Carel P van Schaik

Carel P van Schaik
University of Zurich | UZH · Department of Anthropology und Anthropological Museum

PhD

About

680
Publications
203,508
Reads
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38,043
Citations
Introduction
Carel P van Schaik is retired from the Department of Anthropology and Anthropological Museum, University of Zurich (Switzerland), and currently affiliated with the Department of Evolutionary Biology and Environmental Science and the Center for the Interdisciplinary Study of Language Evolution (ISLE). He is also a fellow of the MPI Animal Behavior in Konstanz (Germany). He does research in evolutionary anthropology, animal communication, behavioral ecology and human evolutionary biology.
Additional affiliations
June 2004 - present
University of Zurich
Position
  • Professor (Full)
June 2004 - August 2018
University of Zurich
Position
  • Managing Director
June 1989 - August 2004
Duke University
Position
  • Professor (Full)

Publications

Publications (680)
Article
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Human hyper-cooperativity and the emergence of division of labor enables us to not only solve problems effectively within a group but also collectively. Collective problem solving occurs when groups perform better than the additive performance of separate individuals. Currently, it is unknown whether this is unique to humans. To investigate the evo...
Article
Communicative repair is a fundamental and universal element of interactive language use. It has been suggested that the persistence and elaboration after communicative breakdown in nonhuman primates constitute two evolutionary building blocks of this capacity, but the conditions favouring it are poorly understood. Because zoo-housed individuals of...
Article
To understand the primate origins of the human interaction engine, it is worthwhile to focus not only on great apes but also on callitrichid monkeys (marmosets and tamarins). Like humans, but unlike great apes, callitrichids are cooperative breeders, and thus habitually engage in coordinated joint actions, for instance when an infant is handed over...
Preprint
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Our understanding of the considerable variation in vertebrate brain size remains incomplete. Large brains are adaptive but brains require unusually high, near-constant energy inputs, and are prioritized energy targets. This trade-off also has understudied developmental consequences: immatures must develop a fully functional brain without already ha...
Article
Across the animal kingdom, we see remarkable variation in brain size. This variation has even increased over evolutionary time. Traditionally, studies aiming to explain brain size evolution have looked at the fitness benefits of increased brain size in relation to its increased cognitive performance in the social and/or ecological domain. However,...
Article
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Between-individual variation in behavioural expression, such as social responsiveness, has been shown to have important eco-evolutionary consequences. However, most comparative research on non-human primate communication has focused on species- or population-level variation, while among- and within-individual variation has been largely ignored or c...
Article
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In many group-living mammals, philopatric females form the stable core of the group and defend food or shelter against other groups of females. Where males are larger, their participation could give their female group the edge. How can females secure the contribution of males that are neither the father of current infants, nor the dominant male exp...
Article
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Humans communicate with small children in unusual and highly conspicuous ways (child-directed communication (CDC)), which enhance social bonding and facilitate language acquisition. CDC-like inputs are also reported for some vocally learning animals, suggesting similar functions in facilitating communicative competence. However, adult great apes, o...
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As climate change continues to fundamentally alter resource landscapes, the ability to flexibly respond to spatio-temporal changes in the distribution of preferred food sources is increasingly important for the overall health and fitness of animals living in seasonal, variable, and/or changing environments. Here, we investigate the effects of an un...
Article
This paper surveys five human societal types – mobile foragers, horticulturalists, pre-state agriculturalists, state-based agriculturalists, and liberal democracies – from the perspective of three core social problems faced by interacting individuals: coordination problems, social dilemmas, and contest problems. We characterize the occurrence of th...
Preprint
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This paper surveys five human societal types -- mobile foragers, horticulturalists, pre-state agriculturalists, state-based agriculturalists, and liberal democracies -- from the perspective of three core social problems faced by interacting individuals: coordination problems, social dilemmas, and contest problems. We characterize the occurrence of...
Preprint
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Larger brains should be adaptive because they support numerous eco- and socio-cognitive benefits, but these benefits explain only a modest part of the interspecific variation in brain size. Notably underexplored are the high energetic costs of developing brains, and thus the possible role of parental provisioning in the evolution of adult brain siz...
Article
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Whether nonhuman species can change their communicative repertoire in response to socio-ecological environments has critical implications for communicative innovativeness prior to the emergence of human language, with its unparalleled productivity. Here, we use a comparative sample of wild and zoo-housed orang-utans of two species (Pongo abelii, P....
Article
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Scientists have long struggled to establish how larger brains translate into higher cognitive performance across species. While absolute brain size often yields high predictive power of performance, its positive correlation with body size warrants some level of correction. It is expected that larger brains are needed to control larger bodies withou...
Article
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In species in which adults of the two sexes show long‐term association, males often engage in acts of assistance (“services”) aimed at females and/or their young in various behavioural contexts that are not reciprocated. We conducted a quantitative review of the primate literature on sex differences in involvement in protection against predation. W...
Article
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From early infancy, human face-to-face communication is multimodal, comprising a plethora of interlinked communicative and sensory modalities. Although there is also growing evidence for this in nonhuman primates, previous research rarely disentangled production from perception of signals. Consequently, the functions of integrating articulators (i....
Article
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Both absolute and relative brain sizes vary greatly among and within the major vertebrate lineages. Scientists have long debated how larger brains in primates and hominins translate into greater cognitive performance, and in particular how to control for the relationship between the noncognitive functions of the brain and body size. One solution to...
Article
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To resolve the major controversy about why prosocial behaviors persist in large-scale human societies, we propose that two questions need to be answered. First, how do social interactions in small-scale and large-scale societies differ? By reviewing the exchange and collective-action dilemmas in both small-scale and large-scale societies, we show t...
Article
Full-text available
To resolve the major controversy about why prosocial behaviors persist in large‐scale human societies, we propose that two questions need to be answered. First, how do social interactions in small‐scale and large‐scale societies differ? By reviewing the exchange and collective‐action dilemmas in both small‐scale and large‐scale societies, we show t...
Article
Full-text available
As a part of growing up, immature orangutans must acquire vast repertoires of skills and knowledge, a process that takes several years of observational social learning and subsequent practice. Adult female and male orangutans show behavioral differences including sex-specific foraging patterns and male-biased dispersal. We investigated how these di...
Article
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Orangutans show a pronounced sexual dimorphism, with flanged males (i.e., males with fully grown secondary sexual characteristics) reaching twice the size of adult females. Furthermore, adult orangutans show sex-specific dispersal and activity patterns. This study investigates sex differences in adult foraging behavior and sheds light on how these...
Preprint
Full-text available
Both absolute and relative brain size vary greatly among and within the major vertebrate lineages. Scientists have long debated how larger brains in primates and hominins translate into greater cognitive performance, and in particular how to control for the relationship between the non-cognitive functions of the brain and body size. One solution to...
Preprint
Full-text available
There are two well-established facts about vertebrate brains: brains are physiologically costly organs, and both absolute and relative brain size varies greatly between and within the major vertebrate clades. While the costs are relatively clear, scientists struggle to establish how larger brains translate into higher cognitive performance. Part of...
Preprint
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The creation of novel communicative acts is an essential element of human language. Although some research suggests the presence of this ability in great apes, this claim remains controversial. Here, we use orang-utans (Pongo spp.) to systematically assess the effect of the wild-captive contrast on the repertoire size of communicative acts. We find...
Article
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Social tolerance in a group reflects the balance between within-group competition and interdependence: whereas increased competition leads to a reduction in social tolerance, increased interdependence increases it. Captivity reduces both feeding competition and interdependence and can therefore affect social tolerance. In independently breeding pri...
Article
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Sexual coercion, in the form of forced copulations, is relatively frequently observed in orangutans and generally attributed to their semi-solitary lifestyle. High ecological costs of association for females may be responsible for this lifestyle and may have prevented the evolution of morphological fertility indicators (e.g., sexual swellings), whi...
Preprint
Full-text available
From early infancy, human face-to-face communication is “multimodal”, comprising a plethora of interlinked articulators and sensory modalities. Although there is also growing evidence for this in nonhuman primates, the functions of integrating articulators (i.e. multiplex or multi-articulator acts) and channels (i.e. multimodal or multi-sensory act...
Article
Full-text available
The zone of latent solutions (ZLS) hypothesis provides an alternative approach to explaining cultural patterns in primates and many other animals. According to the ZLS hypothesis, non-human great ape (henceforth: ape) cultures consist largely or solely of latent solutions. The current competing (and predominant) hypothesis for ape culture argues in...
Article
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The uniquely enlarged noses of male proboscis monkeys are prominent adornments, and a sexually selected male trait. A recent study showed significant correlations among nose, body, and testis sizes and clear associations between nose size and the number of females in a male's harem. However, to date, the analyses of other common male traits, i.e.,...
Article
Primates, like other mammals, exhibit an annual reproductive pattern that ranges from strictly seasonal breeding to giving birth in all months of the year, but factors mediating this variation are not fully understood. We applied both a categorical description and quantitative measures of the birth peak breadth based on daily observations in zoos t...
Article
The potential for rituals in non-human great apes (apes) is an understudied topic. We derive a minimal definition of ritual and then examine the currently available evidence for it in untrained and non-enculturated apes. First, we examine whether such apes show evidence for the two main components of our minimal definition of ritual: symbolism and...
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Neural development is highly conserved across distantly related species of different brain sizes. Here, we show that the development of manipulative complexity is equally cumulative across 36 primate species and also that its ontogeny recapitulates phylogeny. Furthermore, larger-brained species reach their adult skill levels later than smaller-brai...
Book
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Dieses Themenheft unserer Sitzungsberichte ist das Ergebnis der Jahrestagung der Gesellschaft Naturforschender Freunde zu Berlin Anfang Juni 2016. Der Bogen spannt sich von der Phylogenie und Genetik bis zu einem spezifischen Parasiten als Teil unserer Umwelt. Doch liegt der Schwerpunkt in der Auseinandersetzung mit den Fragen danach, was uns zum M...
Article
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Most human societies exhibit a distinct class structure, with an elite, middle classes, and a bottom class, whereas animals form simple dominance hierarchies in which individuals with higher fighting ability do not appear to form coalitions to “oppress” weaker individuals. Here, we extend our model of primate coalitions and find that a division int...
Article
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Marmoset monkeys show high levels of proactive prosociality, a trait shared with humans, presumably because both species rely on allomaternal care. However, it is not clear whether the proximate regulation of this convergent trait is also similar, in particular with regard to intentionality, which is a defining characteristic of prosocial behavior...
Article
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Female orangutans exhibit natal philopatry, living in stable home ranges that overlap with those of their maternal relatives. Using data collected from 2003 to 2017 at Tuanan in Central Kalimantan, Indonesia, we take a longitudinal approach to better understand the mechanisms of female philopatry and the factors that influence the home range establ...
Article
While signals in evolutionary biology are usually defined as "acts or traits that have evolved because of their effect on others", work on gestures and vocalizations in various animal taxa have revealed population- or even individual-specific meanings of social signals. These results strongly suggest that communicative acts that are like signals wi...
Article
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Exploration is essential for skill acquisition and strongly facilitates cognitive performance. In humans, it is widely known that exploration and later cognitive performance are highly dependent on early social inputs. Here, we aim to shed light on the evolutionary roots of this process by studying the effects of variation in opportunities for soci...
Article
Cultural anthropology and evolutionary biology arose around the same time, and both adopted the same evolutionist framework. Their paths soon diverged, however, largely because anthropology rejected the notion of evolutionary progress—and thus the notion of the existence of primitive versus advanced races—before evolutionary biology did. Most anthr...
Preprint
Full-text available
The uniquely enlarged noses of male proboscis monkeys (Nasalis larvatus) are prominent adornments, and a sexually selected male masculine trait, as recently revealed by the significant correlations among nose, body, and testis sizes and the clear association between nose size and the number of females in a male's harem. However, till date, the anal...
Chapter
Vorrede | In diesem charakteristischerweise hervorragend recherchierten Beitrag erörtern Kappeler und Fichtel die Konsequenzen sozialer und einkommensbedingter Ungleichheit für die individuelle Gesundheit und die empfundene Einsamkeit aus einer evolutionären Perspektive. Das zentrale Argument der Autoren ist, dass sich die modernen Großgesellschaft...
Chapter
Full-text available
In this chapter, we apply the affective social learning (ASL) concept to the social learning of natural skill sets in immature orang-utans since it can serve as an illustration of the majority of learning that occurs in wild apes. Most orang-utan social learning happens during everyday tasks and without any active involvement of the role model. Con...
Article
The communicative function of primates' self-directed behaviours like scratching has gained increasing attention in recent years, but their intentional use is still debated. Here, we addressed this issue by exploring the communicative function of 'loud scratches' in wild Sumatran orangutans. Building on previous studies in chimpanzees, we examined...
Chapter
This chapter explores the notion that the behavioural and cognitive constituents of human social norms have equivalents or precursors in humans’ closest living relatives, the non-human primates. Scrutiny of the definitions of various forms of conformity revealed, on the one hand, that some key features defining social norms are essentially impossib...
Chapter
Normative behavior is a human universal that is intimately linked to morality. Morality is an adaptation to the specifically human subsistence niche of hunting and gathering, which is skill-intensive and therefore relies on transmission of opaque knowledge and involves critical interdependence, reliance on coordinated division of labor, and synchro...
Chapter
Wir zeichnen nach, auf welchen Wegen sich die kulturelle Evolution des Monotheismus vollzog. Die angeborenen Eigenarten des menschlichen Denkens bilden die Grundlage für die Entwicklung von Religionen. Dazu gehören unser Dualismus (der Geist ist unabhängig vom Körper) und unsere Neigung, alle Kausalität sozial, das heißt alle Ereignisse als Handlun...
Article
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Housing primates in naturalistic groups provides social benefits relative to solitary housing. However, food intake may vary across individuals, possibly resulting in overweight and underweight individuals. Information on relative adiposity (the amount of fat tissue relative to body weight) is needed to monitor overweight and underweight of group-h...
Article
The presence of divergent and independent research traditions in the gestural and vocal domains of primate communication has resulted in major discrepancies in the definition and operationalization of cognitive concepts. However, in recent years, accumulating evidence from behavioural and neurobiological research has shown that both human and non‐h...
Article
Full-text available
The expensive brain hypothesis predicts that the lowest stable level of energy input sets the upper limit to a species’ brain size. This prediction receives comparative support from the effects of experienced seasonality (including hibernation) and diet quality on mammalian brain size. Here, we test another prediction, which concerns the temporal s...
Preprint
To resolve the major controversy about how large-scale societies could ever evolve and be maintained, we propose that two questions need to be answered. First, how do social interactions in small-scale and large-scale societies differ? By reviewing the exchange and collective-action dilemmas in both small-scale and large-scale societies, we show th...
Article
“Self‐domestication” has been invoked to understand important aspects of human evolution, integrating physiological, behavioral, and morphological information in a novel way. It proposes that selection for reduced aggression on animals undergoing domestication provides a model for selection favoring prosocial behaviors in humans and for a set of se...
Article
Full-text available
Many animals, and in particular great apes, show evidence of culture, in the sense of having multiple innovations in multiple domains whose frequencies are influenced by social learning. But only humans show strong evidence of complex, cumulative culture, which is the product of copying and the resulting effect of cumulative cultural evolution. The...
Article
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For humans we implicitly assume that the way we do things is the product of social learning and thus cultural. For animals, this conclusion requires proof. Here, we first review the most commonly used procedure for documenting animal culture: the method of exclusion, which charts geographic behavioral variation between populations as evidence for c...
Article
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Background Integrating demography and adaptive evolution is pivotal to understanding the evolutionary history and conservation of great apes. However, little is known about the adaptive evolution of our closest relatives, in particular if and to what extent adaptions to environmental differences have occurred. Here, we used whole-genome sequencing...
Article
Orangutans (Pongo spp.) are reported to have extremely slow life histories, including the longest average interbirth intervals of all mammals. Such slow life history can be viable only when unavoidable mortality is kept low. Thus, orangutans’ survivorship under natural conditions is expected to be extremely high. Previous estimates of orangutan lif...
Article
For over a century, theories of human intelligence have concentrated on a single general factor, the psychometric g, which is used to estimate reasoning ability and cognitive flexibility, i.e. general intelligence. To better understand the evolution of general intelligence, it is important to identify the presence of a psychometric g in nonhuman an...
Article
Full-text available
Cultural primatology focuses on the study of culture in nonhuman primates. Culture is defined as innovations that are spread and maintained between and within generations by social learning. The principal method used to establish the presence of culture in nature is the “method of exclusion.” It states that cultural processes can be inferred if a b...
Chapter
Cultural primatology focuses on the study of culture in nonhuman primates. Culture is defined as innovations that are spread and maintained between and within generations by social learning. The principal method used to establish the presence of culture in nature is the “method of exclusion.” It states that cultural processes can be inferred if a b...
Article
Full-text available
Language is commonly narrowed down to speech, but human face-to-face communication is in fact an intrinsically multimodal phenomenon. Despite growing evidence that the communication of non-human primates, our main model for the evolution of language, is also inherently multimodal, most studies on primate communication have focused on either gesture...
Article
Social learning in animals is now well documented, but few studies have determined the contexts shaping when social learning is deployed. Theoretical studies predict copying of conspecifics gaining higher payoffs [1-4], a bias demonstrated in primates only in captivity [5]. In the wild, research has shown selective attention toward the philopatric...
Article
Full-text available
The expensive brain hypothesis predicts that the lowest stable level of steady energy input acts as a strong constraint on a species’ brain size, and thus that periodic troughs in net energy intake should select for reduced brain size relative to body mass. Here, we test this prediction for the extreme case of hibernation. Hibernators drastically r...
Article
We welcome Tomasello’s new book on the natural history of human morality as an important confirmation of the evolutionary approach, which sees adaptive behaviors and their psychological underpinnings as linked to a species’ socioecology (the package of subsistence, social, mating, and rearing systems). This perspective automatically leads to the co...
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The aim of this contribution is to explore the origins of moral behavior and its underlying moral preferences and intuitions from an evolutionary perspective. Such a perspective encompasses both the ultimate, adaptive function of morality in our own species, as well as the phylogenetic distribution of morality and its key elements across primates....
Article
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In numerous social species, males direct aggression towards female group members during intergroup fights, and this behaviour is commonly thought to function as mate guarding, even though males often target non-receptive females. In studying intergroup fights in a wild population of vervet monkeys, we found that male intragroup aggression was prima...