Prosociality in a despotic society

Prosociality is the intent to improve others’ well-being. Existing hypotheses postulate that enhanced social tolerance and inter-individual dependence may facilitate prosocial preferences, which may favor the evolution of altruism. While most studies are restricted to “tolerant” (cooperatively breeding and self-domesticated) species, despotic societies provide an alternative opportunity to investigate prosociality due to nepotism and ample inter-individual dependencies. Japanese macaques live in hierarchical matrilineal societies, with strong kin bonds. Besides, tolerance among non-kin may persist through reciprocity. Using a group service food-provision paradigm, we found prosocial preferences in a semi free-ranging group of Japanese macaques. The extent of provisioning was at levels comparable to tolerant species. Dyadic tolerance predicted the likelihood and magnitude of provisioning, while kinship predicted the magnitude. We emphasize the role of a complex socio-ecology fostering individual prosocial tendencies through kinship and tolerance. These findings necessitate a framework including different forms of interdependence beyond the generally tolerant species

A novel methodological approach for group classification during fission of a semi-free-ranging group of Japanese macaques (Macaca fuscata)

The self-initiated split of a social group, known as fission, is a challenge faced by many group-living animals. The study of group fission and the social restructuring process in real time provides insights into the mechanism of this biologically important process. Previous studies on fission in Japanese macaques (Macaca fuscata) assigned individuals to newly reorganized groups mainly using behavioral observations and group attendance records based on periods before or after fission itself. Here, we present a novel framework for group classification during the process of fission that uses quantifiable behavioral variables and statistical analyses. The framework was tested on a group fission process at Affenberg Landskron (Austria), a park that housed around 160 semi-free-ranging Japanese macaques. The behavioral data were collected for 26 days during fission. We analyzed three behavioral developments recurrent in fissions in Japanese macaques, that is, independence of behavior, participation in group movements, and separation of nomadic ranges. These analyses were combined to assign individuals to different groups. Our study resulted in one main group (N = 33), one subgroup (N = 36) and 56 individuals whose group membership was still undefined. The demographic characteristics of these newly formed groups were comparable with those of fissioned groups in wild populations. Furthermore, we found that these newly forming groups showed early social dynamics of fission five months before group level movements, that is: grouping based on spatial proximity and spatial withdrawal of the subgroup to the periphery. These results underline the validity of our novel framework to study social dynamics in Japanese macaques during the process of fission. It represents an important addition to existing methods, and we recommend testing its scope in other primate societies

Studying the Evolution of Cooperation and Prosociality in Birds

The social brain hypothesis (Humphrey, 1976) poses that the intricacies of social life may have been a significant selection pressure for the evolution of mind. This evolution may act on competition between group members and strategies to outcompete others (Machiavellian intelligence hypothesis: Byrne & Whiten, 1988), or on cooperative tendencies between group-members that provide benefits that cannot be reached by a single individual (Vygotskian intelligence hypothesis: Moll & Tomasello, 2007). The latter hypothesis, however, creates an evolutionary conundrum, as cooperation is prone to free-riders, and with defection being an evolutionary stable system, the occurrence and complexity of cooperation in humans and other animals remains a puzzle. Several theoretical advances have been made to explain the evolution of cooperation nonetheless, with kin-selection (Hamilton, 1964) and reciprocal altruism (Trivers, 1971) being the most prominent ones. However, the proximate mechanisms that foster the strategies proposed in the Vygotskian intelligence hypothesis and the required cognition in nonhuman animals, remain a hotly debated topic (see Massen et al., 2019)

Why contagious yawning does not (yet) equate to empathy

Various studies and researchers have proposed a link between contagious yawning and empathy, yet the conceptual basis for the proposed connection is not clear and deserves critical evaluation. Therefore, we systematically examined the available empirical evidence addressing this association; i.e., a critical review of studies on inter-individual differences in contagion and self-reported values of empathy, differences in contagion based on familiarity or sex, and differences in contagion among individuals with psychological disorders, as well as developmental research, and brain imaging and neurophysiological studies. In doing so, we reveal a pattern of inconsistent and inconclusive evidence regarding the connection between contagious yawning and empathy. Furthermore, we identify study limitations and confounding variables, such as visual attention and social inhibition. Future research examining links between contagious yawning and empathy requires more rigorous investigation involving objective measurements to explicitly test for this connection

Azure-winged magpies’ decisions to share food are contingent on the presence or absence of food for the recipient

Helping others is a key feature of human behavior. However, recent studies render this feature not uniquely human, and describe discoveries of prosocial behavior in non-human primates, other social mammals, and most recently in some bird species. Nevertheless, the cognitive underpinnings of this prosociality; i.e., whether animals take others’ need for help into account, often remain obscured. In this study, we take a first step in investigating prosociality in azure-winged magpies by presenting them with the opportunity to share highly desired food with their conspecifics i) in a situation in which these conspecifics had no such food, ii) in a situation in which they too had access to that highly desired food, and iii) in an open, base-line, situation where all had equal access to the same food and could move around freely. We find that azure-winged magpies regularly share high-value food items, preferably with, but not restricted to, members of the opposite sex. Most notably, we find that these birds, and specifically the females, seem to differentiate between whether others have food or do not have food, and subsequently cater to that lack. Begging calls by those without food seem to function as cues that elicit the food-sharing, but the response to that begging is condition-dependent. Moreover, analyses on a restricted dataset that excluded those events in which there was begging showed exactly the same patterns, raising the possibility that the azure-winged magpies might truly notice when others have access to fewer resources (even in the absence of vocal cues). This sharing behavior could indicate a high level of social awareness and prosociality that should be further investigated. Further studies are needed to establish the order of intentionality at play in this system, and whether azure-winged magpies might be able to attribute desire states to their conspecifics

An observational investigation of behavioural contagion in common marmosets (Callithrix jacchus): indications for contagious scent-marking.

Behavioural contagion is suggested to promote group coordination that may facilitate activity transitions, increased vigilance and state matching. Apart from contagious yawning, however, very little attention has been given to this phenomenon, and studies on contagious yawning in primates have so far only focused on Old World monkeys and apes. Here we studied behavioural contagion in common marmosets, a species for which group coordination and vigilance are paramount. In particular, we investigated the contagiousness of yawning, stretching, scratching, tongue protrusion, gnawing and scent-marking. We coded these behaviours from 14 adult marmosets, from two different social groups. During testing sessions, animals were separated into groups of four individuals for 20-minute observation periods, across three distinct diurnal time points (morning, midday and afternoon) to test for circadian patterns. We observed almost no yawning (0.12 yawns / hour) and very little stretching behaviour. For all other behaviours, which were more common, we found several temporal and inter-individual differences (i.e., sex, age, dominance status) predictive of these responses. Moreover, we found that gnawing and scent-marking, that almost always co-occurred as a fixed-action pattern, were highly temporally clustered within observation sessions. We discuss the relative absence of yawning in marmosets as well as the possible function of contagious scent-marking, and provide suggestions for future research into the proximate and ultimate functions of these behaviours in marmosets

Gender bias in the allocation of student grants

Multiple studies have shown that women’s likelihood of receiving research funding is lower than that of their male colleagues. Thus far, all research on this gender gap in academia has focused on post-PhD academics, making it difficult to discern whether the female disadvantages in number of publications, previous grants, maternity leave, and h-indexes are at the root of the gender gap in received funding, or whether it is due to a more fundamental gender bias in academia. Therefore, we investigated whether female university students are already disadvantaged in receiving their first grant in their scientific career. We analysed data on applications (N = 2651) from 1995 to 2018 to the Leiden University International Study Fund (LISF), a fund dedicated to support students to study or conduct research abroad. We found that men and women applied equally often to the LISF. However, women had a lower success rate, which seemed to only get worse over recent years. Furthermore, male and female applications were assessed to be equal in quality when gender-related information was removed from them. The current study demonstrates that the factors that were assumed to contribute the most to the gender gap in more senior academics (e.g. previous grants, h-index) do not explain it fully: even when those factors do not yet play a role, such as in our student sample, women were found to have lower success rates than men. This underscores the importance of attacking gender biases at its roots