Data from: Partial genomic survival of cave bears in living brown bears

Although many large mammal species went extinct at the end of the
Pleistocene epoch, their DNA may persist due to past episodes of
interspecies admixture. However, direct empirical evidence of the
persistence of ancient alleles remains scarce. Here, we present multifold
coverage genomic data from four Late Pleistocene cave bears (Ursus
spelaeus complex) and show that cave bears hybridized with brown bears
(Ursus arctos) during the Pleistocene. We develop an approach to assess
both the directionality and relative timing of gene flow. We find that
segments of cave bear DNA still persist in the genomes of living brown
bears, with cave bears contributing 0.9 to 2.4% of the genomes of all
brown bears investigated. Our results show that even though extinction is
typically considered as absolute, following admixture, fragments of the
gene pool of extinct species can survive for tens of thousands of years in
the genomes of extant recipient species.