Cold comfort: The incredible moment a wild polar bear pets a sled dog in Canada

This is the adorable - and extraordinary - moment a wild polar bear pets a chained-up sled dog in the Canadian wilds

Polar bears weigh 330-990lbs and can easily kill a dog, especially one on a chain. But this footage, shot by David De Meulles of Manitoba, shows the bear gently stroking the placid animal on the head.
'I had no idea what was going to happen, and then sure enough he started petting that dog, acted like he was a friend,' De Meulles told CBC. 
I just so happened to catch a video of a lifetime.'