Current address: National Institute for Mathematical and Biological Synthesis, University of Tennessee, 1534 White Avenue Suite 400, Knoxville, Tennessee 37996.
HYBRIDIZATION, SPECIES COLLAPSE, AND SPECIES REEMERGENCE AFTER DISTURBANCE TO PREMATING MECHANISMS OF REPRODUCTIVE ISOLATION
Article first published online: 29 APR 2011
© 2011 The Author(s).
Volume 65, Issue 9, pages 2592–2605, September 2011
How to Cite
Gilman, R. T. and Behm, J. E. (2011), HYBRIDIZATION, SPECIES COLLAPSE, AND SPECIES REEMERGENCE AFTER DISTURBANCE TO PREMATING MECHANISMS OF REPRODUCTIVE ISOLATION. Evolution, 65: 2592–2605. doi: 10.1111/j.1558-5646.2011.01320.x
- Issue published online: 1 SEP 2011
- Article first published online: 29 APR 2011
- Accepted manuscript online: 11 APR 2011 05:27AM EST
- Received October 6, 2010, Accepted March 26, 2011
- reproductive isolation;
There are now a number of well-studied cases in which hybridization between closely related sympatric species has increased, sometimes resulting in the replacement of species pairs by hybrid swarms. Many of these cases have been linked to anthropogenic environmental change, but the mechanisms leading from environmental change to species collapse, and the long-term effects of hybridization on species pairs, remain poorly understood. We used an individual-based stochastic simulation model to explore the conditions under which disturbances that weaken premating barriers to reproduction patterns between sympatric species might lead to increased hybridization and to species collapse. Disturbances often resulted in bouts of hybridization, but in many cases strong reproductive isolation spontaneously reemerged. This was sometimes true even after hybrid swarms had replaced parental species. The reemergence of species pairs was most likely when disturbances were of short duration. Counterintuitively, incipient species pairs were more likely to reemerge after strong but temporary disturbances than after weaker disturbances of the same duration. Even temporary bouts of hybridization often led to substantial homogenization of species pairs. This suggests that ecosystem managers may be able to refill ecological niches, but in general will not be able to resurrect lost species after species collapse.