ArticleProceedings of the National Academy of Sciences of the United States of America2012
Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 129 papers.
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Who cites it
129 citing papers in PubMed.
- Whole-Genome Sequencing Revealed Local Genetic Differences and Multi-Layered Genetic Structure in Asian Brown Bear (Ursus arctos) Populations.Genome biology and evolution · 2026Article
- Recent Dominant Transposition Events Affect Gene Regulatory Regions, but Not Coding Sequences, in Polar and Brown Bear Genomes.Current issues in molecular biology · 2026Article
- Genome sequencing uncovers the history of the Russian desman's gradual population decline and contributes to the evolutionary history of Talpidae.BMC ecology and evolution · 2026Article
- Coexisting With Humans: Genomic and Behavioral Consequences in a Small and Isolated Bear Population.Molecular biology and evolution · 2025Article
- Chromosome-scale Genomes Show Rapid Diversification and Ancient Gene Flow Among Bear Species.Genome biology and evolution · 2025Article
- Genomic and morphological analysis reveals long-term mammoth hybridization in British Columbia, Canada.Biology letters · 2025Article
- Article
- Habitat openness and squamate color evolution over deep time.Nature communications · 2025Article
- Bayesian Inference Under the Multispecies Coalescent with Ancient DNA Sequences.Systematic biology · 2024Article
- Five-leaf Generalizations of the D-statistic Reveal the Directionality of Admixture.Molecular biology and evolution · 2024Article
- The genomic natural history of the aurochs.Nature · 2024Article
- Color polymorphic carnivores have faster speciation rates.Scientific reports · 2024Article
- Late Pleistocene polar bear genomes reveal the timing of allele fixation in key genes associated with Arctic adaptation.BMC genomics · 2024Article
- Demographic History and Inbreeding in Two Declining Sea Duck Species Inferred From Whole-Genome Sequence Data.Evolutionary applications · 2024Article
- Mitogenomics reveals extremely low genetic diversity in the endangered Jilin clawed salamander: Implications for its conservation.Ecology and evolution · 2024Article
- Article
- The origins and diversification of Holarctic brown bear populations inferred from genomes of past and present populations.Proceedings. Biological sciences · 2024Article
- Inferring phylogenetic structure, taxa hybridization, and divergence times within rock voles of subgenusEcology and evolution · 2023Article
- Impact of Holocene environmental change on the evolutionary ecology of an Arctic top predator.Science advances · 2023Article
- Deep-time paleogenomics and the limits of DNA survival.Science (New York, N.Y.) · 2023Review
69 more citing papers are in PubMed but not listed here.
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26 authors.
Funding
Abstract
Polar bears (PBs) are superbly adapted to the extreme Arctic environment and have become emblematic of the threat to biodiversity from global climate change. Their divergence from the lower-latitude brown bear provides a textbook example of rapid evolution of distinct phenotypes. However, limited mitochondrial and nuclear DNA evidence conflicts in the timing of PB origin as well as placement of the species within versus sister to the brown bear lineage. We gathered extensive genomic sequence data from contemporary polar, brown, and American black bear samples, in addition to a 130,000- to 110,000-y old PB, to examine this problem from a genome-wide perspective. Nuclear DNA markers reflect a species tree consistent with expectation, showing polar and brown bears to be sister species. However, for the enigmatic brown bears native to Alaska's Alexander Archipelago, we estimate that not only their mitochondrial genome, but also 5-10% of their nuclear genome, is most closely related to PBs, indicating ancient admixture between the two species. Explicit admixture analyses are consistent with ancient splits among PBs, brown bears and black bears that were later followed by occasional admixture. We also provide paleodemographic estimates that suggest bear evolution has tracked key climate events, and that PB in particular experienced a prolonged and dramatic decline in its effective population size during the last ca. 500,000 years. We demonstrate that brown bears and PBs have had sufficiently independent evolutionary histories over the last 4-5 million years to leave imprints in the PB nuclear genome that likely are associated with ecological adaptation to the Arctic environment.
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