Morph-specific pattern of aggression throughout the season in Podarcis muralis

The persistence of colour polymorphism (CP) within a given population is generally associated with the coexistence of alternative reproductive strategies, each one involving specific trade-offs among behavioural, morphological, physiological, and other life history. Trade-offs involving immune system are of particular interest, since the ability of dealing with parasites and diseases has severe consequences on the fitness individuals may achieve, but also entails substantial costs for them. T-level fosters a strong motivation to defend territories against rivals (i.e. increasing movements, activity, and aggressive display) and increases mating. At the same time, high T-level can decrease immune functions, favours parasite infections, stimulates risky behaviours, and thus diminishes survival, according Immunocompetence Handicap Hypothesis (ICHH), and there is no way to maximize stamina and aggressive behaviours at once. Common wall lizard (Podarcis muralis) showing CP in three main color (yellow, white and red) and a morph specific pattern for both immunocompetence and seasonal variation of T-levels, where the former show low stamina with high plasma T-levels and the following high stamina with low intra-sexual competitive ability. We hypothesised the presence of 2 strategies: one from yellow-morph and another from white/red-morph. Thus we tested the aggressive response to conspecifics of yellow and whitemorph using a mirror inserted into the own setting box, throughout the breeding season (128 experiments). All lizard was tested after a period of acclimatization. Results demonstrated the yellow males was more aggressive in the early bird season and with a decrease towards the end, whereas white males show an opposite pattern