tailieunhanh - Body size divergence promotes post-zygotic reproductive isolation in centrarchids

Today, approximately one in every hundred babies born in the US is conceived using ART. Growth in the use and scientific refinement of ART is carefully monitored by the American Society for Reproductive Medicine (ASRM) and its affiliate, the Society for Assisted Reproductive Technology (SART), whose memberships consist of specialists in this field of medicine. In December 2009, ASRM convened a meeting of professionals, patient advocates, congressional and federal agency representatives, legal experts, and consumers to examine the oversight of ART. This document reflects the information provided at the conference | Evolutionary Ecology Research 2006 8 903-913 Body size divergence promotes post-zygotic reproductive isolation in centrarchids Daniel I. Bolnick 1 Thomas J. Near2 and Peter C. Wainwright3 1 Section of Integrative Biology University of Texas at Austin One University Station C0930 Austin TX 78712-0253 -Department of Ecology and Evolutionary Biology Yale University New Haven CT 06520 and 3Section of Evolution and Ecology University of California at Davis Storer Hall Davis CA 95616 USA ABSTRACT Question Does morphological divergence accelerate the evolution of post-zygotic reproductive isolation Data incorporated Estimates of divergence time between species body size divergence and hybrid embryo viability in the freshwater fish family Centrarchidae. Method of analysis We estimated the age of each node in the phylogeny using penalized likelihood calibrated with multiple fossil dates. We then regressed the average body size and hybrid viability at each phylogenetic node against the node s age. Residuals from these regressions were compared to test for time-independent relationships between body size divergence and post-zygotic reproductive isolation. Conclusions Morphologically divergent species tend to experience stronger post-zygotic reproductive isolation than expected given their age. These results suggest that morphological divergence between species is associated with an accelerated accumulation of genetic incompatibilities and highlight one potential avenue by which ecological divergence may facilitate speciation. Keywords genetic incompatibility hybridization reproductive isolation speciation. INTRODUCTION In recent years there has been extensive interest in the role of morphological divergence in speciation Schluter 2000 Coyne and Orr 2004 Rundle and Nosil 2005 . Morphological divergence can facilitate reproductive isolation if the differences between populations reduce the likelihood of mating or the survival of hybrids. Pre-mating isolation can occur if .