Workshop SNAAS (Social Network Analysis in Animal Societies)

Experimental design of information transmission and collective decision-making

Non programmé

20m

Auditorium (Collège Doctoral Européen, Strasbourg)

Présentation orale

Orateur

Dr Richard Bon (Centre de recherches sur la Cognition Animale, CNRS-UPS, Toulouse)

Description

When an individual leaves its group and initiate a collective move, individual mechanisms are required to maintain group cohesion. Numerous studies have revealed that collective motions depend on interactions between individuals and have proposed models allowing reproducing observed collective patterns. However most of these studies infer the individual behaviour from the collective observations. Recently, a social model simulating the following behaviour in sheep (Ovis aries) was formalized thanks to experimental data collected at the individual level. It reveals that after an initiation in small groups, the individual following probability depends both on the number of conspecifics already departed and the number of non-departed individuals. This model relies on the hypothesis that in small groups, all individuals can monitor each other and that their response is independent from their positions. Here, we applied the protocol used previously to build the model but with increased group sizes and applied the social model with the results we obtained experimentally. The social model is pertinent in groups of 8 and 16 individuals, but not in groups of 32. We propose that in large groups, the information propagates and we show that the decision making to follow depends on individuals’ position relatively to the initiator.