Killer whale nuclear genome and mtDNA reveal widespread population bottleneck during the last glacial maximum.
Ecosystem function and resilience is determined by the interactions and independent contributions of individual species. Apex predators play a disproportionately determinant role through their influence and dependence on the dynamics of prey species. Their demographic fluctuations are thus likely to reflect changes in their respective ecological communities and habitat. Here, we investigate the historical population dynamics of the killer whale based on draft nuclear genome data for the Northern Hemisphere and mtDNA data worldwide. We infer a relatively stable population size throughout most of the Pleistocene, followed by an order of magnitude decline and bottleneck during the Weichselian glacial period. Global mtDNA data indicate that while most populations declined, at least one population retained diversity in a stable, productive ecosystem off southern Africa. We conclude that environmental changes during the last glacial period promoted the decline of a top ocean predator, that these events contributed to the pattern of diversity among extant populations, and that the relatively high diversity of a population currently in productive, stable habitat off South Africa suggests a role for ocean productivity in the widespread decline.
School of Biological and Biomedical Sciences, Durham University, Durham, United Kingdom.
Andre E
AE
Moura
Charlene
C
Janse van Rensburg
Malgorzata
M
Pilot
Arman
A
Tehrani
Peter B
PB
Best
Meredith
M
Thornton
Stephanie
S
Plön
P J Nico
PJ
de Bruyn
Kim C
KC
Worley
Richard A
RA
Gibbs
Marilyn E
ME
Dahlheim
Alan Rus
AR
Hoelzel
D000818:Animals; D002467:Cell Nucleus / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D017753:Ecosystem; D019143:Evolution, Molecular; D014644:Genetic Variation; D005828:Genetics, Population; D016678:Genome; D006239:Haplotypes; D008390:Markov Chains; D008957:Models, Genetic; D011157:Population Dynamics; D013997:Time Factors; D050685:Whale, Killer / Q000235:genetics*
D004272:DNA, Mitochondrial
Cetacea; demographics; genomics; population bottleneck