Show Details

Polar Bear Genetics

January 14, 2015

Melting sea ice is has resulted in a recent northward shift in polar bear genes.




For the past three generations, polar bear genes have been shifting northward. (U.S. Fish & Wildlife Service/Public Domain)

Arctic bear genetics. I’m Bob Hirshon and this is Science Update.

Polar bears depend on Arctic sea-ice to hunt their prey. But climate change is melting the ice and making habitat scarce. By analyzing the flow of their genes, scientists have now confirmed that the bears have been recently moving toward areas where more sea-ice persists. USGS biologist Lily Peacock led the study.


In the last 1 to 3 generations we see this unidirectional increase in gene flow from southern Canada towards the Canadian Archipelago, and this suggests that the genes are essentially moving northward.


In contrast, an analysis of ancient populations uncovered completely random gene flow, pointing to human induced climate change as the cause of the current genetic shift. Understanding the genetics of polar bear movement could help conservation efforts as their habitat contracts. The study appears in the journal PLoS ONE. I’m Bob Hirshon, for AAAS, the science society.