The roles of phylogeny and climate in shaping variation in life-history traits of the newt genus Triturus (Caudata, Salamandridae)

Abstract

Assessing the origin of trait variation during evolutionary history is an important first step in understanding evolutionary diversification. Here, we tested the influence of shared ancestry and climate, and the interplay of both, on the variation of ten life history traits in Triturus newts. We showed that (1) climate alone has driven the evolution of variation in live life history traits, (2) phylogenetic signal partly explains the variation in two traits (vitellus diameter and snout-vent length of larvae at metamorphosis), and (3) the interplay of shared ancestry and climate explains the variation in one trait (snout-vent length of larvae at metamorphosis). This study highlights the coarse-grained influence of shared ancestry and climate on the structure of phenotypic trait variation in Triturus and provides a handle for more detailed, fine grained studies on the evolution of phenotypic trait variation.