Biology subjects

Keupp, S.

Publications and source records attributed to Keupp, S..

3 recordsLinked to original sources

bioRxiv2025

Tonkean macaques do not prefer the helper or the hinderer in the hill paradigm

Evaluating others prosocial tendencies can benefit individuals by allowing them to interact with prosocial individuals and avoid antisocial ones. The ontogeny of humans strong prosocial preference has been widely investigated using the hill paradigm. Childrens preference for helper over hinderer agents was measured after they watched a scene in which the helper agent pushed a climber up a hill while the hinderer agent pushed the climber down the hill. Bonobos tested with the hill paradigm preferred the hinderer over the helper, contrasting previous findings for other nonhuman primates. We tested Tonkean macaques (Macaca tonkeana) using the same procedure as the one used with bonobos to see whether they would also exhibit a hinderer preference. Subjects did not prefer the helper over the hinderer (or vice versa). The low attentional level observed in our subjects suggests a lack of interest in the video stimuli. This finding relates to more general questions regarding how animals perceive abstract animated onscreen stimuli and the relevance of the hill paradigm in investigating prosocial preferences. Studies using various experimental paradigms with conspecifics or human actors as social agents are needed to investigate further the social evaluation of prosocial behaviours in Tonkean macaques, bonobos, and other primates.

animal behavior and cognition↗

bioRxiv2024

Choose your partner: Social evaluation of skilfulness at cooperative co-action tasks in Tonkean macaques (Macaca tonkeana)

Social evaluation - inferring individual characteristics of others from their past behaviours - is an adaptive strategy that helps to inform social decisions. However, how nonhuman primates form and use impressions about others to select their social partners strategically is still unclear. In this study, we investigated whether Tonkean macaques, Macaca tonkeana, can spontaneously use information, acquired by observation, to choose the optimal partners for cooperation in two co-action tasks from the same domain. The subjects (N=5) did not prefer to cooperate with the skilful partner compared to the unskilled partner, irrespective of the task or how much attention they paid to the partners actions solving a solo version of one task prior to the test. The probability of optimal choices did not increase through trials either, indicating no learning by experience with the partners across the 16 test trials. Our results contradict findings of previous studies that tested monkeys in different domains of competence and contexts, and thus encourage further investigation on monkeys social evaluation abilities. Our experimental design presents a promising way to investigate different contexts, the inter-individual differences, the different types of social information involved, and the cognitive mechanisms underlying social evaluation and partner selectivity in nonhuman primates.

animal behavior and cognition↗

bioRxiv2024

Increased female competition for males with enhanced foraging skills in Guinea baboons

Recognizing skillful group members is crucial for making optimal social choices. Whether and how nonhuman animals attribute skill to others is still debated. Using a lever-operated food box, we enhanced the foraging skill of a single male (the specialist) in one zoo housed and two wild groups of Guinea baboon (Papio papio). We measured group members behav-ioral responses before, during, and after our manipulation to reveal whether they focused on the outcome of the males actions or changed their assessment of his long-term value. During the manipulation, females in the specialists unit, but not the wider group, competed over ac-cess to the specialist - increasing their grooming of him tenfold and aggression near him four-fold. Both behaviors were predicted by the amount each female ate from the food box and re-turned to baseline within two weeks of its removal. This behavioral pattern supports an out-come-based assessment where females responded to male-provided benefits (utility) rather than attributing competence (value). TeaserGuinea baboon females monopolize males in relation to their current perceived utility.

animal behavior and cognition↗