popular stereotype that dogs are racist? As an initial inquiry into this question, we investigated whether human caregivers perceive racial bias in the behavior of their pet dogs. In 2 studies, caretakers completed explicit and implicit measures of racial preference and reported their dogs’ behavior toward White and Black people. White caretakers reported that their dogs displayed more positive behaviors toward White than Black people, and these reports of dog behaviors were significantly correlated with caretakers’ own explicit and implicit racial preferences. Increased interracial contact was associated with less reported pro-White dog behavior. Humans perceive racial biases in those around us, including our pets.

Persistence and conspecific observations improve problem-solving abilities of coyotes

Social learning has important ecological and evolutionary consequences but the role of certain factors, such as social rank, neophobia (i.e., avoidance of novel stimuli), persistence, and task-reward association, remain less understood. We examined the role of these factors in social learning by captive coyotes (Canis latrans) via three studies. Study 1 involved individual animals and eliminated object neophobia by familiarizing the subjects to the testing apparatus prior to testing. Studies 2 and 3 used mated pairs to assess social rank, and included object neophobia, but differed in that study 3 decoupled the food reward from the testing apparatus (i.e., altered task-reward association). For all three studies, we compared performance between coyotes that received a demonstration from a conspecific to control animals with no demonstration prior to testing. Coyotes displayed social learning during study 1; coyotes with a demonstrator were faster and more successful at solving the puzzle box but did not necessarily use the same modality as that observed to be successful. In study 2, there was no difference in success between treatment groups but this is likely because only one coyote within each pair was successful so successful coyote results were masked by their unsuccessful mate. In study 3, there was no difference in success between treatment groups; only two coyotes, both dominant, hand-reared males with demonstrators were able to perform the task. However, coyotes with a demonstrator were less neophobic, measured as latency to approach the object, and more persistent, measured as time spent working on the apparatus. Social rank was the best predictor of neophobia and persistence and was also retained in the best model for time to eat inside the apparatus, a post-trial measurement of object neophobia. These results suggest coyotes are capable of social learning for novel tasks but social rank, neophobia, and persistence influence their social-learning capabilities. This study contributes to understanding the mechanisms underlying how animals gain information about their environment.

Dogs do not demonstrate a human-like bias to defer to communicative cues

Human children and domesticated dogs learn from communicative cues, such as pointing, in highly similar ways. In two experiments, we investigate whether dogs are biased to defer to these cues in the same way as human children. We tested dogs on a cueing task similar to one previously conducted in human children. Dogs received conflicting information about the location of a treat from a Guesser and a Knower, who either used communicative cues (i.e., pointing; Experiments 1 and 2), non-communicative physical cues (i.e., a wooden marker; Experiment 1), or goal-directed actions (i.e., grasping; Experiment 2). Although human children tested previously struggled to override inaccurate information provided by the Guesser when she used communicative cues, in contrast to physical cues or goal-directed actions, dogs were more likely to override the Guesser's information when she used communicative cues or goal-directed actions than when she used non-communicative physical cues. Given that dogs did not show the same selective bias towards the Guesser's information in communicative contexts, these findings provide clear evidence that dogs do not demonstrate a human-like bias to defer to communicative cues. Instead, dogs may be more likely to critically evaluate information presented via communicative cues than either physical or non-communicative cues.

Would dogs copy irrelevant actions from their human caregiver?

Companion dogs learn easily from humans, including human behavior, human communication, and some aspects of the human-made environment. They benefit from having the opportunity to learn from humans and are able to spontaneously synchronize their behavior with that of their caregiver. Here, we tested whether pet dogs would show a special form of observational learning, one that has been considered uniquely human. Indeed, humans show overimitation, the faithful copying of causally irrelevant actions, but great apes do not. Because in humans this peculiar form of imitation is strongly motivated by social factors, such as affiliation or conformity, we hypothesized that domesticated and enculturated dogs are more likely than apes are to copy such actions, especially if shown by their affiliated caregiver. Indeed, half of the dogs replicated a causally irrelevant action that was demonstrated by their caregiver, and about the same number did this whether they saw only this action being demonstrated or being demonstrated before or after a causally relevant, functional action. The demonstration of a causally relevant action, one that is immediately followed by access to food, thus does not inhibit the copying of an action that is spatially separated and functionally opaque. Given that the copying frequency in this study was low overall, these results suggest evidence for overimitation in dogs, which might challenge the human uniqueness of this type of social learning.

In what sense are dogs special? Canine cognition in comparative context

The great increase in the study of dog cognition in the current century has yielded insights into canine cognition in a variety of domains. In this review, we seek to place our enhanced understanding of canine cognition into context. We argue that in order to assess dog cognition, we need to regard dogs from three different perspectives: phylogenetically, as carnivoran and specifically a canid; ecologically, as social, cursorial hunters; and anthropogenically, as a domestic animal. A principled understanding of canine cognition should therefore involve comparing dogs' cognition with that of other carnivorans, other social hunters, and other domestic animals. This paper contrasts dog cognition with what is known about cognition in species that fit into these three categories, with a particular emphasis on wolves, cats, spotted hyenas, chimpanzees, dolphins, horses, and pigeons. We cover sensory cognition, physical cognition, spatial cognition, social cognition, and self-awareness. Although the comparisons are incomplete, because of the limited range of studies of some of the other relevant species, we conclude that dog cognition is influenced by the membership of all three of these groups, and taking all three groups into account, dog cognition does not look exceptional.

The Rationality of (Over)imitation

Imitation is a powerful and ubiquitous social learning strategy, fundamental for the development of individual skills and cultural traditions. Recent research on the cognitive foundations and development of imitation, though, presents a surprising picture: Although even infants imitate in selective, efficient, and rational ways, children and adults engage in overimitation. Rather than imitating selectively and efficiently, they sometimes faithfully reproduce causally irrelevant actions as much as relevant ones. In this article, we suggest a new perspective on this phenomenon by integrating established findings on children’s more general capacities for rational action parsing with newer findings on overimitation. We suggest that overimitation is a consequence of children’s growing capacities to understand causal and social constraints in relation to goals and that it rests on the human capacity to represent observed actions simultaneously on different levels of goal hierarchies.

What is unique about shared reality? Insights from a new comparison species

We introduce a new comparison species-domesticated dogs (Canis familaris)-that can shed light on the evolutionary origins of shared reality. Given that dogs share many basic building blocks of shared reality (e.g. representing others' perceptions, emotions, and behaviors) they provide an ideal species for pinpointing unique aspects of shared reality in humans. In particular, current research with dogs underscores two aspects of shared reality that may be special to humans. First, humans may be unique in our tendency to share reality involuntarily. Second, humans may be unique in the extent to which we share reality. Although both humans and dogs share reality in one-on-one interactions, only humans share reality at the more extensive group and cultural level.