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Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change

Overview of attention for article published in Proceedings of the National Academy of Sciences of the United States of America, July 2012
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  • In the top 5% of all research outputs scored by Altmetric
  • High Attention Score compared to outputs of the same age (99th percentile)
  • High Attention Score compared to outputs of the same age and source (99th percentile)

Citations

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250 Dimensions

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651 Mendeley
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4 CiteULike
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Title
Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change
Published in
Proceedings of the National Academy of Sciences of the United States of America, July 2012
DOI 10.1073/pnas.1210506109
Pubmed ID
Authors

W. Miller, S. C. Schuster, A. J. Welch, A. Ratan, O. C. Bedoya-Reina, F. Zhao, H. L. Kim, R. C. Burhans, D. I. Drautz, N. E. Wittekindt, L. P. Tomsho, E. Ibarra-Laclette, L. Herrera-Estrella, E. Peacock, S. Farley, G. K. Sage, K. Rode, M. Obbard, R. Montiel, L. Bachmann, O. Ingolfsson, J. Aars, T. Mailund, O. Wiig, S. L. Talbot, C. Lindqvist

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.

Twitter Demographics

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Mendeley readers

The data shown below were compiled from readership statistics for 651 Mendeley readers of this research output. Click here to see the associated Mendeley record.

Geographical breakdown

Country Count As %
United States 19 3%
Canada 5 <1%
Germany 3 <1%
Russia 3 <1%
United Kingdom 3 <1%
France 3 <1%
Sweden 3 <1%
South Africa 1 <1%
Austria 1 <1%
Other 14 2%
Unknown 596 92%

Demographic breakdown

Readers by professional status Count As %
Student > Ph. D. Student 166 25%
Researcher 140 22%
Student > Master 81 12%
Student > Bachelor 74 11%
Professor > Associate Professor 35 5%
Other 99 15%
Unknown 56 9%
Readers by discipline Count As %
Agricultural and Biological Sciences 388 60%
Biochemistry, Genetics and Molecular Biology 72 11%
Environmental Science 57 9%
Earth and Planetary Sciences 14 2%
Arts and Humanities 10 2%
Other 43 7%
Unknown 67 10%

Attention Score in Context

This research output has an Altmetric Attention Score of 330. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 25 July 2021.
All research outputs
#65,406
of 20,109,407 outputs
Outputs from Proceedings of the National Academy of Sciences of the United States of America
#1,608
of 93,778 outputs
Outputs of similar age
#276
of 140,374 outputs
Outputs of similar age from Proceedings of the National Academy of Sciences of the United States of America
#10
of 916 outputs
Altmetric has tracked 20,109,407 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 99th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 93,778 research outputs from this source. They typically receive a lot more attention than average, with a mean Attention Score of 33.8. This one has done particularly well, scoring higher than 98% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 140,374 tracked outputs that were published within six weeks on either side of this one in any source. This one has done particularly well, scoring higher than 99% of its contemporaries.
We're also able to compare this research output to 916 others from the same source and published within six weeks on either side of this one. This one has done particularly well, scoring higher than 99% of its contemporaries.