| UV signalling has now been shown to occur in many taxa, including ... lizards (e.g. Whiting et al. 2006), amphibians (e.g. Secondi et al. 2012), ...
While current evidence seems to indicate that, in lacertids, UV signals primarily evolved to resolve male-male conficts and avoid contest escalation (Bajer et al. 2011; Pérez i de Lanuza et al. 2014; Martin et al. 2015a, 2016), UV coloration may also play a role in female mate choice in some species (Bajer et al. 2010; Badiane et al. 2020). Wall lizards from the genus Podarcis comprise 24 species and the males of most of these species have conspicuous colour patches on some of their outer-ventral scales (OVS). These colour patches appear blue to the human eye but are in fact UV-refecting and therefore best described as UV-blue. In the common wall lizard (Podarcis muralis), Pérez i de Lanuza et al. (2014) showed that the hue and UV chroma of the UV-blue patches are related to size-independent bite force (a proxy of male fghting ability in lizards, Huyghe et al. 2009) and body condition, respectively, suggesting condition dependence and a role in male-male interactions and contest behaviour. MacGregor et al. (2017) also found a relationship between the hue and UV chroma of the UV-blue patches and male reproductive success in two P. muralis lineages. Martin et al. (2015a) and Names et al. (2019) found that manipulating the refectance and size of UV-blue patches afected male agonistic interactions. Finally, Abalos et al. (2016) reported that natural variation in the size and refectance of the UV-blue patches does not predict the outcome of laboratory-staged contests between size-matched males, and proposed that the UV-blue patches may be important during the early stages of contests during which rival assessment takes place. Taken together, these results suggest that the UV-blue patches may play a role in male-male signalling, but the evidence for their role as signals of fghting ability remains equivocal. |
