Damaraland mole-rats are a cooperative or eusocial species living in southern Africa. They live in groups of up to 40 individuals with one female monopolising reproduction and supressing all other females of the group. The colonies forage by cooperatively building extensive burrows that provide access to tubers and roots which are the sole source of food and water. All colony members contribute to establishing one or several communal food stores and provide care (huddling, retrieving) to offspring born to the single reproductive female. Damaraland mole-rat life-histories appear to be broadly similar to those of naked mole-rats though Damaralands more commonly outbreed and males are larger than females.
The aim of the project is to provide an integrated understanding of social evolution and organisation in mammalian societies. In particular, we aim to understand the causes and consequences of individual differences in cooperative behaviour and growth and to determine whether they represent alternative strategies which maximise direct and indirect components of fitness or whether they are a non-adaptive consequence of environmental or social constraints. To do this we are investigating the effects of condition and maternal hormones on behaviour, growth and reproductive success in captive and wild Damaraland mole-rats. We are also investigating the effects of variation in the size, timing and sex ratio of litters on development and cooperative behaviour. Finally, we are exploring the social and ecological factors affecting rates of aging in breeders and helpers.