Research Director at CNRS
List of publications: Link to research gate
Address: Ethologie cognitive et sociale, CNRS, Délégation Alsace, 23 rue du loess, 67037 Strasbourg, France
email: bernard.thierry@cnrs.fr phone: (33) 388 107 458
Profile
1982, MD Thesis, Veterinary Medicine, Ecole Nationale Vétérinaire, Toulouse
1984, PhD Thesis, Ethology, Université Louis Pasteur, Strasbourg
1997, Research Direction Habilitation, Ethology, Université Louis Pasteur, Strasbourg
Research topics
- Social cognition and group movements in mammals: how information transmission and recruitment processes lead to collective performances in mammals
- Comparative study of primate societies: how adaptive function trades off against epigenetic constraints in the social organization of macaques
Current projects
- Reproductive strategies in a tolerant species of macaque: how adult males manage mating competition, stress, and rank reversals in Tonkean macaques
(Collaborators: A. De Marco, H. Gachot, J. Duboscq)
- Comparative study of communication in four macaque species: is there a link between complexity of vocal signals and degree of social inequality?
(collaborators: N. Rebout, A. De Marco, R. Cozzolino, A. Sanna, L. Sterck, J. Micheletta, A. Lemasson)
Recent publications
Broihanne M.H., Romain A., Call J., Thierry B., Wascher C., De Marco A., Verrier D., Dufour V., 2019. Monkeys (Sapajus apella and Macaca tonkeana) and great apes (Gorilla gorilla, Pongo pygmaeus, Pan paniscus and Pan troglodytes) play for the highest bid. Journal of Comparative Psychology 133: 301-312.
De Marco A., Rebout N., Massiot É., Sanna A., Sterck E.H.M., Langermans J.A.M., Cozzolino R., Thierry B. & Lemasson A., 2019. Differential patterns of vocal similarity in tolerant and intolerant macaques. Behaviour 156: 1209-1233.
Rebout N., De Marco A., Lone J.C., Sanna A., Cozzolino R., Micheletta J., Sterck E.H.M., Langermans J.A.M., Lemasson A. & Thierry B., 2020. Tolerant and intolerant macaques show different levels of structural complexity in their vocal communication. Proceedings of the Royal Society B 287: 20200439.
De Marco A., Cozzolino R. & Thierry B., 2020. Responses to a dead companion in a captive group of tufted capuchins (Sapajus apella). Primates 133: 301-312.
Thierry B., Deneubourg J.L. & Poulin N., 2020. Modelling persistence over generations in biological and cultural evolution based on differential paces of change. BioSystems 196 : 104139.
Highlights
Rebout N., De Marco A., Lone J.C., Sanna A., Cozzolino R., Micheletta J., Sterck E.H.M., Langermans J.A.M., Lemasson A. & Thierry B., 2020. Tolerant and intolerant macaques show different levels of structural complexity in their vocal communication. Proceedings of the Royal Society B 287: 20200439.
We tested the social complexity hypothesis which posits that animals living in complex social environments should use complex communication systems. We focused on two components of vocal complexity: diversity (number of categories of calls) and flexibility (degree of gradation between categories of calls). We compared the acoustic structure of vocal signals in groups of macaques belonging to four species with varying levels of uncertainty (i.e. complexity) in social tolerance (the higher the degree of tolerance, the higher the degree of uncertainty): two intolerant species, Japanese and rhesus macaques, and two tolerant species, Tonkean and crested macaques. We recorded the vocalizations emitted by adult females in affiliative, agonistic and neutral contexts. We analysed several acoustic variables: call duration, entropy, time and frequency energy quantiles. The results showed that tolerant macaques displayed higher levels of vocal diversity and flexibility than intolerant macaques in situations with a greater number of options and consequences, i.e. in agonistic and affiliative contexts. We found no significant differences between tolerant and intolerant macaques in the neutral context where individuals are not directly involved in social interaction. This shows that species experiencing more uncertain social interactions displayed greater vocal diversity and flexibility, which supports the social complexity hypothesis.
De Marco A., Cozzolino R. & Thierry B., 2020. Responses to a dead companion in a captive group of tufted capuchins (Sapajus apella). Primates 133: 301-312.
doi: 10.1007/s10329-019-00743-y
The observation of specific reactions by animals to dead conspecifics raises questions about their capacity to understand death. We describe the behavior of a captive group of tufted capuchins in the hours following the death of an adult female. The behavior of 12 subjects was recorded over a 5-h period. Most group members displayed exploratory behaviors toward the corpse, peering at it, smelling, touching, lifting or pulling it at least once. Interactions with the corpse were particularly frequent in the first hour, then decreased in the following hours. The relatives of the deceased female were the most involved individuals, and her daughter spent more time near her body than the other members of the group. Rates of interaction with the body were especially high in subadult individuals. Most of the behaviors directed to the body of the deceased individual appeared to be investigative.
Thierry B., Deneubourg J.L. & Poulin N., 2020. Modelling persistence over generations in biological and cultural evolution based on differential paces of change. BioSystems 196 : 104139.
doi: 10.1016/j.biosystems.2020.104189
Paces of change are faster in cultural evolution than in biological evolution due to different levels of stability in information storage. This study develops mathematical models to investigate the consequences of differential mutation rates on the ability of groups of information units to survive over many generations. We examined the ability of groups composed of connected units to live on despite the occurrence of deleterious mutations that occur at probabilities ranging from 10⁻¹ to 10⁻⁶. It appears that the degree of connection between units should be high enough for groups to persist across generations, but this alone did not ensure their survival; when groups of units were limited in size and subjected to high mutation rates, they did not survive for very long. By contrast, a significant proportion of groups were able to survive numerous generations if mutation rates were low and/or group size was large. The results revealed that the mean number of surviving generations was minimized for certain sizes of groups. When allowing information units to duplicate at each generation, simulation showed that a great number of groups avoided extinction even when mutating at the rate of cultural change if the initial group size was large and the duplication rate was high enough to counteract the consequences of environmental perturbations. The modelling described in this study sets out the conditions under which groups of units can survive along generations. It should serve as a basis for further investigations about the links between processes of biological and cultural changes.
Equipe éthologie cognitive et sociale 