The functional significance of colour polymorphism in the European common wall lizard (Podarcis muralis)
Colour polymorphisms, the coexistence of two or more colour morphs of a species within a population, have long fascinated evolutionary biologists interested in the mechanisms generating and maintaining phenotypic variation in nature. The functional significance of colour polymorphisms (i.e. their adaptive value) is often linked to the selective mechanisms responsible for their maintenance over time. In lizards, the hypothesis that colour morphs may reflect alternative reproductive strategies involving differential sociosexual behaviour and/or alternative reproductive strategies has come to dominate the field. Wall lizards (family Lacertidae, genus Podarcis), with several geographically dist…