13 mai 2016
Why are some species older than others ? A large-scale study of vertebrates [BMC Evolutionary Biology]
Keywords : species age, intraspecific diversification, latitude, viviparity, oviparity, colour polymorphism
Strong variations are observed between and within taxonomic groups in the age of extant species and these differences can clarify factors that render species more vulnerable to extinction. Understanding the factors that influence the resilience of species is thus a key component of evolutionary biology, but it is also of prime importance in a context of climate change and for conservation in general. We explored the effect of extrinsic and intrinsic factors on the timing of the oldest diversification event in over 600 vertebrate species distributed worldwide. We used phylogenetic comparative methods to show that color polymorphism, latitude and reproduction (the latter through its interaction with latitude) affected the timing of the oldest diversification event within a species.