And polar bears aren't the only ones who harbor curiously close cousins. One group of brown bears on Alaska's Alexander Archipelago, in fact, has a genetic makeup more closely related to modern polar bears than their fellow brown bears elsewhere around the globe.
Conservation through climate change
Lindqvist and her team see the nuclear genome as their next step in tracking down polar bears' past—and possibly their future. More clues from that code, Lindqvist says, can "provide us with a genetic window into past environments and into how polar bears evolved in response to climate change."
A nuclear genome would give the researchers more crucial information about the polar bear's physical characteristics, elucidating how the owner of the ancient jawbone was evolving to rule over its harsh landscape. For example, Lindqvist says, "If we're able to retrieve more of the nuclear genome, we'll be able to get hold of at least some genes that are known to be in charge of coat colors in other mammals."
And lessons from these ancient and minuscule parcels of information can make a difference in preservation practices in the future. "There are a lot of really powerful ways we can use genetics for conservation and management," Waits says. She is investigating the interplay between genetics and the landscape itself to better understand how changes in habitat—whether climatic or manmade—impact a species's genetic make up over time in hopes of improving wildlife corridors and management under the conditions of climate change and continued human development.
The polar bear's short history has already revealed itself to be one of nimble evolutionary moves. And the new findings present "another example of how rapidly—in evolutionary terms—species can evolve," Lindqvist notes, a lesson we know well from human evolution, as well. "This is just yet another very astonishing example that such a specialized species can evolve fairly rapidly to probably fill an opening of habitat—a new niche—in response to climate change." And it promises to play an important role, the authors pointed out, in understanding "how polar bears will be able to cope with the predicted changes of their main habitat."