Ancient hybridization and an irish origin for the modern polar bear matriline

Ceiridwen J. Edwards, Marc A. Suchard, Philippe Lemey, John J. Welch, Ian Barnes, Tara L. Fulton, Ross Barnett, Tamsin C. O'Connell, Peter Coxon, Nigel Monaghan, Cristina E. Valdiosera, Eline D. Lorenzen, Eske Willerslev, Gennady F. Baryshnikov, Andrew Rambaut, Mark G. Thomas, Daniel G. Bradley, Beth Shapiro

Research output: Contribution to journalArticle

122 Citations (Scopus)

Abstract

Background: Polar bears (Ursus maritimus) are among those species most susceptible to the rapidly changing arctic climate, and their survival is of global concern. Despite this, little is known about polar bear species history. Future conservation strategies would significantly benefit from an understanding of basic evolutionary information, such as the timing and conditions of their initial divergence from brown bears (U. arctos) or their response to previous environmental change. Results: We used a spatially explicit phylogeographic model to estimate the dynamics of 242 brown bear and polar bear matrilines sampled throughout the last 120,000 years and across their present and past geographic ranges. Our results show that the present distribution of these matrilines was shaped by a combination of regional stability and rapid, long-distance dispersal from ice-age refugia. In addition, hybridization between polar bears and brown bears may have occurred multiple times throughout the Late Pleistocene. Conclusions: The reconstructed matrilineal history of brown and polar bears has two striking features. First, it is punctuated by dramatic and discrete climate-driven dispersal events. Second, opportunistic mating between these two species as their ranges overlapped has left a strong genetic imprint. In particular, a likely genetic exchange with extinct Irish brown bears forms the origin of the modern polar bear matriline. This suggests that interspecific hybridization not only may be more common than previously considered but may be a mechanism by which species deal with marginal habitats during periods of environmental deterioration.

LanguageEnglish
Pages1251-1258
Number of pages8
JournalCurrent Biology
Volume21
Issue number15
Early online date7 Jul 2011
DOIs
Publication statusPublished - 9 Aug 2011
Externally publishedYes

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Ursidae
Ursus maritimus
Ice
Deterioration
Conservation
Ursus arctos
hybridization
Climate
climate
environmental degradation
interspecific hybridization
refuge habitats
Ecosystem
Arctic region
ice
History
history
habitats

Cite this

Edwards, C. J., Suchard, M. A., Lemey, P., Welch, J. J., Barnes, I., Fulton, T. L., ... Shapiro, B. (2011). Ancient hybridization and an irish origin for the modern polar bear matriline. Current Biology, 21(15), 1251-1258. https://doi.org/10.1016/j.cub.2011.05.058
Edwards, Ceiridwen J. ; Suchard, Marc A. ; Lemey, Philippe ; Welch, John J. ; Barnes, Ian ; Fulton, Tara L. ; Barnett, Ross ; O'Connell, Tamsin C. ; Coxon, Peter ; Monaghan, Nigel ; Valdiosera, Cristina E. ; Lorenzen, Eline D. ; Willerslev, Eske ; Baryshnikov, Gennady F. ; Rambaut, Andrew ; Thomas, Mark G. ; Bradley, Daniel G. ; Shapiro, Beth. / Ancient hybridization and an irish origin for the modern polar bear matriline. In: Current Biology. 2011 ; Vol. 21, No. 15. pp. 1251-1258.
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Edwards, CJ, Suchard, MA, Lemey, P, Welch, JJ, Barnes, I, Fulton, TL, Barnett, R, O'Connell, TC, Coxon, P, Monaghan, N, Valdiosera, CE, Lorenzen, ED, Willerslev, E, Baryshnikov, GF, Rambaut, A, Thomas, MG, Bradley, DG & Shapiro, B 2011, 'Ancient hybridization and an irish origin for the modern polar bear matriline', Current Biology, vol. 21, no. 15, pp. 1251-1258. https://doi.org/10.1016/j.cub.2011.05.058

Ancient hybridization and an irish origin for the modern polar bear matriline. / Edwards, Ceiridwen J.; Suchard, Marc A.; Lemey, Philippe; Welch, John J.; Barnes, Ian; Fulton, Tara L.; Barnett, Ross; O'Connell, Tamsin C.; Coxon, Peter; Monaghan, Nigel; Valdiosera, Cristina E.; Lorenzen, Eline D.; Willerslev, Eske; Baryshnikov, Gennady F.; Rambaut, Andrew; Thomas, Mark G.; Bradley, Daniel G.; Shapiro, Beth.

In: Current Biology, Vol. 21, No. 15, 09.08.2011, p. 1251-1258.

Research output: Contribution to journalArticle

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AU - Suchard, Marc A.

AU - Lemey, Philippe

AU - Welch, John J.

AU - Barnes, Ian

AU - Fulton, Tara L.

AU - Barnett, Ross

AU - O'Connell, Tamsin C.

AU - Coxon, Peter

AU - Monaghan, Nigel

AU - Valdiosera, Cristina E.

AU - Lorenzen, Eline D.

AU - Willerslev, Eske

AU - Baryshnikov, Gennady F.

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AU - Thomas, Mark G.

AU - Bradley, Daniel G.

AU - Shapiro, Beth

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