What an ancient jawbone reveals about polar bear evolution

Popular Science quoted Charlotte Lindqvist about her research looking at the intertwined evolutionary histories of polar bears and brown bears. Becoming separate species did not completely stop these animals from mating with each other. Scientists have known this for some time, but the new research draws on an expanded dataset — including DNA from an ancient polar bear jawbone — to tease out more detail. “When [polar bears] die, their remains end up on the seafloor,” said Lindqvist. “The formation and maintenance of species can be a messy process,” she said. “What’s happened with polar bears and brown bears is a neat analog to what we’re learning about human evolution: that the splitting of species can be incomplete.”