Taxonomic status of Antarctic killer whales

July 24, 2015

Principal Investigator: Phillip Morin, Marine Mammal Genetics Program

Three Antarctic killer whale ecotypes; Illustration by Uko GorterKiller whales have long been known to be comprised of sympatric 'ecotypes', with discrete prey preferences, morphology and behaviors. Although these ecotypes avoid social interactions and are not known to interbreed, genetic studies to date have found extremely low levels of diversity in the mitochondrial control region, and few clear phylogeographic patterns worldwide. New high-throughput DNA sequencing techniques allowed us to sequence the entire mitochondrial genomes from 450 killer whales sampled globally, and provided strong evidence that most of the killer whale types are evolutionarily distinct from the others, with between 150,000 and 350,000 years of independent evolution.

Ongoing studies illustrate the power of genomics to understand evolutionary patterns and processes, including the factors involved in rapid diversification and adaptation of killer whales on a global scale.

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More Antarctic killer whale research in the Marine Mammal and Turtle Division

Morin, P.A., Parsons, K.M., Archer, F.I., Ávila-Arcos, M.C., Barrett-Lennard, L.G., Dalla Rosa, L., Duchêne, S., Durban, J.W., Ellis, G., Ferguson, S.H., Ford, J.K., Ford, M., Garilao, C., Gilbert, M.T.P., Kaschner, K., Matkin, C.O., Petersen, S.D., Robertson, K.M., Visser, I.N., Wade, P.R., Ho, S.Y.W., Foote, A.D., 2015. Geographic and temporal dynamics of a global radiation and diversification in the killer whale. Molecular Ecology in press.

Foote, A.D., Morin, P.A., 2015. Sympatric speciation in killer whales? Heredity 114: 537-538.

Foote, A. D, P.A. Morin, R. L. Pitman, M. C. Ãvila-Arcos, J. W. Durban, A. Van Helden, M.-H. S. Sinding and M. T. P. Gilbert.  2013.  Mitogenomic insights into a recently described and rarely observed killer whale morphotype.  Polar Biology: 36: 1519-1523.

Foote, A.D., P.A. Morin, J.W. Durban, E. Willersley, L. Orlando, and M.T.P Gilbert.  2011.  Out of the Pacific and back again: insights into the matrilineal history of Pacific killer whale ecotypes.  PLoS ONE 6: e24980.

Foote, A. D., P. A. Morin, J. W. Durban, R. L. Pitman, P. Wade, E. Willerslev, M. T. P. Gilbert and R. R. Da Fonseca. 2010. Positive selection on the killer whale mitogenome. Biology Letters 7: 116-118

LeDuc, R. G., K. M. Robertson, and R. L. Pitman. 2008. Mitochondrial sequence divergence among Antarctic killer whale ecotypes is consistent with multiple species. Biology Letters 4:426-429.

Morin, P. A., F. I. Archer, A. D. Foote, J. Vilstrup, E. E. Allen, P. Wade, J. Durban, K. Parsons, R. Pitman, L. Li, P. Bouffard, S. A. Nielsen, M. Rasmussen, E. Willerslev, M. T. P. Gilbert and T. Harkins. 2010. Complete mitochondrial genome phylogeographic analysis of killer whales (Orcinus orca) indicates multiple species. Genome Research 20: 908-916.

Pitman, R. L. and P. Ensor. 2003. Three forms of killer whales (Orcinus orca) in Antarctic waters. Journal of Cetacean Research and Management 5: 131-139.

Pitman, R. L., W. L. Perryman, D. Leroi and E. Eilers. 2007. A dwarf form of killer whale in the Antarctic. Journal of Mammalogy 88: 43-48.

Last modified: 10/4/2016