THE CHALLENGE OF SPECIES DELIMITATION AT THE EXTREMES: DIVERSIFICATION WITHOUT MORPHOLOGICAL CHANGE IN PHILIPPINE SUN SKINKS
Article first published online: 26 AUG 2013
© 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.
Volume 67, Issue 12, pages 3556–3572, December 2013
How to Cite
Barley, A. J., White, J., Diesmos, A. C. and Brown, R. M. (2013), THE CHALLENGE OF SPECIES DELIMITATION AT THE EXTREMES: DIVERSIFICATION WITHOUT MORPHOLOGICAL CHANGE IN PHILIPPINE SUN SKINKS. Evolution, 67: 3556–3572. doi: 10.1111/evo.12219
- Issue published online: 2 DEC 2013
- Article first published online: 26 AUG 2013
- Accepted manuscript online: 29 JUL 2013 06:44AM EST
- Manuscript Accepted: 8 JUL 2013
- Manuscript Received: 18 MAR 2013
- University of Kansas (KU) Panorama fund and the KU Office of Graduate Studies Doctoral Student research fund to AJB
- National Science Foundation DEB 0743491 to RMB
- cryptic species;
An accurate understanding of species diversity is essential to studies across a wide range of biological subdisciplines. However, delimiting species remains challenging in evolutionary radiations where morphological diversification is rapid and accompanied by little genetic differentiation or when genetic lineage divergence is not accompanied by morphological change. We investigate the utility of a variety of recently developed approaches to examine genetic and morphological diversity, and delimit species in a morphologically conserved group of Southeast Asian lizards. We find that species diversity is vastly underestimated in this unique evolutionary radiation, and find an extreme case where extensive genetic divergence among lineages has been accompanied by little to no differentiation in external morphology. Although we note that different conclusions can be drawn when species are delimited using molecular phylogenetics, coalescent-based methods, or morphological data, it is clear that the use of a pluralistic approach leads to a more comprehensive appraisal of biodiversity, and greater appreciation for processes of diversification in this biologically important geographic region. Similarly, our approach demonstrates how recently developed methodologies can be used to obtain robust estimates of species limits in “nonadaptive” or “cryptic” evolutionary radiations.