Elevated from comments, if you are interested in the fate of polar bears this book review is definitely for you
Guest Post by Dr. Susan Crockford [with emphases added by hro]
Dr. Susan J. Crockford is a zoologist with more than 35 years experience, including work on the Holocene history of Arctic animals. Like Ian Stirling, Susan Crockford earned her undergraduate degree in zoology at the University of British Columbia. Polar bear evolution is one of Dr. Crockford’s professional interests, which she discusses in her book, Rhythms of Life: Thyroid Hormone and the Origin of Species (see www.rhythmsoflife.ca and www.pacificid.com).