I am interested sex allocation theory and how it might be applied to a cooperative breeder, the meerkat (Suricata suricatta). Adaptive offspring sex ratio variation is seen throughout the animal kingdom, and has led to the development of a number of influential theories – for example, the Trivers-Willard hypothesis, which suggests that individuals may adjust the sex ratio of their offspring according to their environmental conditions and fitness.

The meerkat fits the basic assumptions of this model, indicating that there is the potential for facultative sex ratio adjustment in this species. The meerkat’s complex life history and social structure introduces a host of factors that will affect the relative costs and benefits of producing male and female offspring at any point in the female’s life history trajectory, making the study of sex allocation in this species complicated – but fascinating!

Variation in litter sex ratio also varies the level of androgen exposure offspring experience in utero. How will this affect their growth and development? I am particularly interested in how such variation in early experience could influence key tendencies in the meerkat behavioural phenotype – towards cooperation, or aggression.

The central questions of my PhD are:
•  Is there evidence for adaptive sex ratio bias in the meerkat?
•  Is one sex more costly to produce?
• What are the effects of sex ratio bias on offspring in terms of morphology, behaviour, and fitness?

Answering these questions will involve detailed analysis of the long-term database, hormonal analysis, and behavioural observation and experiments at the Kalahari Meerkat Project.