Predictive Factors of Chemical and Visual Sensory Organ Size: The Roles of Sex, Environment, and Evolution

RUIZ-MONACHESI, M. R.; ABDALA, C. S.; SCHULTE, J. A.; CRUZ, F. B.

EVOLUTIONARY BIOLOGY

SPRINGER

Año: 2021

0071-3260

Animals obtain environmental information using different sensory modalities, and sensory organ size allows inferencesconcerning the importance of these modalities, which depend on numerous evolutionary or ecological factors. Here, wetest whether sex, different evolutionary processes and climatic factors explain chemical and visual sensory organ size inSouth American Liolaemus lizards as a model. We obtained snout volume (vomeronasal organ proxy), eye surface area, andcounted the number of secretory precloacal pores in males and females of 61 species. For evolutionary processes, we testedphylogenetic signal, and different evolutionary models; as well as compared evolutionary rate changes on these traits. We alsoexplored different climatic factors associated with changes in these traits. Our results showed the majority of studied traitshad low phylogenetic signal and fit a variety of models. Number of precloacal pores showed greater phylogenetic signal inboth sexes and best fit a model of evolution with differential rate transitions model, and have a more complex evolution infemales versus males. In males, snout volume correlated positively with precipitation, solar radiation and temperature; whilemale eye surface area was negatively associated with precipitation, solar radiation and wind speed. However, females appearto be more influenced by intrinsic evolutionary processes whereas males were more influenced by climatic factors. This isthe first study exploring the evolution of female precloacal pores in squamates reptiles in general and provides evidence thatsex and sensory modality type are strong predictive factors of sensory organ size.