WHEN does the grizzly bear cross the road? Answer: Very rarely – and that’s bad news for bears in the northern US and southern Canada.
A team of Canadian biologists used DNA fingerprinting to track the migration of 470 grizzlies near Canada’s Highway 3, a major east-to-west route through the Rocky Mountains and two adjoining ranges. The team obtained DNA from individual bears via hair samples snagged in barbed-wire strands set around smelly bait. Since bears from different populations carry a different mix of genetic types at 15 highly variable regions in the genome, the researchers were able to separate out…
