Genetic and environmental drivers of colour and pattern in the Australian jacky dragon (Amphibolurus muricatus)

Abstract

The underlying drivers of variation in the colouration (colour and pattern) of animals can be genetic, non‐genetic, or more likely, a combination of both. Understanding the role of heritable genetic elements, as well as non‐genetic factors such as age, habitat or temperature, in shaping colouration can provide insight into the evolution and function of these traits, as well as the speed of response to changing environments. This project examined the genetic and non‐genetic drivers of continuous variation in colouration in a lizard, the jacky dragon (Amphibolurus muricatus). We leveraged a large captive experiment that manipulated parental and offspring thermal environment to simultaneously estimate the genetic and non‐genetic drivers of variation in colouration. We found that the overall brightness, the elongation of the longitudinal stripes on the dorsum and the contrast between light and dark patches of the pattern were all heritable. Colouration varied according to the age of the hatchling; however, the thermal environment of neither the parents nor offspring contributed significantly to colouration. It appears that developmental plasticity and maternal effects associated with temperature are not important drivers of variation in our measures of colouration.

Population variation in signaling behavior and contest outcome in the jacky dragon

“…Overall, factors such as the vegetation structure and presence of predators seem to influence the signaling behavior of a population (Barquero, 2014; Ramos & Peters, 2017). Although the species relies on its cryptic coloration to avoid predators (Raynal et al, 2022), the visual displays have shown to be highly conspicuous (Woo, 2021). The signaling behavior of the species has been extensively studied and distinctive aggressive and submissive displays have been identified (Carpenter et al, 1970; Peters & Ord, 2003; Watt & Joss, 2003; Van Dyk & Evans, 2007; Barquero et al, 2015; Ramos & Peters, 2017).…”