Factors driving sexual dimorphism and colour variability in the Achala Copper Lizard ( Pristidactylus achalensis ), an endemic species to the highland mountains in central Argentina

CHIARAVIGLIO, M.; NARETTO, S.

CANADIAN JOURNAL OF ZOOLOGY

NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS

Lugar: Otawa; Año: 2020 vol. 98 p. 377 - 389

0008-4301

The intensity of mating competition varies according to the temporal and spatial distribution of individuals. Measuringsexual dimorphism over time and interpreting the association between individuals is therefore important if we aim tounderstand how sexual traits are influenced. We examined sex differences in the Achala Copper Lizard (Pristidactylus achalensis(Gallardo, 1964)), an endemic species from the highest part of mountains of central Argentina. Over 4 years, we exploredsex-specific variation in body size, head size, interlimb length, and body colouration. Furthermore, we evaluated how these traitsvaried temporally, and we also explored whether the spatial distribution of individuals is explained by variation in these traits.We found that P. achalensis is a species with sexual dimorphism in multiple characters, including body size, head size, andcolouration. Interestingly, some traits related to mating, such as head width, show a temporal variability in both sexes, whereasother traits, such as colouration, varies seasonally only in males. Our results underline the intriguing possibility of seasonalmorphological changes related to mating, and more broadly that sex differences are influenced by sexual selection pressuresmediated by temporal variation in mate competition.