Sexual differences in locomotor performance in Tropidurus catalanensis lizards (Squamata: Tropiduridae) - body shape, size and limb musculature explain variation between males and females

Author(s)

Brandt, Renata ; De Barros, Fabio Cury ; Noronha, Carolina ; Jose Tulli, Maria ; Kohlsdorf, Tiana

• Document type: Journal article
• Source: Biological Journal of the Linnean Society; v. 118, n. 3, p. 598-609, JUL 2016.
• Web of Science Citations: 5

Abstract

Sexual dimorphism (SD) is the evolutionary outcome of selection acting differently on males and females. Several studies describe sexual differences in body size, although other morphological traits might be allometric between sexes and imply functional consequences. Here we test whether morphological differences between sexes in size and shape in the lizard Tropidurus catalanensis explain variation in performance of four locomotor traits. Our results show that males are larger than females and also exhibit longer limbs, longer muscles and larger muscle cross-sectional areas, while females have longer trunks and more sharped anterior claws; males outperform females in all locomotor performances measured. Sexual differences in sprinting and climbing is related with body size, and climbing performance is also explained by limb lengths, by differences in lengths and cross-sectional areas of specific muscles, and by interlimb distances. Between-sex differences in exertion are also related to SD, despite associations with sharper posterior claws that are independent of sex. Grasping performance, however, is associated with some muscle and morphological parameters that are not sexually dimorphic. Together our results suggest that morphology might be under sexual selection in T. catalanensis, given that better locomotor performance likely favours male lizards in typical activities of this polygenic species, such as territory defence and female acquisition. Moreover, the longer trunks that characterize females may confer more space to accommodate eggs. On the other hand, territory defence by males probably increases their exposure to predators, resulting in a synergistic effect of sexual and natural selection in the evolution of SD in T. catalanensis. (C) 2016 The Linnean Society of London (AU)

• FAPESP's process: 11/18868-1 - Evolution of meristic and morphometric diversity in the Autopodium of Squamata: patterns, processes and mechanisms
• Grantee: Tiana Kohlsdorf
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/24171-3 - Phenotypic adaptations in Tropidurus torquatus (Squamata, Tropiduridae): do peripheral populations evolve under local selective pressures?
• Grantee: Fábio Cury de Barros
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 11/01801-1 - Evolution of nocturnality in Gymnophthalmidae (Squamata): enzymatic thermal sensitivity
• Grantee: Carolina Ribeiro Noronha de Souza
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 12/51012-6 - Design and physiology compared between two of the most specious families of neotropical lizards: Liolaemidae versus Tropiduridae
• Grantee: Tiana Kohlsdorf
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/14125-0 - Integrative analysis of sexual dimorphism in lizards: morphology, functional significance and selection
• Grantee: Renata Brandt Nunes
• Support Opportunities: Scholarships in Brazil - Post-Doctoral