Stick insect genomes reveal natural selection's role in parallel speciation.
Natural selection can drive the repeated evolution of reproductive isolation, but the genomic basis of parallel speciation remains poorly understood. We analyzed whole-genome divergence between replicate pairs of stick insect populations that are adapted to different host plants and undergoing parallel speciation. We found thousands of modest-sized genomic regions of accentuated divergence between populations, most of which are unique to individual population pairs. We also detected parallel genomic divergence across population pairs involving an excess of coding genes with specific molecular functions. Regions of parallel genomic divergence in nature exhibited exceptional allele frequency changes between hosts in a field transplant experiment. The results advance understanding of biological diversification by providing convergent observational and experimental evidence for selection's role in driving repeatable genomic divergence.
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
Víctor
V
Soria-Carrasco
Department of Biology, Utah State University, Logan, UT 84322, USA.
Zachariah
Z
Gompert
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
Aaron A
AA
Comeault
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
Timothy E
TE
Farkas
Deparment of Biology, University of Nevada, Reno, NV 89557, USA.
Thomas L
TL
Parchman
Department of Entomology, Texas A&M University, College Station, TX 77843, USA.
J Spencer
JS
Johnston
Department of Botany, University of Wyoming, Laramie, WY 82071, USA.
C Alex
CA
Buerkle
Department of Biology, Notre Dame University, South Bend, IN 46556, USA.
Jeffrey L
JL
Feder
J. F. Blumenbach Institute of Zoology and Anthropology, University of Göttingen, 37073 Göttingen, Germany.
Jens
J
Bast
Department of Ecology and Evolution, University of Lausanne, Lausanne CH-1015, Switzerland.
Tanja
T
Schwander
Department of Ecology and Evolutionary Biology, Rice University, Houston, TX 77005, USA.
Scott P
SP
Egan
Department of Biological Sciences, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
Bernard J
BJ
Crespi
Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK. p.nosil@sheffield.ac.uk.
Patrik
P
Nosil
D000818:Animals; D031952:Ceanothus; D005787:Gene Frequency; D049810:Genetic Speciation; D014644:Genetic Variation; D049750:Genome, Insect; D060434:Herbivory; D007313:Insecta / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D012641:Selection, Genetic