TY - JOUR
T1 - Genome-wide congealing and rapid transitions across the speciation continuum during speciation with gene flow
AU - Feder, Jeffrey L.
AU - Nosil, Patrik
AU - Wacholder, Aaron C.
AU - Egan, Scott P.
AU - Berlocher, Stewart H.
AU - Flaxman, Samuel M.
N1 - Funding Information:
We thank Kerry Shaw, participants in the 2013 American Genetic Association Annual Symposium, Sergey Gavrilets, and an anonymous reviewer for valuable feedback. This work utilized the Janus supercomputer, which is supported by the National Science Foundation (award number CNS-0821794) and the University of Colorado Boulder. The Janus supercomputer is a joint effort of the University of Colorado Boulder, the University of Colorado Denver and the National Center for Atmospheric Research.
Funding Information:
The National Science Foundation; the US Department of Agriculture; the Notre Dame Environmental Change Initiative and program in Advanced Diagnostics and Therapeutics (to J.L.F.); the European Research Council (NatHisGen. 129639 to P.N.); the National Science Foundation through the University of Colorado Biofrontiers Institute Interdisciplinary Quantitative Biology Program (IGERT 1144807) to A.C.W.
Publisher Copyright:
© 2014 © The American Genetic Association. 2014. All rights reserved.
PY - 2014
Y1 - 2014
N2 - Our current understanding of speciation is often based on considering a relatively small number of genes, sometimes in isolation of one another. Here, we describe a possible emergent genome process involving the aggregate effect of many genes contributing to the evolution of reproductive isolation across the speciation continuum. When a threshold number of divergently selected mutations of modest to low fitness effects accumulate between populations diverging with gene flow, nonlinear transitions can occur in which levels of adaptive differentiation, linkage disequilibrium, and reproductive isolation dramatically increase. In effect, the genomes of the populations start to "congeal" into distinct entities representing different species. At this stage, reproductive isolation changes from being a characteristic of specific, divergently selected genes to a property of the genome. We examine conditions conducive to such genome-wide congealing (GWC), describe how to empirically test for GWC, and highlight a putative empirical example involving Rhagoletis fruit flies. We conclude with cautious optimism that the models and concepts discussed here, once extended to large numbers of neutral markers, may provide a framework for integrating information from genome scans, selection experiments, quantitative trait loci mapping, association studies, and natural history to develop a deeper understanding of the genomics of speciation.
AB - Our current understanding of speciation is often based on considering a relatively small number of genes, sometimes in isolation of one another. Here, we describe a possible emergent genome process involving the aggregate effect of many genes contributing to the evolution of reproductive isolation across the speciation continuum. When a threshold number of divergently selected mutations of modest to low fitness effects accumulate between populations diverging with gene flow, nonlinear transitions can occur in which levels of adaptive differentiation, linkage disequilibrium, and reproductive isolation dramatically increase. In effect, the genomes of the populations start to "congeal" into distinct entities representing different species. At this stage, reproductive isolation changes from being a characteristic of specific, divergently selected genes to a property of the genome. We examine conditions conducive to such genome-wide congealing (GWC), describe how to empirically test for GWC, and highlight a putative empirical example involving Rhagoletis fruit flies. We conclude with cautious optimism that the models and concepts discussed here, once extended to large numbers of neutral markers, may provide a framework for integrating information from genome scans, selection experiments, quantitative trait loci mapping, association studies, and natural history to develop a deeper understanding of the genomics of speciation.
KW - divergent selection
KW - genetic hitchhiking
KW - genomic architecture
KW - linkage disequilibrium
KW - speciation with gene flow
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U2 - 10.1093/jhered/esu038
DO - 10.1093/jhered/esu038
M3 - Article
C2 - 25149256
AN - SCOPUS:84913601872
SN - 0022-1503
VL - 105
SP - 810
EP - 820
JO - Journal of Heredity
JF - Journal of Heredity
IS - S1
ER -