Scholars@Duke
Brian Hare

Brian Hare

Professor of Evolutionary Anthropology
Evolutionary Anthropology
b.hare@duke.edu
Duke Box 90383, Durham, NC 27708-0383
004 Bio Sci Bldg, Durham, NC 27708

Selected Publications

In Response.

Journal Article Anesth Analg · June 6, 2024 Full text Link to item Cite

Response to Hansen Wheat et al.: Additional analysis further supports the early emergence of cooperative communication in dogs compared to wolves raised with more human exposure.

Journal Article Learning & behavior · June 2023 Here, we address Hansen Wheat et al.'s commentary in this journal in response to Salomons et al. Current Biology, 31(14), 3137-3144.E11, (2021). We conduct additional analyses in response to Hansen Wheat et al.'s two main questions. First, we examine the c ... Full text Cite

The Early Expression of Blatant Dehumanization in Children and Its Association with Outgroup Negativity.

Journal Article Human nature (Hawthorne, N.Y.) · June 2022 Dehumanization is observed in adults across cultures and is thought to motivate human violence. The age of its first expression remains largely untested. This research demonstrates that diverse representations of humanness, including a novel one, readily e ... Full text Open Access Cite

Total energy expenditure of bottlenose dolphins (Tursiops truncatus) of different ages.

Journal Article The Journal of experimental biology · July 6, 2021 Marine mammals are thought to have an energetically expensive lifestyle because endothermy is costly in marine environments. However, measurements of total energy expenditure (TEE; kcal/day) are available only for a limited number of marine mammals, becaus ... Full text Cite

Cooperative Communication with Humans Evolved to Emerge Early in Domestic Dogs.

Journal Article Current biology : CB · July 2021 Although we know that dogs evolved from wolves, it remains unclear how domestication affected dog cognition. One hypothesis suggests dog domestication altered social maturation by a process of selecting for an attraction to humans.1-3 Under this ... Full text Cite

Evolution of water conservation in humans.

Journal Article Current biology : CB · April 2021 To sustain life, humans and other terrestrial animals must maintain a tight balance of water gain and water loss each day.1-3 However, the evolution of human water balance physiology is poorly understood due to the absence of comparative measure ... Full text Cite

Dog cognitive development: a longitudinal study across the first 2 years of life.

Journal Article Animal cognition · March 2021 While our understanding of adult dog cognition has grown considerably over the past 20 years, relatively little is known about the ontogeny of dog cognition. To assess the development and longitudinal stability of cognitive traits in dogs, we administered ... Full text Cite

Is cognition the secret to working dog success?

Journal Article Animal cognition · March 2021 Dogs' special relationship with humans not only makes them ubiquitous in our lives, but working dogs specifically perform essential functions for us such as sniffing out bombs and pulling wheelchairs for the disabled. To enhance the performance of working ... Full text Cite

Assessing conservation attitudes and behaviors of Congolese children neighboring the world's first bonobo (Pan paniscus) release site.

Journal Article American journal of primatology · January 2021 Featured Publication Poaching and habitat destruction in the Congo Basin threaten African great apes including the bonobo (Pan paniscus), chimpanzees (Pan troglodytes), and gorillas (Gorilla spp.) with extinction. One way to combat extinction is to reintroduce rescued and reha ... Full text Cite

The Darwinian Road to Morality

Chapter · January 1, 2021 Full text Cite

Breed Differences in Dog Cognition Associated with Brain-Expressed Genes and Neurological Functions.

Journal Article Integrative and comparative biology · October 2020 Featured Publication Given their remarkable phenotypic diversity, dogs present a unique opportunity for investigating the genetic bases of cognitive and behavioral traits. Our previous work demonstrated that genetic relatedness among breeds accounts for a substantial portion o ... Full text Cite

Estimating the heritability of cognitive traits across dog breeds reveals highly heritable inhibitory control and communication factors.

Journal Article Animal cognition · September 2020 Featured Publication Trait heritability is necessary for evolution by both natural and artificial selection, yet we know little about the heritability of cognitive traits. Domestic dogs are a valuable study system for questions regarding the evolution of phenotypic diversity d ... Full text Cite

Cognitive characteristics of 8- to 10-week-old assistance dog puppies

Journal Article Animal Behaviour · August 1, 2020 Featured Publication To characterize the early ontogeny of dog cognition, we tested 168 domestic dog, Canis familiaris, puppies (97 females, 71 males; mean age = 9.2 weeks) in a novel test battery based on previous tasks developed and employed with adolescent and adult dogs. O ... Full text Cite

Age influences domestic dog cognitive performance independent of average breed lifespan.

Journal Article Animal cognition · July 2020 Across mammals, increased body size is positively associated with lifespan. However, within species, this relationship is inverted. This is well illustrated in dogs (Canis familiaris), where larger dogs exhibit accelerated life trajectories: growing faster ... Full text Cite

Do dog breeds differ in pain sensitivity? Veterinarians and the public believe they do.

Journal Article PloS one · January 2020 Humans do not respond to the pain of all humans equally; physical appearance and associated group identity affect how people respond to the pain of others. Here we ask if a similar differential response occurs when humans evaluate different individuals of ... Full text Cite

Coyotes living near cities are bolder: Implications for dog evolution and human-wildlife conflict

Journal Article Behaviour · January 1, 2020 How animal populations adapt to human modified landscapes is central to understanding modern behavioural evolution and improving wildlife management. Coyotes (Canis latrans) have adapted to human activities and thrive in both rural and urban areas. Bolder ... Full text Cite

Uncanny valley of the apes

Chapter · December 12, 2019 Humans have a complex emotional relationship with the other members of our great apes family. Great apes are appealing because of the close resemblances we share, but these resemblances can cause feelings of aversion and disgust. We propose that these feel ... Cite

Absolute brain size predicts dog breed differences in executive function.

Journal Article Animal cognition · March 2019 Large-scale phylogenetic studies of animal cognition have revealed robust links between absolute brain volume and species differences in executive function. However, past comparative samples have been composed largely of primates, which are characterized b ... Full text Cite

Prosociality and a Sociosexual Hypothesis for the Evolution of Same-Sex Attraction in Humans.

Journal Article Frontiers in psychology · January 2019 Human same-sex sexual attraction (SSSA) has long been considered to be an evolutionary puzzle. The trait is clearly biological: it is widespread and has a strong additive genetic basis, but how SSSA has evolved remains a subject of debate. Of itself, homos ... Full text Cite

Chimpanzee and bonobo

Chapter · January 1, 2019 Chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) are both our evolutionary closest living relatives. Human and Pan lineages diverged around 7 million years ago, and the chimpanzee and the bonobo branched 1-2 million years ago. Accordingly, the two ... Full text Cite

Chimpanzee and Bonobo

Chapter · January 1, 2019 Chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) are both our evolutionary closest living relatives. Human and Pan lineages diverged around 7 million years ago, and the chimpanzee and the bonobo branched 1–2 million years ago. Accordingly, the two ... Full text Cite

The development and flexibility of gaze alternations in bonobos and chimpanzees.

Journal Article Developmental science · July 2018 Infants' early gaze alternations are one of their first steps towards a sophisticated understanding of the social world. This ability, to gaze alternate between an object of interest and another individual also attending to that object, has been considered ... Full text Cite

Domestication experiments reveal developmental link between friendliness and cognition

Journal Article Journal of Bioeconomics · April 1, 2018 The goal of economics is to understand human preferences. Most research focuses on adult humans and does not take an evolutionary approach. In biology experimental evolution has been able to shift the preferences of animals. As an example, artificial selec ... Full text Cite

Bonobos Prefer Individuals that Hinder Others over Those that Help.

Journal Article Current biology : CB · January 2018 Humans closely monitor others' cooperative relationships [1, 2]. Children and adults willingly incur costs to reward helpers and punish non-helpers-even as bystanders [3-5]. Already by 3 months, infants favor individuals that they observe helping others [6 ... Full text Cite

Minding the bonobo mind

Chapter · January 1, 2018 In this chapter we introduce the central role the bonobo plays in testing evolutionary hypotheses regarding ape minds (including our own). The importance of bonobos has become apparent only recently with sustained fieldwork at multiple sites in the Congo B ... Full text Cite

Does the bonobo have a (chimpanzee-like) theory of mind?

Chapter · January 1, 2018 Theory of mind-the ability to reason about the thoughts and emotions of others-is central to what makes us human. Chimpanzees too appear to understand some psychological states. While less is known about bonobos, several lines of evidence suggest that the ... Full text Cite

Prosociality among non-kin in bonobos and chimpanzees compared

Chapter · January 1, 2018 Models of the origin of human prosociality towards non-kin have been primarily developed from chimpanzee studies. Substantially less effort has been made to consider the prosociality of bonobos. Like chimpanzees, bonobos cooperate with non-kin extensively ... Full text Cite

Bonobos: Unique in mind, brain, and behavior

Book · January 1, 2018 During the past decade there has been an explosion of scientific interest in the bonobo (Pan paniscus). This research has revealed exactly how unique bonobos are in their minds, brains and behavior. This book makes clear the central role that bonobos play ... Full text Cite

Bonobo population dynamics: Past patterns and future predictions for the Lola ya Bonobo population using demographic modelling

Chapter · January 1, 2018 Wildlife sanctuaries rescue, rehabilitate, reintroduce and provide life-long care for orphaned and injured animals. Understanding a sanctuary’s population dynamics—patterns in arrival, mortality and projected changes in population size—allows careful plann ... Full text Cite

Bonobo baby dominance: Did female defense of offspring lead to reduced male aggression?

Chapter · January 1, 2018 The dominance style of bonobos presents an evolutionary puzzle. Bonobos are not male dominant but female bonobos do not show traits typical of female-dominant species. This chapter proposes the offspring dominance hypothesis (ODH) as a potential solution. ... Full text Cite

Cognitive comparisons of genus Pan support bonobo self-domestication

Chapter · January 1, 2018 The self-domestication hypothesis (SDH) suggests bonobo psychology evolved due to selection against aggression and in favour of prosociality. This hypothesis was formulated based on similarities between bonobos and domesticated animals. This chapter review ... Full text Cite

Enhanced Selection of Assistance and Explosive Detection Dogs Using Cognitive Measures.

Journal Article Frontiers in veterinary science · January 2018 Working dogs play a variety of important roles, ranging from assisting individuals with disabilities, to explosive and medical detection work. Despite widespread demand, only a subset of dogs bred and trained for these roles ultimately succeed, creating a ... Full text Cite

Bonobos respond prosocially toward members of other groups.

Journal Article Scientific reports · November 2017 Modern humans live in an "exploded" network with unusually large circles of trust that form due to prosociality toward unfamiliar people (i.e. xenophilia). In a set of experiments we demonstrate that semi-free ranging bonobos (Pan paniscus) - both juvenile ... Full text Cite

Individual differences in cooperative communicative skills are more similar between dogs and humans than chimpanzees

Journal Article Animal Behaviour · April 1, 2017 By 2.5 years of age humans are more skilful than other apes on a set of social, but not nonsocial, cognitive tasks. Individual differences in human infants, but not chimpanzees, Pan troglodytes, are also explained by correlated variance in these cooperativ ... Full text Cite

Survival of the Friendliest: Homo sapiens Evolved via Selection for Prosociality.

Journal Article Annual review of psychology · January 2017 The challenge of studying human cognitive evolution is identifying unique features of our intelligence while explaining the processes by which they arose. Comparisons with nonhuman apes point to our early-emerging cooperative-communicative abilities as cru ... Full text Cite

No evidence for contagious yawning in lemurs.

Journal Article Animal cognition · September 2016 Among some haplorhine primates, including humans, relaxed yawns spread contagiously. Such contagious yawning has been linked to social bonds and empathy in some species. However, no studies have investigated contagious yawning in strepsirhines. We conducte ... Full text Cite

Metabolic acceleration and the evolution of human brain size and life history.

Journal Article Nature · May 2016 Humans are distinguished from the other living apes in having larger brains and an unusual life history that combines high reproductive output with slow childhood growth and exceptional longevity. This suite of derived traits suggests major changes in ener ... Full text Cite

Reward currency modulates human risk preferences

Journal Article Evolution and Human Behavior · March 1, 2016 Monetary and biological rewards differ in many ways. Yet studies of human decision-making typically involve money, whereas nonhuman studies involve food. We therefore examined how context shifts human risk preferences to illuminate the evolution of decisio ... Full text Cite

What's in a frame? Response to Kanngiesser & Woike (2016).

Journal Article Biology letters · January 2016 Full text Cite

Citizen Science as a New Tool in Dog Cognition Research

Journal Article PLoS ONE · September 16, 2015 Family dogs and dog owners offer a potentially powerful way to conduct citizen science to answer questions about animal behavior that are difficult to answer with more conventional approaches. Here we evaluate the quality of the first data on dog cognit ... Full text Open Access Link to item Cite

Social inhibitory control in five lemur species.

Journal Article Primates; journal of primatology · July 2015 We tested five lemur species-ring-tailed lemurs, ruffed lemurs, mongoose lemurs, black lemurs, and Coquerel's sifakas-(N = 52) in an experiment that evaluated skills for inhibitory control in a social context. First, two human experimenters presented ident ... Full text Cite

Evolution. Dogs hijack the human bonding pathway.

Journal Article Science (New York, N.Y.) · April 2015 Full text Cite

Moving bonobos off the scientifically endangered list

Journal Article Behaviour · February 10, 2015 This Special Issue of Behaviour includes twelve novel empirical papers focusing on the behaviour and cognition of both captive and wild bonobos (Pan paniscus). As our species less known closest relative, the bonobo has gone from being little studied to inc ... Full text Cite

Preference or paradigm? Bonobos show no evidence of other-regard in the standard prosocial choice task

Journal Article Behaviour · February 10, 2015 Bonobos are the only ape species, other than humans, that have demonstrated prosocial behaviors toward groupmates and strangers. However, bonobos have not been tested in the most frequently used test of prosociality in animals. The current study tested the ... Full text Cite

Experimental evidence that grooming and play are social currency in bonobos and chimpanzees

Journal Article Behaviour · February 10, 2015 While natural observations show apes use grooming and play as social currency, no experimental manipulations have been carried out to measure the effects of these behaviours on relationship formation in apes. While previous experiments have demonstrated ap ... Full text Cite

Bonobos and chimpanzees exploit helpful but not prohibitive gestures

Journal Article Behaviour · February 10, 2015 Previous research has shown that chimpanzees exploit the behavior of humans and conspecifics more readily in a competitive than a cooperative context. However, it is unknown whether bonobos, who outperform chimpanzees in some cooperative tasks, also show g ... Full text Cite

Bonobos and chimpanzees exhibit human-like framing effects.

Journal Article Biology letters · February 2015 Humans exhibit framing effects when making choices, appraising decisions involving losses differently from those involving gains. To directly test for the evolutionary origin of this bias, we examined decision-making in humans' closest living relatives: bo ... Full text Cite

Dogs (Canis familiaris) account for body orientation but not visual barriers when responding to pointing gestures.

Journal Article Journal of comparative psychology (Washington, D.C. : 1983) · August 2014 In a series of four experiments we investigated whether dogs use information about a human's visual perspective when responding to pointing gestures. While there is evidence that dogs may know what humans can and cannot see, and that they flexibly use huma ... Full text Cite

The ecology of spatial memory in four lemur species.

Journal Article Animal cognition · July 2014 Evolutionary theories suggest that ecology is a major factor shaping cognition in primates. However, there have been few systematic tests of spatial memory abilities involving multiple primate species. Here, we examine spatial memory skills in four strepsi ... Full text Cite

The evolution of self-control.

Journal Article Proc Natl Acad Sci U S A · May 20, 2014 Cognition presents evolutionary research with one of its greatest challenges. Cognitive evolution has been explained at the proximate level by shifts in absolute and relative brain volume and at the ultimate level by differences in social and dietary compl ... Full text Link to item Cite

Ring-tailed lemurs (Lemur catta) exploit information about what others can see but not what they can hear.

Journal Article Animal cognition · May 2014 Studies suggest that haplorhine primates are sensitive to what others can see and hear. Using two experimental designs, we tested the hypothesis that ring-tailed lemurs (N = 16) are also sensitive to the visual and auditory perception of others. In the fir ... Full text Cite

Differences in the early cognitive development of children and great apes.

Journal Article Developmental psychobiology · April 2014 There is very little research comparing great ape and human cognition developmentally. In the current studies we compared a cross-sectional sample of 2- to 4-year-old human children (n=48) with a large sample of chimpanzees and bonobos in the same age rang ... Full text Open Access Cite

Context specificity of inhibitory control in dogs.

Journal Article Animal cognition · January 2014 Across three experiments, we explored whether a dog's capacity for inhibitory control is stable or variable across decision-making contexts. In the social task, dogs were first exposed to the reputations of a stingy experimenter that never shared food and ... Full text Cite

Primate energy expenditure and life history.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · January 2014 Humans and other primates are distinct among placental mammals in having exceptionally slow rates of growth, reproduction, and aging. Primates' slow life history schedules are generally thought to reflect an evolved strategy of allocating energy away from ... Full text Cite

Craniofacial feminization, social tolerance, and the origins of behavioral modernity

Journal Article Current Anthropology · January 1, 2014 The past 200,000 years of human cultural evolution have witnessed the persistent establishment of behaviors involving innovation, planning depth, and abstract and symbolic thought, or what has been called "behavioral modernity." Demographic models based on ... Full text Cite

Spontaneous triadic engagement in bonobos (Pan paniscus) and chimpanzees (Pan troglodytes).

Journal Article Journal of comparative psychology (Washington, D.C. : 1983) · August 2013 Humans are believed to have evolved a unique motivation to participate in joint activities that first develops during infancy and supports the development of shared intentionality. We conducted five experiments with bonobos (Pan paniscus) and chimpanzees ( ... Full text Cite

Different ontogenetic patterns of testosterone production reflect divergent male reproductive strategies in chimpanzees and bonobos.

Journal Article Physiology & behavior · May 2013 Male reproductive effort is often strongly related to levels of the steroid hormone testosterone. However, little research has examined whether levels of testosterone throughout development might be tied to individual or species differences in the reproduc ... Full text Cite

Direct and indirect reputation formation in nonhuman great apes (Pan paniscus, Pan troglodytes, Gorilla gorilla, Pongo pygmaeus) and human children (Homo sapiens).

Journal Article Journal of comparative psychology (Washington, D.C. : 1983) · February 2013 Humans make decisions about when and with whom to cooperate based on their reputations. People either learn about others by direct interaction or by observing third-party interactions or gossip. An important question is whether other animal species, especi ... Full text Open Access Cite

Bonobos share with strangers.

Journal Article PloS one · January 2013 Humans are thought to possess a unique proclivity to share with others--including strangers. This puzzling phenomenon has led many to suggest that sharing with strangers originates from human-unique language, social norms, warfare and/or cooperative breedi ... Full text Cite

Animal behavior. For $60, a peek inside your dog's mind.

Journal Article Science (New York, N.Y.) · January 2013 Full text Cite

Context specificity of inhibitory control in dogs

Journal Article Animal Cognition · 2013 Cite

Chimpanzees and bonobos exhibit emotional responses to decision outcomes.

Journal Article PloS one · January 2013 The interface between cognition, emotion, and motivation is thought to be of central importance in understanding complex cognitive functions such as decision-making and executive control in humans. Although nonhuman apes have complex repertoires of emotion ... Full text Cite

Group Size Predicts Social but Not Nonsocial Cognition in Lemurs.

Journal Article PloS one · January 2013 The social intelligence hypothesis suggests that living in large social networks was the primary selective pressure for the evolution of complex cognition in primates. This hypothesis is supported by comparative studies demonstrating a positive relationshi ... Full text Cite

Pathogen flow: what we need to know.

Journal Article American journal of primatology · December 2012 Full text Cite

Chimpanzees and bonobos exhibit divergent spatial memory development.

Journal Article Developmental science · November 2012 Spatial cognition and memory are critical cognitive skills underlying foraging behaviors for all primates. While the emergence of these skills has been the focus of much research on human children, little is known about ontogenetic patterns shaping spatial ... Full text Open Access Cite

Decision making across social contexts: Competition increases preferences for risk in chimpanzees and bonobos

Journal Article Animal Behaviour · October 1, 2012 Context can have a powerful influence on decision-making strategies in humans. In particular, people sometimes shift their economic preferences depending on the broader social context, such as the presence of potential competitors or mating partners. Despi ... Full text Open Access Cite

Primate Neuroethology

Chapter · August 16, 2012 This edited volume is the first of its kind to bridge the epistemological gap between primate ethologists and primate neurobiologists. ... Open Access Cite

How does cognition evolve? Phylogenetic comparative psychology.

Journal Article Anim Cogn · March 2012 Now more than ever animal studies have the potential to test hypotheses regarding how cognition evolves. Comparative psychologists have developed new techniques to probe the cognitive mechanisms underlying animal behavior, and they have become increasingly ... Full text Open Access Link to item Cite

The self-domestication hypothesis: Evolution of bonobo psychology is due to selection against aggression

Journal Article Animal Behaviour · March 1, 2012 Experiments indicate that selection against aggression in mammals can have multiple effects on their morphology, physiology, behaviour and psychology, and that these results resemble a syndrome of changes observed in domestic animals. We hypothesize that s ... Full text Cite

Bonobos and chimpanzees infer the target of another's attention

Journal Article Animal Behaviour · February 1, 2012 We examined the ability of bonobos, Pan paniscus (N= 39), and chimpanzees, Pan troglodytes (N= 74), to infer the target of an experimenter's visual attention in a series of three experiments. In each experiment subjects were first introduced to a novel obj ... Full text Cite

A comparison of temperament in nonhuman apes and human infants.

Journal Article Developmental science · November 2011 The adaptive behavior of primates, including humans, is often mediated by temperament. Human behavior likely differs from that of other primates in part due to temperament. In the current study we compared the reaction of bonobos, chimpanzees, orangutans, ... Full text Open Access Cite

From hominoid to hominid mind: What changed and why?

Journal Article Annual Review of Anthropology · October 6, 2011 The living great apes, and in particular members of the genus Pan, help test hypotheses regarding the cognitive skills of our extinct common ancestor. Research with chimpanzees suggests that we share some but not all of our abilities to model another's per ... Full text Cite

Evidence from four lemur species that ringtailed lemur social cognition converges with that of haplorhine primates

Journal Article Animal Behaviour · May 1, 2011 Many haplorhine primates flexibly exploit social cues when competing for food. Whether strepsirrhine primates possess similar abilities is unknown. To explore the phylogenetic origins of such skills among primates, we tested ringtailed lemurs, Lemur catta, ... Full text Cite

Bonobo but not chimpanzee infants use socio-sexual contact with peers.

Journal Article Primates; journal of primatology · April 2011 Bonobos have been observed to use socio-sexual behavior at higher frequency than chimpanzees. Little is known about the developmental influences that shape this behavior in bonobos. We compared the social sexual behavior of wild-born bonobo (n = 8) and chi ... Full text Cite

Chimpanzees and bonobos distinguish between risk and ambiguity.

Journal Article Biology letters · February 2011 Although recent research has investigated animal decision-making under risk, little is known about how animals choose under conditions of ambiguity when they lack information about the available alternatives. Many models of choice behaviour assume that amb ... Full text Open Access Cite

Use of "entertainment" chimpanzees in commercials distorts public perception regarding their conservation status.

Journal Article PloS one · January 2011 Chimpanzees (Pan troglodytes) are often used in movies, commercials and print advertisements with the intention of eliciting a humorous response from audiences. The portrayal of chimpanzees in unnatural, human-like situations may have a negative effect on ... Full text Open Access Cite

Psychological health of orphan bonobos and chimpanzees in African sanctuaries.

Journal Article PloS one · January 2011 BackgroundFacilities across Africa care for apes orphaned by the trade for "bushmeat." These facilities, called sanctuaries, provide housing for apes such as bonobos (Pan paniscus) and chimpanzees (Pan troglodytes) who have been illegally taken fr ... Full text Cite

Differences in the cognitive skills of bonobos and chimpanzees.

Journal Article PloS one · August 2010 While bonobos and chimpanzees are both genetically and behaviorally very similar, they also differ in significant ways. Bonobos are more cautious and socially tolerant while chimpanzees are more dependent on extractive foraging, which requires tools. The s ... Full text Open Access Cite

Differential changes in steroid hormones before competition in bonobos and chimpanzees.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 2010 A large body of research has demonstrated that variation in competitive behavior across species and individuals is linked to variation in physiology. In particular, rapid changes in testosterone and cortisol during competition differ according to an indivi ... Full text Cite

Bonobos voluntarily share their own food with others.

Journal Article Current biology : CB · March 2010 Comparisons between chimpanzees and humans have led to the hypothesis that only humans voluntarily share their own food with others. However, it is hard to draw conclusions because the food-sharing preferences of our more tolerant relative, the bonobo (Pan ... Full text Cite

Reaching around barriers: the performance of the great apes and 3-5-year-old children.

Journal Article Animal cognition · March 2010 Inhibitory control has been suggested as a key predictive measure of problem-solving skills in human and nonhuman animals. However, there has yet to be a direct comparison of the inhibitory skills of the nonhuman apes and their development in human childre ... Full text Cite

Primate Social Cognition: Thirty Years After Premack and Woodruff

Chapter · February 1, 2010 This chapter addresses two aspects of primate social cognition-understanding of intentional, goal-directed action, and understanding perceptions, knowledge, and beliefs-focusing on the newest comparative research since the last major reviews were written o ... Full text Cite

Bonobos exhibit delayed development of social behavior and cognition relative to chimpanzees.

Journal Article Current biology : CB · February 2010 Phenotypic changes between species can occur when evolution shapes development. Here, we tested whether differences in the social behavior and cognition of bonobos and chimpanzees derive from shifts in their ontogeny, looking at behaviors pertaining to fee ... Full text Cite

Social Cognition: From Behavior-Reading to Mind-Reading

Chapter · January 1, 2010 Primates must navigate complex social landscapes in their daily lives: gathering information from and about others, competing with others for rewards like food and mates, and cooperating to obtain rewards as well. Although many species may exhibit similar ... Full text Cite

The structure of individual differences in the cognitive abilities of children and chimpanzees.

Journal Article Psychological science · January 2010 Most studies of animal cognition focus on group performance and neglect individual differences and the correlational structure of cognitive abilities. Moreover, no previous studies have compared the correlational structure of cognitive abilities in nonhuma ... Full text Cite

Chimpanzees coordinate in a negotiation game

Journal Article Evolution and Human Behavior · November 1, 2009 A crucially important aspect of human cooperation is the ability to negotiate to cooperative outcomes when interests over resources conflict. Although chimpanzees and other social species may negotiate conflicting interests regarding travel direction or ac ... Full text Cite

Breed differences in domestic dogs' (Canis familiaris) comprehension of human communicative signals

Journal Article Interaction Studies · September 28, 2009 Recent research suggests that some human-like social skills evolved in dogs (Canis familiaris) during domestication as an incidental by-product of selection for "tame" forms of behavior. It is still possible, however, that the social skills of certain dog ... Full text Cite

Testing the social dog hypothesis: are dogs also more skilled than chimpanzees in non-communicative social tasks?

Journal Article Behavioural processes · July 2009 Relative to non-human primates, domestic dogs possess a number of social skills that seem exceptional-particularly in solving problems involving cooperation and communication with humans. However, the degree to which dogs' unusual skills are contextually s ... Full text Cite

Bonobos have a more human-like second-to-fourth finger length ratio (2D:4D) than chimpanzees: a hypothesized indication of lower prenatal androgens.

Journal Article Journal of human evolution · April 2009 The ratio of the second-to-fourth finger lengths (2D:4D) has been proposed as an indicator of prenatal sex differentiation. However, 2D:4D has not been studied in the closest living human relatives, chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). ... Full text Cite

Looking past the model species: diversity in gaze-following skills across primates.

Journal Article Current opinion in neurobiology · February 2009 Primates must navigate complex social landscapes in their daily lives: gathering information from and about others, competing with others for food and mates, and cooperating to obtain rewards as well. Gaze-following often provides important clues as to wha ... Full text Open Access Cite

Great apes prefer cooked food.

Journal Article Journal of human evolution · August 2008 The cooking hypothesis proposes that a diet of cooked food was responsible for diverse morphological and behavioral changes in human evolution. However, it does not predict whether a preference for cooked food evolved before or after the control of fire. T ... Full text Cite

A fruit in the hand or two in the bush? Divergent risk preferences in chimpanzees and bonobos.

Journal Article Biology letters · June 2008 Human and non-human animals tend to avoid risky prospects. If such patterns of economic choice are adaptive, risk preferences should reflect the typical decision-making environments faced by organisms. However, this approach has not been widely used to exa ... Full text Open Access Cite

Science priorities. Inappropriate use and portrayal of chimpanzees.

Journal Article Science (New York, N.Y.) · March 2008 Full text Cite

Do chimpanzees reciprocate received favours?

Journal Article Animal Behaviour · January 1, 2008 Reciprocal interactions observed in animals may persist because individuals keep careful account of services exchanged with each group member. To test whether chimpanzees, Pan troglodytes, possess the cognitive skills required for this type of contingency- ... Full text Cite

The evolutionary origins of human patience: temporal preferences in chimpanzees, bonobos, and human adults.

Journal Article Current biology : CB · October 2007 To make adaptive choices, individuals must sometimes exhibit patience, forgoing immediate benefits to acquire more valuable future rewards [1-3]. Although humans account for future consequences when making temporal decisions [4], many animal species wait o ... Full text Open Access Cite

Humans have evolved specialized skills of social cognition: the cultural intelligence hypothesis.

Journal Article Science (New York, N.Y.) · September 2007 Humans have many cognitive skills not possessed by their nearest primate relatives. The cultural intelligence hypothesis argues that this is mainly due to a species-specific set of social-cognitive skills, emerging early in ontogeny, for participating and ... Full text Cite

Spontaneous altruism by chimpanzees and young children.

Journal Article PLoS biology · July 2007 People often act on behalf of others. They do so without immediate personal gain, at cost to themselves, and even toward unfamiliar individuals. Many researchers have claimed that such altruism emanates from a species-unique psychology not found in humans' ... Full text Cite

Engineering human cooperation : DDDDDoes involuntary neural activation increase public goods contributions?

Journal Article Human Nature · June 1, 2007 In a laboratory experiment, we use a public goods game to examine the hypothesis that human subjects use an involuntary eye-detector mechanism for evaluating the level of privacy. Half of our subjects are "watched" by images of a robot presented on their c ... Full text Cite

Tolerance allows bonobos to outperform chimpanzees on a cooperative task.

Journal Article Current biology : CB · April 2007 To understand constraints on the evolution of cooperation, we compared the ability of bonobos and chimpanzees to cooperatively solve a food-retrieval problem. We addressed two hypotheses. The "emotional-reactivity hypothesis" predicts that bonobos will coo ... Full text Cite

From nonhuman to human mind: What changed and why?

Journal Article Current Directions in Psychological Science · April 1, 2007 Two questions regarding the human mind challenge evolutionary theory: (a) What features of human psychology have changed since humans' lineage split from that of the other apes such as chimpanzees and bonobos? And (b) what was the process by which such der ... Full text Cite

Reliance on head versus eyes in the gaze following of great apes and human infants: the cooperative eye hypothesis.

Journal Article Journal of human evolution · March 2007 As compared with other primates, humans have especially visible eyes (e.g., white sclera). One hypothesis is that this feature of human eyes evolved to make it easier for conspecifics to follow an individual's gaze direction in close-range joint attentiona ... Full text Cite

Spontaneous altruism by chimpanzees and young children

Journal Article PLoS Biology · 2007 People often act on behalf of others. They do so without immediate personal gain, at cost to themselves, and even toward unfamiliar individuals. Many researchers have claimed that such altruism emanates from a species-unique psychology not found in humans' ... Full text Cite

Chimpanzees deceive a human competitor by hiding.

Journal Article Cognition · October 2006 There is little experimental evidence that any non-human species is capable of purposefully attempting to manipulate the psychological states of others deceptively (e.g., manipulating what another sees). We show here that chimpanzees, one of humans' two cl ... Full text Cite

Engineering cooperation in chimpanzees: tolerance constraints on cooperation

Journal Article Animal Behaviour · August 1, 2006 The cooperative abilities of captive chimpanzees, Pan troglodytes, in experiments do not match the sophistication that might be predicted based on their naturally occurring cooperative behaviours. This discrepancy might partly be because in previous experi ... Full text Cite

What's in it for me? Self-regard precludes altruism and spite in chimpanzees.

Journal Article Proceedings. Biological sciences · April 2006 Sensitivity to fairness may influence whether individuals choose to engage in acts that are mutually beneficial, selfish, altruistic, or spiteful. In a series of three experiments, chimpanzees (Pan troglodytes) could pull a rope to access out-of-reach food ... Full text Cite

Chimpanzees recruit the best collaborators.

Journal Article Science (New York, N.Y.) · March 2006 Humans collaborate with non-kin in special ways, but the evolutionary foundations of these collaborative skills remain unclear. We presented chimpanzees with collaboration problems in which they had to decide when to recruit a partner and which potential p ... Full text Cite

Is there a simple recipe for how to make friends?

Journal Article Trends in cognitive sciences · October 2005 Full text Cite

Human-like social skills in dogs?

Journal Article Trends in cognitive sciences · September 2005 Domestic dogs are unusually skilled at reading human social and communicative behavior--even more so than our nearest primate relatives. For example, they use human social and communicative behavior (e.g. a pointing gesture) to find hidden food, and they k ... Full text Cite

Social cognitive evolution in captive foxes is a correlated by-product of experimental domestication.

Journal Article Current biology : CB · February 2005 Dogs have an unusual ability for reading human communicative gestures (e.g., pointing) in comparison to either nonhuman primates (including chimpanzees) or wolves . Although this unusual communicative ability seems to have evolved during domestication , it ... Full text Cite

'Unwilling' versus 'unable': chimpanzees' understanding of human intentional action.

Journal Article Developmental science · September 2004 Understanding the intentional actions of others is a fundamental part of human social cognition and behavior. An important question is therefore whether other animal species, especially our nearest relatives the chimpanzees, also understand the intentional ... Full text Cite

Chimpanzees are more skilful in competitive than in cooperative cognitive tasks

Journal Article Animal Behaviour · September 1, 2004 In a series of four experiments, chimpanzees, Pan troglodytes, were given two cognitive tasks, an object choice task and a discrimination task (based on location), each in the context of either cooperation or competition. In both tasks chimpanzees performe ... Full text Cite

Chimpanzees versus humans: It's not that simple

Journal Article Trends in Cognitive Sciences · June 1, 2003 Full text Cite

Chimpanzees understand psychological states - The question is which ones and to what extent

Journal Article Trends in Cognitive Sciences · April 1, 2003 New data suggest that relatively drastic revisions are needed in our theoretical accounts of what other animal species understand about the psychological states of others. Specifically, chimpanzees seem to understand some things about what others do and do ... Full text Cite

Do capuchin monkeys, Cebus apella, know what conspecifics do and do not see?

Journal Article Animal Behaviour · January 1, 2003 Capuchin monkeys were tested in five experiments in which two individuals competed over food. When given a choice between retrieving a piece of food that was visible or hidden from the dominant, subordinate animals preferred to retrieve hidden food. This p ... Full text Cite

The domestication of social cognition in dogs.

Journal Article Science (New York, N.Y.) · November 2002 Dogs are more skillful than great apes at a number of tasks in which they must read human communicative signals indicating the location of hidden food. In this study, we found that wolves who were raised by humans do not show these same skills, whereas dom ... Full text Cite

Can competitive paradigms increase the validity of experiments on primate social cognition?

Journal Article Animal Cognition · December 1, 2001 Experiments vary in their ability to distinguish between competing hypotheses. In tests on primate cognition the majority of this variation is due to an experimenter's ability to test primates in valid settings while providing the adequate amount of experi ... Full text Cite

Do chimpanzees know what conspecifics know?

Journal Article Animal Behaviour · January 1, 2001 We conducted three experiments on social problem solving by chimpanzees, Pan troglodytes. In each experiment a subordinate and a dominant individual competed for food, which was placed in various ways on the subordinate's side of two opaque barriers. In so ... Full text Cite

The ontogeny of gaze following in chimpanzees, Pan troglodytes, and rhesus macaques, Macaca mulatta

Journal Article Animal Behaviour · January 1, 2001 Primates follow the gaze direction of conspecifics to outside objects. We followed the ontogeny of this social-cognitive skill for two species: rhesus macaques and chimpanzees, in the first two experiments, using both a cross-sectional and a longitudinal d ... Full text Cite

Cues to food location that domestic dogs (Canis familiaris) of different ages do and do not use

Journal Article Animal Cognition · December 1, 2000 The results of three experiments are reported. In the main study, a human experimenter presented domestic dogs (Canis familiaris) with a variety of social cues intended to indicate the location of hidden food. The novel findings of this study were: (1) dog ... Full text Cite

Chimpanzees know what conspecifics do and do not see

Journal Article Animal Behaviour · January 1, 2000 We report a series of experiments on social problem solving in chimpanzees, Pan troglodytes. In each experiment a subordinate and a dominant individual were put into competition over two pieces of food. In all experiments dominants obtained virtually all o ... Full text Cite

Chimpanzee predation and the ecology of microbial exchange

Journal Article Microbial Ecology in Health and Disease · January 1, 2000 Hunting provides one mechanism for the transmission of microbes across host species boundaries. It has generally been assumed that this mechanism leads to unidirectional transmission to humans. We report that wild chimpanzees occasionally prey on human chi ... Full text Cite

Chimpanzees, Pan troglodytes, follow gaze direction geometrically

Journal Article Animal Behaviour · January 1, 1999 Two experiments on chimpanzee gaze following are reported. In the first, chimpanzee subjects watched as a human experimenter looked around various types of barriers. The subjects looked around each of the barriers more when the human had done so than in a ... Full text Cite

Chimpanzee use of human and conspecific social cues to locate hidden food

Journal Article Developmental Science · January 1, 1999 Two studies are reported in which chimpanzees attempted to use social cues to locate hidden food in one of two possible hiding places. In the first study four chimpanzees were exposed to a local enhancement cue (the informant approached and looked to the l ... Full text Cite

Domestic dogs (Canis familiaris) use human and conspecific social cues to locate hidden food

Journal Article Journal of Comparative Psychology · January 1, 1999 Ten domestic dogs (Canis familiaris) of different breeds and ages were exposed to 2 different social cues indicating the location of hidden food, each provided by both a human informant and a conspecific informant (for a total of 4 different social cues). ... Full text Cite

Five primate species follow the visual gaze of conspecifics

Journal Article Animal Behaviour · January 1, 1998 Individuals from five primate species were tested experimentally for their ability to follow the visual gaze of conspecifics to an outside object. Subjects were from captive social groups of chimpanzees, Pan troglodytes, sooty mangabeys, Cercocebus atys to ... Full text Cite