Yvan I. Russell: Sociality in great apes: studies of reputation, food sharing, and grooming
- Datum: 07.10.2016
- Uhrzeit: 11:00 - 12:00
- Vortragende(r): Yvan I. Russell von der Middlesex University, London, GB
- Mehr Informationen über den Vortragenden: https://www.mdx.ac.uk/about-us/our-people/staff-directory/profile/russell-yvan
- Ort: MPI Plön
- Raum: Hörsaal
- Gastgeber: Dirk Semmann
Zusammenfassung (auf Englisch):
This talk will proceed in two parts. The first is an
eavesdropping experiment in four great ape species. Inspired by previous
studies in “image scoring” (agent-based models/behavioural economics)
which showed the importance of reputation in the evolution of
cooperation – this study sought to conduct an animal version of an image
scoring study. While unable to show the entire sequence of positive
indirect reciprocity (“A observes B help C, therefore A helps B”), the
focus was on the information gathering aspect (“A observed B feed C”)
and the self-interested inference (“therefore A will feed me”). We gave
the apes an opportunity to eavesdrop on interactions between human
actors whereupon a “nice” person gave grapes to person who begged for it
and a “nasty” person refused to give grapes. The dependent variable –
the apes’ expectation of which human (the nice or nasty) was more likely
to offer food later – were measured by time spent with either person
(who showed food but actually withheld it). Results showed that the Pan
species (chimpanzees, bonobos) showed a significant preference for the
nice person, whereas the gorillas and orangutans showed no preference.
The second part of this talk focuses on allogrooming in a captive
chimpanzee group. We investigated grooming reciprocity over different
time windows. We found that time-matching, when measured precisely,
occurs only during bouts of simultaneous grooming and that precise
matching deteriorates with delay. This implies that grooming
reciprocity, if calculated, is more of a short-term contract and in the
longer-term is based on an attenuated representation.