Female-biased gape and body-size dimorphism in the New World watersnakes (tribe: Thamnophiini) oppose predictions from Rensch's rule.

ABSTRACT:

Abstract

Sexual-size dimorphism (SSD) is ubiquitous across animals and often biased in the direction of larger females in snakes and other ectothermic organisms. To understand how SSD evolves across species, Rensch's rule predicts that in taxa where males are larger, SSD increases with body size. In contrast, where females are larger, SSD decreases with body size. While this rule holds for many taxa, it may be ambiguous for others, particularly ectothermic vertebrates. Importantly, this rule suggests that the outcomes of SSD over phylogenetic time scales depend on the direction of dimorphism predicated on the difference in reproductive efforts between males and females. Here, we examine SSD in the context of Rensch's rule in Thamnophiini, the gartersnakes and watersnakes, a promine

SUBMITTER: Burbrink FT 

PROVIDER: S-EPMC6745821 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature