F. Hailer
Evolutionary history of brown and polar bears
Hailer, F.; Welch, A.J.
Abstract
Taxonomists have long recognised polar and brown bears as separate species with distinct ecological niches and largely nonoverlapping ranges. Surprisingly, phylogenetic studies of maternally inherited mitochondrial DNA (mtDNA) found polar bears nested within brown bears, with an estimated divergence time of <170 000 years. This indicated an unusually rapid speciation and adaptation of polar bears. However, several recent studies of autosomal and Y‐chromosomal DNA have revisited these findings, giving independent perspectives of bear evolutionary history. Results show that polar bears cluster separately from brown bears, and divergence time estimates are older than those based on mtDNA, ranging from >300 000 to 4–5 million years. These studies confirm uniqueness of the polar bear lineage, provide more time for speciation and adaptation, and have uncovered numerous candidate genes for evolutionary adaptations. Several instances of introgressive hybridisation between polar and brown bears have been inferred, revealing trans‐species transmission of mtDNA and some nuclear loci.
Citation
Hailer, F., & Welch, A. (2016). Evolutionary history of brown and polar bears. In Encyclopedia of life sciences (1-8). John Wiley and Sons. https://doi.org/10.1002/9780470015902.a0026303
Publication Date | Jul 15, 2016 |
---|---|
Deposit Date | Apr 6, 2016 |
Publicly Available Date | Apr 13, 2016 |
Pages | 1-8 |
Book Title | Encyclopedia of life sciences. |
ISBN | 9780470015902 |
DOI | https://doi.org/10.1002/9780470015902.a0026303 |
Public URL | https://durham-repository.worktribe.com/output/1667023 |
Contract Date | Mar 31, 2016 |
Files
Accepted Book Chapter
(3.4 Mb)
PDF
Copyright Statement
This is the accepted version of the following article: Hailer, F. & Welch, A.J. (15 July 2016). Evolutionary history of brown and polar bears. eLS. John Wiley & Sons Ltd, Chichester, which has been published in final form at https://doi.org/10.1002/9780470015902.a0026303. This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
You might also like
Not all farms are created equal: Shady African cocoa farms promote a richer bat fauna
(2023)
Journal Article
Downloadable Citations
About Durham Research Online (DRO)
Administrator e-mail: dro.admin@durham.ac.uk
This application uses the following open-source libraries:
SheetJS Community Edition
Apache License Version 2.0 (http://www.apache.org/licenses/)
PDF.js
Apache License Version 2.0 (http://www.apache.org/licenses/)
Font Awesome
SIL OFL 1.1 (http://scripts.sil.org/OFL)
MIT License (http://opensource.org/licenses/mit-license.html)
CC BY 3.0 ( http://creativecommons.org/licenses/by/3.0/)
Powered by Worktribe © 2024
Advanced Search