Reut Berger-Tal

Costs and Benefits of Inbred Sociality

One of the means to evolution of a cooperative group is by elimination of dispersal from the natal nest, and establishment of a ‘family’ group. Reduced dispersal, however, has implications on the genetic structure and the genetic diversity within the nest, and at the species level. Empirical data on the forces shaping sociality formed by means of limited dispersal is scarce. In my PhD I explore the costs and benefits associated with sociality formed by limited dispersal. I measure the possible costs of inbreeding and the benefits of cooperation by means of kin selection. Social spiders are a well suited system to explore these questions as cooperation was evolved and maintained by means of limited dispersal. I employe complementary methods such as: field observations, controlled lab experiments and chemical profiling, in the social spider Stegodyphus dumicola (Eresidae) by looking at: (i) costs of inbreeding, (ii) benefits of cooperating with kin, (iii) factors that shape dispersal and (iv) measuring mechanisms of possible kin discrimination.