POSITIVE CORRELATION BETWEEN DIVERSIFICATION RATES AND PHENOTYPIC EVOLVABILITY CAN MIMIC PUNCTUATED EQUILIBRIUM ON MOLECULAR PHYLOGENIES
Article first published online: 16 APR 2012
© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
Volume 66, Issue 8, pages 2622–2627, August 2012
How to Cite
Rabosky, D. L. (2012), POSITIVE CORRELATION BETWEEN DIVERSIFICATION RATES AND PHENOTYPIC EVOLVABILITY CAN MIMIC PUNCTUATED EQUILIBRIUM ON MOLECULAR PHYLOGENIES. Evolution, 66: 2622–2627. doi: 10.1111/j.1558-5646.2012.01631.x
- Issue published online: 26 JUL 2012
- Article first published online: 16 APR 2012
- Accepted manuscript online: 21 MAR 2012 09:25PM EST
- Received September 11, 2011 , Accepted February 13, 2012
- Adaptive radiation;
- morphological evolution;
The hypothesis of punctuated equilibrium proposes that most phenotypic evolution occurs in rapid bursts associated with speciation events. Several methods have been developed that can infer punctuated equilibrium from molecular phylogenies in the absence of paleontological data. These methods essentially test whether the variance in phenotypes among extant species is better explained by evolutionary time since common ancestry or by the number of estimated speciation events separating taxa. However, apparent “punctuational” trait change can be recovered on molecular phylogenies if the rate of phenotypic evolution is correlated with the rate of speciation. Strong support for punctuational models can arise even if the underlying mode of trait evolution is strictly gradual, so long as rates of speciation and trait evolution covary across the branches of phylogenetic trees, and provided that lineages vary in their rate of speciation. Species selection for accelerated rates of ecological or phenotypic divergence can potentially lead to the perception that most trait divergence occurs in association with speciation events.