Rapid morphological evolution in placental mammals post-dates the origin of the crown group.

ABSTRACT: Resolving the timing and pattern of early placental mammal evolution has been confounded by conflict among divergence date estimates from interpretation of the fossil record and from molecular-clock dating studies. Despite both fossil occurrences and molecular sequences favouring a Cretaceous origin for Placentalia, no unambiguous Cretaceous placental mammal has been discovered. Investigating the differing patterns of evolution in morphological and molecular data reveals a possible explanation for this conflict. Here, we quantified the relationship between morphological and molecular rates of evolution. We show that, independent of divergence dates, morphological rates of evolution were slow relative to molecular evolution during the initial divergence of Placentalia, but substantially inc

SUBMITTER: Halliday TJD 

PROVIDER: S-EPMC6458320 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature