Elisabetta Palagi

Università di Pisa | UNIPI · Department of Biology - Unit of Ethology

Psychological, clinical and neurobiological findings endorse that empathic abilities are more developed in women than in men. Because there is growing evidence that yawn contagion is an empathy-based phenomenon, we expect that the female bias in the empathic abilities reflects on a gender skew in the responsiveness to others' yawns. We verified thi...

Comparative thanatology includes the scientific study of death in non-human animals, which involves emotional, social, and exploratory responses of individuals and groups towards corpses. Stillborn babies and dead infants often elicit maternal and alloparental care that can persist for days, weeks, or even months, especially in primates. After this...

Play is generally considered an immature affair. However, adult play is present in several mammal species living in complex social systems. Here, I hypothesize that adult social play is favored by natural selection in those species characterized by high level of social tolerance and/or by the need of others’ cooperation to reach a goal (i.e., lever...

Humans are social animals that rely on different ways to interact with each other. The COVID-19 pandemic strongly changed our communication strategies. Because of the importance of direct contact for our species, we predict that immediately after the forced social isolation, people were more prone to engage in direct rather than in virtual interact...

Dominance hierarchies can be interconnected with behaviours that are essential to manage social living, such as affiliative behaviours and social play, whose importance can already emerge in the early phases of life. Here, we carried out an observational study (all occurrences sampling) to investigate the possible interconnection between these thre...

This special issue of the International Journal of Play is devoted to the evolution and ontogeny of play and includes papers on various animals, children, and a diversity of phenomena all related to this theme. Papers in the issue provide original data on these species: rheas, Beluga whales, wolves, Japanese monkeys, gorillas, and human children as...

Stone handling (SH) is a form of solitary object play widely documented in four species of macaques and most recently also in geladas ( Theropithecus gelada ). Here, we describe the SH activity of two mother-reared captive gelada males, who combined different behavioral patterns in a sequence that occasionally led to the production of colored marks...

Yawning is a complex behaviour linked to several physiological (e.g. drowsiness, arousal, thermoregulation) and social phenomena (e.g. yawn contagion). Being yawning an evolutionary well-conserved, fixed action pattern widespread in vertebrates, it is a valuable candidate to test hypotheses on its potential functions across the different taxa. The...

Human laughter and laugh faces show similarities in morphology and function with animal playful expressions. To better understand primordial uses and effects of human laughter and laugh faces, it is important to examine these positive expressions in animals from both homologous and analogous systems. Phylogenetic research on hominids provided empir...

This opinion piece aims to tackle the biological, psychological, neural and cultural underpinnings of laughter from a naturalistic and evolutionary perspective. A naturalistic account of laughter requires the revaluation of two dogmas of a longstanding philosophical tradition, that is, the quintessential link between laughter and humour, and the un...

One contribution of 17 to a theme issue 'Cracking the laugh code: laughter through the lens of biology, psychology, and neuroscience'.

The ring-necked parakeet Psittacula krameri (Aves: Psittaciformes) is a widely distributed species of Asian and African origin, which occurs with over 40 alien populations in the rest of the world. Most established populations of this species are showing a clear trend of territorial expansion and numerical growth. Recent reviews highlighted that on...

Laughter affects conversational schemes, supports speech production, establishes social bonds and is connected to playfulness. Despite the pervasiveness of this behaviour, research on laughter has long been underdeveloped, probably because it does not sound like a serious topic. Also, its social and expressive nature represents a major technical di...

Compared to other primate taxa, hand preference in strepsirrhines has been poorly investigated and the available studies have often produced conflicting results. Thanks to their remarkable plasticity in foraging and postural habits, ring-tailed lemurs (Lemur catta) represent a key model species to examine manual lateralisation. We video-recorded 23...

Yawn contagion (YC) is, compared to spontaneous yawning, an evolutionary recent phenomenon probably linked to behavioral synchronization in highly social species that is more likely when it involves familiar subjects. Here, we investigate for the first time in monkeys which factors modulate intra- and interspecific YC. Through an experimental appro...

The commentary by Gallup and Anderson (Anim Cogn https:// doi. org/ 10. 1007/ s10071-021-01538-9, 2021) on the original article by Baragli, Scopa, Maglieri, and Palagi (Anim Cogn https:// doi. org/ 10. 1007/ s10071-021-01502-7, 2021) raised some concerns about the methodological approach used by the authors to demonstrate Mirror Self-Recognition (M...

Play fighting, the most iconic form of social play, is often punctuated by specific signals, such as the relaxed open mouth (ROM) display, limiting the risk of misunderstanding between playmates. Although there is general consensus that the ROM of dogs is a ritualized version of play biting, the empirical demonstration of the actual ritualization o...

Dogs engage in play behavior at every age and the play bow is their most iconic playful posture. However, the function of this posture is still under debate. Here, we selected the Czechoslovakian Wolfdog as a model breed to clarify the function of the play bow. We analyzed frame-by-frame 118 sessions of 24 subjects and recorded 76 play bow events....

Dogs engage in play behavior at every age and the play bow is their most iconic playful posture. However, the function of this posture is still under debate. Here, we selected the Czechoslovakian Wolfdog as a model breed to clarify the function of the play bow. We analyzed frame-by-frame 118 sessions of 24 subjects and recorded 76 play bow events....

Play fighting, the most common form of social play in mammals, is a fertile field to investigate the use of visual signals in animals’ communication systems. Visual signals can be exclusively emitted during play (e.g. play faces, PF, context-dependent signals), or they can be released under several behavioural domains (e.g. lip-smacking, LS, contex...

The capacity to promptly and congruently respond to others’ facial signals has at its basis a mirror neuron mechanism. In Rapid (< 1 sec, RFM) and Delayed (1–5 sec, DFM) Facial Mimicry the expression emitted by an individual (trigger) is perceived and replicated by an observer. The occurrence of mimicry phenomena has been demonstrated almost exclus...

Female primates can emit vocalizations associated with mating that can function as honest signals of fertility. Here, we investigated the role of mating calls and visual signals in female geladas Theropithecus gelada. Since females have a central role in the gelada society and seem to solicit sexual interactions, we answered whether they emit vocal...

In non-human animals, the phenomenon of Rapid Facial Mimicry (RFM) - the automatic, involuntary and rapid (< 1 sec) replication of others’ facial expressions—has been mainly investigated in the playful domain. In immature lowland gorillas Gorilla gorilla gorilla both Play Face (PF) and Full Play Face (FPF) are rapidly mimicked between the players....

Cognitive ethology explores the ability of animals to flexibly adapt their behavior to rapid physical and social environment fluctuations. Although there is a historical dichotomy between field and captive studies, recently, a growing interest in questions that sit at the intersection of cognitive and adaptive perspectives has helped bridge this di...

The Biological Market Theory (BMT) posits that cooperation between non-human animals can be seen as a mutually beneficial exchange of commodities similarly to what observed in human economic markets. Positive social interactions are commodities in non-human animals, and mutual exchanges fulfilling the criteria of the BMT have been shown in several...

Communication relies on signals that can be produced via different sensory modalities to modify receivers’ behaviour. During social interactions, the possibility to perceive subtle visual cues enhances the use of facial expressions to exchange information. One of the most appropriate fields to explore the specific design features of visual signals...

Yawn contagion occurs when individuals yawn in response to the yawn of others (triggers). This is the first account of yawn contagion in wild geladas ( Theropithecus gelada ), a monkey species that shows yawn contagion in captivity and is organized in core units (one-male/bachelor groups) forming multilevel associations. In a population of geladas...

Mirror self-recognition (MSR), investigated in primates and recently in non-primate species, is considered a measure of self-awareness. Nowadays, the only reliable test for investigating MSR potential skills consists in the untrained response to a visual body mark detected using a reflective surface. Here, we report the first evidence of MSR at gro...

Infant handling - involving affiliative behavior from non-mothers to infants – is a phenomenon that is variably present in Old World monkeys and can be granted by mothers to obtain social services, such as grooming. Here we investigated for the first time whether infant handling could influence grooming exchange in wild geladas. We gathered data on...

Play fighting, the most iconic form of social play, has been hypothesized to serve multiple evolutionary roles as a function of the age of the players. Although widely practised by youngsters, in some mammal species this form of play can also be present in adults. Here, we aimed to test these hypotheses by looking at the play-fighting behaviour of...

In human and nonhuman primates eye-to-eye contact (EEC), a face-to-face communication component, can promote emotional/attentional engagement and prolong affiliative interactions. Owing to its direct impact on fitness, the reproductive context is perhaps the most critical context for investigating EEC's importance. However, the presence of this phe...

The role of play in the superfamily Otarioidea has not been widely explored. However, all play types found in other so-called “playful groups” (e.g., primates or canids) have been reported among sea lions, fur seals and walruses. Otariids and odobenids perform object play with animate and non-animate objects, such as kelp, rocks or seabirds. Locomo...

Human–primate interfaces are expanding and, despite recent studies on primates from peri-urban environments, little research exists on the impact of agriculture and/or pasture areas on primate social behavior and health. We assessed how crop/pasture areas potentially alter social behavior and health of wild geladas ( Theropithecus gelada ) frequent...

Contrary to spontaneous yawning, which is widespread in vertebrates and probably evolutionary ancient, contagious yawning—yawning triggered by others’ yawns—is considered an evolutionarily recent phenomenon, found in species characterized by complex sociality. Whether the social asymmetry observed in the occurrence of contagious yawning is related...

Here we show for the first time that the plasticity in morphology and duration of yawning in Macaca tonkeana can be associated with different functional contexts. Macaca tonkeana is classified as a tolerant macaque species characterized by social interactions minimally constrained by dominance rank or kinship. Tonkean macaques, as other egalitarian...

By gathering data on people during their ordinary daily activities, we tested if looking at, but not manipulating, smartphones led to a mimicry response in the observer. Manipulating and looking at the device (experimental condition), more than its mere manipulation (control condition), was critical to elicit a mimicry response in the observer. Sex...

Yawning, a fixed action pattern, is widespread in almost all vertebrate taxa. Several hypotheses have been proposed to explain the functions of yawning. These hypotheses, not mutually exclusive, can be conventionally arranged according to both physiological (e.g. drowsiness hypothesis: yawning when switching between sleep and being awake; arousal h...

Primate communication relies strongly on the visual modality, notably through the production of a wide range of expressive facial signals. We investigated here the facial display repertoire of a relatively little-studied cercopithecid species, red-capped mangabeys (Cercocebus torquatus), and questioned whether their facial displays were dependent o...

Yawning is a primitive and stereotyped motor action involving orofacial, laryngeal, pharyngeal, thoracic and abdominal muscles. Contagious yawning, an involuntarily action induced by viewing or listening to others' yawns, has been demonstrated in human and several non‐human species. Previous studies with humans showed that infants and preschool chi...

Two of the main hypotheses put forth to explain the function of immature social play are the Social Skill Hypothesis and the Motor Training Hypothesis focussing on whether play can improve social competence to develop cooperative social networks or physical abilities to outcompete others, respectively. Here, we tested these hypotheses on a monkey s...

Rapid Facial Mimicry (RFM), one of the possible predictors of emotional contagion, is defined as the rapid, involuntary and automatic replication of a facial expression. Up to now, RFM has been demonstrated in nonhuman animals exclusively during play. Since in bonobos, as in humans, socio-sexuality is a powerful tool for assessing/strengthening int...

In humans, eye-to-eye contact (EEC) or mutual gazing is a reflexive predisposition occurring in intimate contexts. We investigated the role of EEC during bonobo socio-sexual contacts. Females engage in homosexual ventro-ventral, genito-genital rubbing (VVGGR) during which they embrace each other while rubbing part of their vulvae and, sometimes, cl...

Stone Handling (SH) is a solitary object play behaviour that can vary from simple exploratory actions to more complex manipulations. So far, among primates, this behaviour has been exclusively reported in macaques. We collected data on 62 geladas (Theropithecus gelada) housed at the NaturZoo (Rheine, Germany). We found that about 70% of subjects be...

Contagious yawning differs from spontaneous yawning because it occurs when an individual yawns in response to someone else’s yawn. In Homo sapiens and some non-human primates contagious yawning is higher between strongly than weakly bonded individuals. Up to date, it is still unclear whether this social asymmetry underlies emotional contagion (a ba...

An important aspect in the assessment of an individual's life quality is the impact of such changes on dominance hierarchy, which in turn affects physiology, food access and reproductive success. This study measured the effect of changes in tank fish composition on the hierarchy of a stock of 10 individuals of the cichlid fish (Tropheus moorii) hos...

Social play is a window on cognitive and communicative abilities of species. Inter-specific play, in particular, is a fertile venue to explore the capacity to correctly perceive and interpret signals emitted by partners. Up to now, most studies have focussed on dog-human play due to the important implications such studies have in understanding the...

Involuntary synchronization occurs when individuals perform the same motor action patterns during a very short time lapse. This phenomenon serves an important adaptive value for animals permitting them to socially align with group fellows thus increasing integration and fitness benefits. Rapid mimicry (RM) and yawn contagion (YC) are two behavioral...

Spontaneous mimicry appears fundamental to emotional perception and contagion, especially when it involves facial emotional expressions. Here we cover recent evidence on spontaneous mimicry from ethology, psychology and neuroscience, in non-human and human animals. We first consider how mimicry unfolds in non-human animals (particularly primates) a...

Spontaneous yawning is a widespread behaviour in vertebrates. However, data on marine mammals are scarce. In this study, we tested some hypotheses on the functions of yawning in a captive group of South American sea lions (Otaria flavescens). According to the Dimorphism Hypothesis, species showing low levels of sexual dimorphism in canine size do n...

This review focuses on wolf sociobiology to delineate the traits of cooperative baggage driven by natural selection (wolf-wolf cooperation) and better understand the changes obtained by artificial selection (dog-human cooperation). We selected some behaviors of the dog’s ancestors that provide the basis for the expression of a cooperative society,...

https://doi.org/10.4000/primatologie.3846 // FROM ARTICLE: Aychet, J., Blois-Heulin, C., Palagi, E., & Lemasson, A. (2021). Facial displays in red-capped mangabeys (Cercocebus torquatus): Repertoire, social context, and potential intentionality. Journal of Comparative Psychology, 135(1), 98–113. https://doi.org/10.1037/com0000252

Human-directed gazing, a keystone in dog-human communication, has been suggested to derive from both domestication and breed selection. The influence of genetic similarity to wolves and selective pressures on human-directed gazing is still under debate. Here, we used the ‘unsolvable task’ to compare Czechoslovakian Wolfdogs (CWDs, a close-to-wolf b...

One of the most productive behavioural domains to study visual communication in mammals is social play. The ability to manage play–fighting interactions can favour the development of communicative modules and their correct decoding. Due to their high levels of social cohesion and cooperation, slender-tailed meerkats (Suricata suricatta) are a very...

Dog-Horse Play

FROM ARTICLE: Aychet, J., Blois-Heulin, C., Palagi, E., & Lemasson, A. (2021). Facial displays in red-capped mangabeys (Cercocebus torquatus): Repertoire, social context, and potential intentionality. Journal of Comparative Psychology, 135(1), 98–113. https://doi.org/10.1037/com0000252

Il ruolo delle emozioni è stato da sempre oggetto di dibattito in ambito filosofico, ancor prima che scientifico. Un grande nodo di discussione ha riguardato il rapporto tra componente emotiva, componente razionale e dimensione sociale degli individui, analizzato da angolature diverse. Nel trattato La Politica, Aristotele definisce l'uomo un animal...

Play is an important and understudied class of phenomena that likely serves a critical role in the ontogeny and maintenance of fitness-enhancing behaviors. Many species exhibit little or no play. Among those animals that do play, some exhibit only very simple forms, while others engage in complex play both solitarily and socially. Likewise, some an...

The nature of emotions has been long debated in philosophy and science, especially with respect of whether intentions or, alternatively, emotions have a leading role in guiding social interactions and decision making. Behaviour has been used to determine the neurobiological mechanisms underlying the processing and expression of basic emotions. Cert...

In several primate species, including humans, embracing predicts the level of affiliation between subjects. To explore the functional meaning of embracing, we selected Theropithecus gelada as a model species. The basic level of the gelada society is the 1-male unit, and the integrity of the group is maintained by the strong bonds between females. I...

Yawn contagion, possibly a form of emotional contagion, occurs when a subject yawns in response to others' yawns. Yawn contagion has been reported in humans, chimpanzees, bonobos, geladas, wolves, and dogs. In these species, individuals form strong, long-term relationships and yawn contagion is highest between closely bonded individuals. This study...

Many animal species express, perceive and share emotions. These abilities have been favoured by natural selection because they allow subjects to respond to various situations in an appropriate way, thus facilitating survival and increasing fitness. The same-face/same-emotion phenomenon is at the basis of sharing feelings and emotions. Recent studie...

To manage a stressful stimulus animals react both behaviorally and physiologically to restore the homeostasis. In stable horses, a stressful stimulus can be represented by social separation, riding discomfort or the presence of novel objects in their environment. Although Heart Rate Variability is a common indicator of stress levels in horses, the...

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 victim...

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; full play face [FPF...

Play is one of the most difficult behaviors to quantify and for this reason, its study has had a very rocky history. Social play is ephemeral, difficult to distinguish from the other so-called serious behaviors, not so frequent (especially in sexually mature subjects), fast, and complex to describe. Due to its multifaceted nature, it has often been...

Birth attendance has been proposed as a distinguishing feature of humans (Homo sapiens) and it has been linked to the difficulty of the delivery process in our species. Here, we provide the first quantitative study based on video-recordings of the social dynamics around three births in captive bonobos (Pan paniscus), human closest living relative a...

Given that the cognitive and affective processes underlying empathy do not fossilize, studies of the empathic capacities of nonhuman primates provide us with a critical window through which we can explore the evolutionary origins of human empathy. Specifically, the comparative method provides an opportunity to determine which features of empathy ar...

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 affiliation and...

Dataset of gorillas and chimpanzees including for each individual age categories (ad = adult; subad = subadult; j = juvenile; inf = infant), age in months. (XLSX)

Dataset of gorillas and chimpanzees including for each individual grooming and contact sitting hourly frequencies and the hourly frequency of the grooming and contact sitting normalized on the number of potential partners. (XLS)

Dataset of gorillas and chimpanzees including play hourly frequency normalized on the number of the potential play partners and age class of individuals (a = adult; j = juvenile; i = infant). (XLSX)

Dataset of gorillas and chimpanzees including the number of supported, not supported, total conflicts and Agonistic Support Index (per individual) calculated as follows: (number of supported conflict − number of not supported conflict)/total conflicts. (XLS)

Dataset of gorillas and chimpanzees including the Polyadic Play Index for each subject included in the study. (XLSX)

Dataset of gorilla and chimpanzee dyads including the mean value of Play Asimmetry Index (mean PAI) and absolute value of mean PAI (abs mean PAI) for each dyads. (XLSX)