Personality along the boldness-shyness axis in Psammophilus dorsalis

Abstract

Studies of personality, consistent behavioural differences between individuals, in animal behaviour reflect a paradigm shift in our understanding from the classical view of animals behaving optimally at all times. A wide range of studies in the past decade have described the existence of personality in animals across varied taxa. Nevertheless, studies measuring personality in wild populations, under their natural ecological and social contexts have been rather scarce. In addition, few empirical studies address the underlying drivers which can maintain personality, lesser so in the wild. As part of this thesis, I looked at the influence of state variables on personality using a novel study system the sexually dimorphic rock agama, Psammophilus dorsalis. I tagged and measured wild lizards and repeatedly assayed their response to a simulated threat within their natural home ranges and over a large part of their breeding lifespan. My study found substantial consistency in inter-individual differences in risk-taking, both in the short term, and over long term encompassing a large part of their breeding lifespan. Of all state-variables, sex and body condition seemed to be the most significant variables predicting differences in average risk-taking, but most of the measured state-variables were only weakly related to personality. The existence of clear personality variation in this wild lizard population, detectable even under typically variable and complex ecological and social conditions, opens a plethora of interesting opportunities to gain a better understanding of the adaptive role of personality in animal ecology.