Social Selection in the Wild

• Applicant: Dr. Francesca Santostefano
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions ; Sensory and Behavioural Biology
• Term: from 2017 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 391379137

In all animal species, individuals interact with each other throughout their lifetime: courtship, competition, communication, and cooperation all involve social interactions. The characteristics of conspecifics, including how they behave, have substantial consequences on an individual’s survival and reproduction. The effect of conspecifics on an individuals’ fitness is termed social selection. Despite recent interest by behavioural ecologists in the evolutionary consequences of individual behavioural variation (‘personality’), the role of behaviour as an agent of social selection has been so far overlooked and rarely tested empirically in the wild.This project aims to test in an ecologically relevant contest whether behaviours of conspecifics do indeed impose social selection. I will do so on a wild population of Eastern chipmunks (Tamias striatus), part of a large scale quantitative genetic study in a field site in Québec, Canada. This project will provide an empirical test of how an individual’s fitness is shaped by the behaviours of conspecifics. The study will make use of a long term dataset to which I will add my own data collection. I will measure key behaviours (docility, exploration) and proxies of fitness (lifetime and annual reproductive success, adult annual survival), as well as map the spatial network of territories and social network of interactions between individuals. With molecular tools and paternity assignments methods (microsatellite analyses) I will estimate the relatedness between individuals in the population and build its pedigree. I will apply quantitative genetic tools, survival and spatial analyses to estimate the effect of the social environment (i.e. genotypes/phenotypes of conspecifics) on fitness, and the strength of such effects. Because the pattern of social interactions (who interacts with whom) is usually determined by the spatial distribution of individuals in the environment, I will also investigate how different behavioural phenotypes are distributed in space, i.e. if individuals choose their neighbours (disassortatively or assortatively). Findings from this project will show the importance of interactions among conspecifics as an agent of selection, and improve our understanding of social evolution in the wild.

• DFG Programme: Research Fellowships
• International Connection: Canada
• Host: Professor Dr. Denis Reale