During my trip to the Arctic last month, I had the opportunity to spend time with Brendan Kelly, one of the world's leading Arctic biologists. Brendan and I spoke at some length about his work on ringed seals. (It'll be part of a feature on Arctic food webs in the Spring 2011 issue of On Earth magazine.) We also touched on the topic of hybrid animals, and how global warming may be increasing their number in the Arctic. In today's issue of Nature, Brendan and two colleagues report the first two confirmed observations of grizzly-polar bear hybrids, as well as other hybrids being seen up north. My own piece on his study was published by On Earth's web site today. Brendan's list of 34 potential Arctic hybrids makes for particularly interesting reading. Photographer Steven Kazlowski, who provided the shot of the (possible) grolar bear, lives and works just up the road from me in Kingston, Washington, and his book The Last Polar Bear is one of the great environmental books of the last decade (published by the good folks at Seattle's Braided River books). Very interesting stuff happening up in the great white north.