Life history trade-offs in co-operative breeders

Damaraland Mole-rats, Fukomys damarensis: 

The social mole-rats are physiological enigmas, as exemplified by their ability to withstand hypoxia, their resistance to cancer-like phenotypes, and their extraordinary longevity. Such characteristics have catapulted social mole-rats (largely naked mole-rats) into the limelight as model organisms in medicine. Yet, few studies have intensively studied individual mole-rats across their development in an ecologically relevant setting, which hinders our ability to draw meaningful inferences about life history covariation in mole-rats from an ecological perspective. Our lab is seeking to address this imbalance in longitundinally studying a large number of Damaraland mole-rat groups in artificial 'burrow' systems in the Kalahari. Using this system, I am examining how individual behaviour covaries with growth and ageing in Damaraland mole-rats, and therein examine the relative costs of reproduction or subordination. More broadly I am motivated by the association between sociality and longevity in mammals.

Meerkats, Suricata suricatta:

Co-operative breeders are an interesting case study for life history theory, with the apparent load-lightening effects of helpers granting reproductive individuals high levels of fecundity across unusually long lives. Yet, the high reproductive success of a select few females and males results in intense competition for breeding rights in both sexes. Through my meerkat work, I investigate the relative influence of helping versus competition in shaping individual life history trajectories, with particular emphasis upon sex differences in rates of ageing.