Evidence of constant diversification punctuated by a mass extinction in the African cycads
Article first published online: 11 DEC 2013
© 2013 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 4, Issue 1, pages 50–58, January 2014
How to Cite
Ecology and Evolution 2014; 4(1):50–58.
- Issue published online: 3 JAN 2014
- Article first published online: 11 DEC 2013
- Manuscript Accepted: 14 OCT 2013
- Manuscript Revised: 12 OCT 2013
- Manuscript Received: 16 JUN 2013
- Government of Canada through Genome Canada and the Ontario Genomics Institute. Grant Number: 2008-OGI-ICI-03
- University of Johannesburg
- Climate change;
- Encephalartos ;
- adaptive radiation;
- subtropical Africa.
The recent evidence that extant cycads are not living fossils triggered a renewed search for a better understanding of their evolutionary history. In this study, we investigated the evolutionary diversification history of the genus Encephalartos, a monophyletic cycad endemic to Africa. We found an antisigmoidal pattern with a plateau and punctual explosive radiation. This pattern is typical of a constant radiation with mass extinction. The rate shift that we found may therefore be a result of a rapid recolonization of niches that have been emptied owing to mass extinction. Because the explosive radiation occurred during the transition Pliocene–Pleistocene, we argued that the processes might have been climatically mediated.