The evolution of elaborate phenotypic traits, which are widespread in the animal kingdom, is usually attributed to sexual selection. However, natural selection can impose constraints on the degree of elaboration of such traits. Therefore, animal signals reflect a balance between the two forces of natural and sexual selection. I am interested in understanding the relative strength of these forces in maintenance of a complex signal type: dynamic colour change. Males of the peninsular rock agama (*Psammophilus dorsalis*) exhibit rapid dynamic colour changes on their lateral and dorsal body regions during social interactions. The costs, benefits, and adaptive significance of this dynamic colour change is yet unknown.
The main objectives of my study are to: (1) examine the relative importance of different components of the dynamic colour signal by assessing behavioural responses of males and females to each signal component independently and together; (2) determine the information content of the multicomponent colour signal by examining whether the magnitude of colour change is associated with key measures of health and immunity, and (3) quantify the effect of ecological variables such as microhabitat, social intensity, and predation intensity on visual signalling.