Scientists sequence entire genomes of 4 bear species, making it possible to analyze the evolutionary history of all bears at the genome level. It shows that gene flow, or gene exchange, between species by extensive hybridization, is possible between most bear species - not only polar and brown bear.

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Scientists sequence entire genomes of 4 bear species, making it possible to analyze the evolutionary history of all bears at the genome level. It shows that gene flow, or gene exchange, between species by extensive hybridization, is possible between most bear species - not only polar and brown bear.