Research ArticleEVOLUTIONARY ECOLOGY

A new time tree reveals Earth history’s imprint on the evolution of modern birds

Science Advances  11 Dec 2015:
Vol. 1, no. 11, e1501005
DOI: 10.1126/sciadv.1501005

You are currently viewing the abstract.

View Full Text

Abstract

Determining the timing of diversification of modern birds has been difficult. We combined DNA sequences of clock-like genes for most avian families with 130 fossil birds to generate a new time tree for Neornithes and investigated their biogeographic and diversification dynamics. We found that the most recent common ancestor of modern birds inhabited South America around 95 million years ago, but it was not until the Cretaceous-Paleogene transition (66 million years ago) that Neornithes began to diversify rapidly around the world. Birds used two main dispersion routes: reaching the Old World through North America, and reaching Australia and Zealandia through Antarctica. Net diversification rates increased during periods of global cooling, suggesting that fragmentation of tropical biomes stimulated speciation. Thus, we found pervasive evidence that avian evolution has been influenced by plate tectonics and environmental change, two basic features of Earth’s dynamics.

Keywords
  • avian evolution
  • global biogeography
  • divergence times
  • diversification rates
  • K-Pg mass extinction

This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited.

View Full Text

More Like This