TY - JOUR

T1 - Selection on ancestral genetic variation fuels repeated ecotype formation in bottlenose dolphins

AU - Marie, Louis

AU - Marco, Galimberti

AU - Frederick, Archer

AU - Simon, Berrow

AU - Andrew, Brownlow

AU - Ramon, Fallon

AU - Milaja, Nykänen

AU - Joanne, O’Brien

AU - M., Roberston Kelly

AU - E., Rosel Patricia

AU - Benoit, Simon-Bouhet

AU - Daniel, Wegmann

AU - C., Fontaine Michael

AU - D., Foote Andrew

AU - E., Gaggiotti Oscar

N1 - doi: 10.1126/sciadv.abg1245

PY - 2021/10/27

Y1 - 2021/10/27

N2 - Studying repeated adaptation can provide insights into the mechanisms allowing species to adapt to novel environments. Here, we investigate repeated evolution driven by habitat specialization in the common bottlenose dolphin. Parapatric pelagic and coastal ecotypes of common bottlenose dolphins have repeatedly formed across the oceans. Analyzing whole genomes of 57 individuals, we find that ecotype evolution involved a complex reticulated evolutionary history. We find parallel linked selection acted upon ancient alleles in geographically distant coastal populations, which were present as standing genetic variation in the pelagic populations. Candidate loci evolving under parallel linked selection were found in ancient tracts, suggesting recurrent bouts of selection through time. Therefore, despite the constraints of small effective population size and long generation time on the efficacy of selection, repeated adaptation in long-lived social species can be driven by a combination of ecological opportunities and selection acting on ancestral standing genetic variation.

AB - Studying repeated adaptation can provide insights into the mechanisms allowing species to adapt to novel environments. Here, we investigate repeated evolution driven by habitat specialization in the common bottlenose dolphin. Parapatric pelagic and coastal ecotypes of common bottlenose dolphins have repeatedly formed across the oceans. Analyzing whole genomes of 57 individuals, we find that ecotype evolution involved a complex reticulated evolutionary history. We find parallel linked selection acted upon ancient alleles in geographically distant coastal populations, which were present as standing genetic variation in the pelagic populations. Candidate loci evolving under parallel linked selection were found in ancient tracts, suggesting recurrent bouts of selection through time. Therefore, despite the constraints of small effective population size and long generation time on the efficacy of selection, repeated adaptation in long-lived social species can be driven by a combination of ecological opportunities and selection acting on ancestral standing genetic variation.

U2 - 10.1126/sciadv.abg1245

DO - 10.1126/sciadv.abg1245

M3 - Article

VL - 7

JO - Science Advances

JF - Science Advances

SN - 2375-2548

IS - 44

M1 - eabg1245

ER -