Welcome to the Alpine Marmot Project
Assistant lecturer – Université Claude-Bernard – Lyon1
tel. : +33(0)4 72 43 35 84
fax : +33(0)4 72 43 13 88
UMR CNRS 5558 – LBBE
Biométrie et Biologie Évolutive
UCB Lyon 1 – Bât. Grégor Mendel
43 bd du 11 novembre 1918
69622 VILLEURBANNE cedex
Senescence is defined as the decline of an individual’s performance with age. Over the past two decades, a large number of empirical studies have provided evidence that the senescence phenomenon is widespread in wild animal populations.
In species living in social groups (often family), non-breeding adults help dominants to raise young. In 1992, Crick proposed that the dominant could benefit from the help of subordinates and thus could reduce their own investment in reproduction. The cost of reproduction being reduced, one can expect that the presence of helpers affects the pattern of senescence. So the social context can potentially have an influence on senescence either by removing, delaying or reducing its intensity. Nevertheless, there has been very little study on the effect of sociality on the pattern of senescence.
My thesis project focuses on three questions:
1) Quantify the age of onset of senescence in survival and reproduction, and its intensity.
2) Evaluate the influence of social factors (composition of the social group and its variations) on the pattern of senescence.
3) Conduct a comparative study in order to identify differences in the pattern of senescence with the gradient of sociality.
French Ministry of Education and Research grant (2012 – 2014)
Berger V., Lemaître JF., Dupont P., Allainé D., Gaillard JM. and Cohas A. (2016) Age-specific survival in the socially monogamous alpine marmot (Marmota marmota): evidence of senescence. Journal of Mammalogy, XX: 1-9. pdf
Gaillard JM., Berger V., Clauss M., Duncan P., Muller D., Tidière M. & Lemaître JF. In Press. Does tooth wear allow predicting aging: a comparative study across large herbivores Experimental Gerontology.
Gaillard JM., Lemaître JF., Berger V., Bonenfant C., Devillard S., Douhard M., Gamelon M., Plard F. & Lebreton JD. In press. 85. Axes of variation in life histories. In Encyclopedia of Evolutionary Biology, RM Kliman (Ed.). Elsevier.
Berger V., Lemaître JF., Allainé D., Gaillard JM. and Cohas A. (2015) Early and adult social environments have independent effects on individual fitness in a social vertebrate. Proceedings of Royal Society B, 282:20151167. pdf
Berger V., Lemaître JF., Gaillard JM., Cohas A. (2015) How do animals optimize the size-number trade-off when aging? Insights from reproductive senescence patterns in marmots. Ecology, 96: 46-53. pdf
Lemaître JF., Berger V., Bonenfant C., Douhard M., Gamelon M., Plard F., Gaillard JM. (2015) Early-late life trade-offs and the evolution of ageing in the wild. Proceedings of Royal Society B, 282:20150209.
Berger V. (2015) Senescence and sociality in the Alpine marmots. European workshop on Alpine marmot. Gran Paradiso National Park. Valsavarenche, Italie, 17-18 October. Oral communication.
Berger V., Lemaître JF., Gaillard JM. & Cohas A. (2014) How do animals optimize the size–number trade-off when aging? Insights from reproductive senescence patterns in marmots. British Ecological Society in Lille, 9-12 December. Oral communication.
Berger V., Bonenfant C., Douhard M., Gaillard JM. & Plard F. (2013) Body mass trajectory of two roe deer (Capreolus capreolus) populations: the effect of sex. French Society for Animal Behavior Study. Dijon, 19-21 November. Oral communication.