Animals compete for various resources in the race for survival and reproduction. Territoriality is a common strategy for dealing with competition, and defending resources like food, shelter and mates from conspecifics improves an individual’s fitness.
Much is known about territoriality in taxa such as birds and mammals, with studies mainly focused on males. Studies on taxa such as reptiles are fewer and across taxa, even fewer on sex differences. To gain a better understanding of sex differences in territoriality, I plan to study the less-studied reptilian system, the Indian Rock Agama (Psammophilus dorsalis), which is a tropical lizard found in peninsular India.
Males and females are likely to differ in the kind of resources they require in a territory, and that would influence their choice of territory. So, in the first chapter of my thesis, I will study the factors affecting sex differences in territory choice in Psammophilus dorsalis. For this, I propose to take a two-pronged approach, drawing insights from historical data from long-term observations, as well as conducting a detailed field study.
Individuals may differ in their competitive ability to defend a territory due to differences in morphological and behavioural traits. The costs and benefits of these traits are likely to differ between males and females, given the differences in their life histories. So I will examine the traits involved in territorial behaviour of males and females in the second chapter. This will involve studying the sex-differences in traits which are advantageous in acquiring and maintaining territories.
A key trait linked to competition for resources that affects the outcome of territorial interactions is dispersal. A resident and an immigrant are likely to experience competition for territories differently, which may be an important factor influencing the dynamics of territoriality in the species. So, in the third chapter, using a molecular genetic approach using microsatellite data, we will determine relatedness patterns to infer patterns of sex-biased dispersal, if present, in this species. I will also test the implications of these dispersal patterns for dynamics of territoriality in males and females.
Overall, this thesis aims to understand how sex differences influence the dynamics of territoriality in a lesser studied reptilian system.