They're known as pizzlies or grolars, and they're a fusion of the Arctic white bear and their brown cousins. It's a blend that's been turning up more and more in parts of Alaska and Western Canada.
Bears sharing both species' DNA have been recorded several times over the past decade. So why are these two species linking up?
It's called flexible mate choice: The bears are mating with the best possible partners as opposed to not mating at all, and they're mating because they share relatively close territories and the same branches of the same evolutionary tree.
Intraspecies mixing between the two happened thousands of years ago, thanks to the advance and retreat of glaciers, and of late, it has been boosted by climate change.
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