Recent studies have shown that contrary to expectation, larger-brained species within mammalian orders are not more likely to engage in play. This is true for juvenile rodents, juvenile marsupials and adult primates. Neither does the relative size of the neocortex predict the prevalence of play in species of marsupials and...
Differences in play can illuminate differences in affiliation: A comparative study on chimpanzees and gorillas
Play behaviour reinforces social affiliation in several primate species, including humans. Via a comparative approach, we tested the hypothesis that play dynamics in a group of lowland gorillas (Gorilla gorilla gorilla) are different from those in a group of chimpanzees (Pan troglodytes) as a reflection of their difference in social...
In Play We Trust. Rapid Facial Mimicry Predicts the Duration of Playful Interactions in Geladas
The primate play-face is homologous to the human facial display accompanying laughter. Through facial mimicry, the play-face evokes in the perceiver a similar positive emotional state. This sensorimotor and emotional sharing can be adaptive, as it allows individuals to fine-tune their own motor sequences accordingly thus increasing cooperation in play....
Chimpanzee and gorilla humor: Progressive emergence from origins in the wild to captivity to sign language learning
This article examines available (mainly anecdotal) evidence related to the experience of humor among chimpanzees and gorillas in the wild, in captivity and following systematic sign language training. Humor is defined as one form of symbolic play. Positive evidence of object permanence, cross-modal perception, deferred imitation and deception among chimpanzees...
Play behavioural tactics under space reduction: social challenges in bonobos, Pan paniscus
Several studies have suggested that primates vary in their response to spatial reduction, which represents a challenge for captive animals. Under spatial reduction, primates can adopt various strategies to reduce social tension. Such strategies, which are not mutually exclusive, can involve avoidance and coping tactics. Recently, it has been shown...
Stranger to familiar: Wild strepsirhines manage xenophobia by playing
The power of play in limiting xenophobia is a well-known phenomenon in humans. Yet, the evidence in social animals remains meager. Here, we aim to determine whether play promotes social tolerance toward strangers in one of the most basal group of primates, the strepsirhines. We observed two groups of wild...
The Avatar’s new clothes: Understanding why players purchase non-functional items in free-to-play games
Free-to-play online games create significant revenues through sales of virtual items. The argument that the sale of items that provide a competitive advantage (functional items) fuels a pay-to-win culture has attracted developers to business models that are solely based on the sale of non-functional items (items that provide no objective...
Facial Mimicry and Play: A Comparative Study in Chimpanzees and Gorillas
play fighting, a common form of mammalian play, can escalate into aggression if playful motivation is misinterpreted and not shared by players. In primates, playful facial expressions and mimicry can be performed to signal and share playful motivation. Here we compare play facial expressions (play face [PF]: lower teeth exposed;...
Play and social dynamics in a captive herd of gelada baboons (Theropithecus gelada)
Here, we provide quantitative data concerning adult and immature play distribution in geladas discussing the results in the light of their social dynamics. Sex differences in immature play does not seem to reflect sex differences in adult role; in fact, frequency, modality (C-play and LR-play), and motivation (measured by play...
Anatomy is important, but need not be destiny: Novel uses of the thumb in aye-ayes compared to other lemurs
Aye-ayes (. Daubentonia madagascerensis) have highly specialized hands with long digits, especially the thin middle one (D3), which is used for extracting food, such as beetle larvae, under bark. Due to the elongation of their fingers, including the thumb, it is presumed that aye-ayes have a rather limited capacity for...
Playing With the Face: Playful Facial “Chattering” and Signal Modulation in a Monkey Species (Theropithecus gelada)
Darwin (1872), in The expression of emotions in man and animals, underlined that human facial expressions represent a shared heritage of our species with nonhuman primates. Play is a fertile field to examine the role of facial expressions that we share with our common ancestors because the primate play face...
Integrating Tinbergen’s inquiries: Mimicry and play in humans and other social mammals
Visual signals convey emotions and intentions between individuals. Darwin underlined that human facial expressions represent a shared heritage between our species and many other social mammals. Social play is a fertile field to examine the role and the potential communicative function of facial expressions. The relaxed open-mouth (or play face)...
High-Ranking Geladas Protect and Comfort Others After Conflicts
Post-conflict affiliation is a mechanism favored by natural selection to manage conflicts in animal groups thus avoiding group disruption. Triadic affiliation towards the victim can reduce the likelihood of redirection (benefits to third-parties) and protect and provide comfort to the victim by reducing its post-conflict anxiety (benefits to victims). Here,...
The archaeology of mind [extracts]
To the best of our knowledge, the basic biological values of all mammalian brains were built upon the same basic plan, laid out in consciousness-creating affective circuits that are concentrated in subcortical regions, far below the neocortical "thinking cap " that is so highly developed in humans. Mental life would...
Primate play laughing: A comparison between immature great apes and humans
Introduction to the paper: In primates, playful interactions are often accompanied by specific facial expressions (van Hooff and Preuschoft, 2003). In the great apes, these expressions can be performed in two different ways: play face, where the mouth is opened with only the lower teeth exposed, and full play face,...
Sharing the motivation to play: the use of signals in adult bonobos
Gestures and facial displays are involved in regulating many aspects of mammal social life such as aggression, dominance-subordinate relationships, appeasement and play. Playful activity is an interesting behaviour for examining the role of signals as intentional communication systems. When animals play they perform patterns that are used in other serious...
Immediate and delayed benefits of play behaviour: New evidence from Chimpanzees (Pan troglodytes)
Evidence for the anticipation of competition at feeding time has been previously documented in both Pan species. Chimpanzees seem to cope with competitive tendency through behavioural mechanisms of tension reduction, and grooming is certainly one of these. Social play and grooming are often matched because they bring animals into close...
Comparative analyses of the role of postnatal development on the expression of play fighting
Whether it is that animals are young so that they can play, or whether it is that they play because they are young, play should be more prevalent in species that have a greater degree of postnatal development. This hypothesis is tested by comparative analyses within two mammalian orders (primates...
The influence of phylogeny on the social behaviour of macaques (Primates: Cercopithecidae, genus Macaca)
The macaques are the most geographically widespread and behaviourally diverse primate genus. Many of the diversified features of social behaviour and organization in this genus have been attributed to socio-ecological differences. However, some core aspects of social behaviour and organization appear to be highly conservative, suggesting a high degree of...
Short-Term Benefits of Play Behavior and Conflict Prevention in Pan paniscus [chimps & bonobos]
Most theories on the function of play have focused on ultimate rather than proximate benefits. Play peaks during juvenility but, in some species, it is present in adulthood as well. In primates, social play and grooming often show a matched pattern because they bring individuals into close contact and favor...
