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Authors

Zofia A. Kaliszewska, Harvard University
Jon Seger, University of Utah
Victoria J. Rowntree, Ocean Alliance/Whale Conservation Institute, Lincoln, Massachusetts & Instituto de Conservación de Ballenas, Miñones 1986, Buenos Aires , Argentina
Amy R. Knowlton, Ocean Alliance/Whale Conservation Institute, Lincoln, Massachusetts & Instituto de Conservación de Ballenas, Miñones 1986, Buenos Aires, Argentina
Kim Marshalltilas, Ocean Alliance/Whale Conservation Institute, Lincoln, Massachusetts, & Instituto de Conservación de Ballenas, Buenos Aires, Argentina
Nathalie J. Patenaude, Marine Mammal Research Group, Graduate School of Environment, Macquarie University, Sydney, NSW 2109, Australia
Mariana Rivarola, ALUAR, Ruta Provincial N ° 4, U9120OIA Puerto Madryn, Chubut, Argentina
Catherine M. Schaeff, American University
Mariano Sironi, Instituto de Conservación de Ballenas, Miñones 1986, Buenos Aires C1428ATD, Argentina
Wendy A. Smith, University of Utah
Tadasu K. Yamada, National Science Museum, 3-23-1 Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan
Susan G. Barco, Virginia Marine Science Museum, 717 General Booth Boulevard, Virgina Beach, Virginia
Rafael Benegas, Hydro Sport, Av. de las Ballenas S/N, Puerto Pirámides, Chubut, Argentina
Peter B. Best, Mammal Research Institute, University of Pretoria, Pretoria 0002, South Africa
Moira W. Brown, New England Aquarium, Central Wharf
Robert L. Brownell Jr., Southwest Fisheries Science Center, National Marine Fisheries ServiceFollow
Robert Harcourt, Marine Mammal Research Group, Graduate School of Environment, Macquarie University, Sydney, NSW 2109, Australia
Alejandro Carribero, Ecocentro, Julio Verne 3784, U9129OJA, Puerto Madryn, Chubut, Argentina

Date of this Version

2005

Comments

Published in Molecular Ecology (2005) 14, 3439–3456.

Abstract

Right whales carry large populations of three ‘whale lice’ (Cyamus ovalis, Cyamus gracilis, Cyamus erraticus) that have no other hosts. We used sequence variation in the mitochondrial COI gene to ask (i) whether cyamid population structures might reveal associations among right whale individuals and subpopulations, (ii) whether the divergences of the three nominally conspecific cyamid species on North Atlantic, North Pacific, and southern right whales (Eubalaena glacialis, Eubalaena japonica, Eubalaena australis) might indicate their times of separation, and (iii) whether the shapes of cyamid gene trees might contain information about changes in the population sizes of right whales. We found high levels of nucleotide diversity but almost no population structure within oceans, indicating large effective population sizes and high rates of transfer between whales and subpopulations. North Atlantic and Southern Ocean populations of all three species are reciprocally monophyletic, and North Pacific C. erraticus is well separated from North Atlantic and southern C. erraticus. Mitochondrial clock calibrations suggest that these divergences occurred around 6 million years ago (Ma), and that the Eubalaena mitochondrial clock is very slow. North Pacific C. ovalis forms a clade inside the southern C. ovalis gene tree, implying that at least one right whale has crossed the equator in the Pacific Ocean within the last 1–2 million years (Myr). Low-frequency polymorphisms are more common than expected under neutrality for populations of constant size, but there is no obvious signal of rapid, interspecifically congruent expansion of the kind that would be expected if North Atlantic or southern right whales had experienced a prolonged population bottleneck within the last 0.5 Myr.

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