Meeting Abstract

37.4  Thursday, Jan. 5  The growing dewlap - comparing growth trajectories in sexually and naturally selected traits in male and female Anolis baracoae VANHOOYDONCK, B*; HERREL, A; University of Antwerp, Antwerop, Belgium; National Museum of Natural History, Paris, France bieke.vanhooydonck@ua.ac.be

Anolis lizards are characterized by an extendable throat fan, called a dewlap. Dewlaps vary greatly in size, shape, pattern and colour among species and among populations. In addition, the degree of sexual dimorphism in dewlap traits varies, with some species being highly dimorphic whereas in some, males and females do not differ greatly. The dewlap has been suggested to serve multiple purposes, including courtship, territorial interactions, species recognition and predator deterrence. In this study, we aim to understand how the dewlap grows and whether growth differs between the sexes in Anolis baracoae, a crown-giant from Cuba. In addition, we compare the growth trajectory of the dewlap with other aspects of morphology (i.e. SVL, head and limb dimensions) typically considered to be relevant in a natural selection context. To do so, we raised 23 A. baracoae individuals (Nmales = 14, Nfemales = 9) under identical conditions in the lab. Dewlap size, SVL, head and limb of each individual were measured twelve times at set intervals over a total time period of 36 months. To estimate the growth curve of all traits for each individual, we fitted a cubic function using the repeated measurements of a particular morphological trait as dependent variable and age as independent variable. The parameters of this function differed significantly among traits and sexes, with the dewlap growing relatively faster than the other traits. Also, comparing the relative growth between males and females showed that dewlap size increases at a greater rate in males, with growth curves starting to diverge around the age of 8 months. Growth curves of head and limb dimensions, on the contrary, did not differ between the sexes.