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.
Zottl M, Thorley J, Gaynor D, Bennett NC, Clutton-Brock T. (2016) Variation in growth of Damaraland mole-rats is explained
by competition rather than by functional specialization for different tasks. Biol. Lett. 12: 20160820. http://dx.doi.org/10.1098/rsbl.2016.0820
Thorley J & Clutton-Brock T (2016) Kalahari vulture declines, through the eyes of meerkats. Ostrich: Journal of African Ornithology. http://dx.doi.org/10.2989/00306525.2016.1257516
Thorley J & Lord AM (2015) Laying date is a plastic and repeatable trait in a population of Blue Tits Cyanistes caeruleus. Ardea 103: 69–78. doi:10.5253/arde.v103i1.a7