Picture this: Hunter-trapper Brian LaDoon was taking care of his pack of Husky dogs on a Canadian tundra and German photographer Norbert Rosing was setting up his cameras, when out of nowhere a large polar bear walked up to one of the dogs.
Brian knew that the bear had not eaten for months, and thought it was "curtains" for the dog when something completely unexpected happened: the polar bear and the dog started playing with each other!
Here's a fantastic audio slideshow (lots of neat pics) given by Stuart Brown about the encounter: http://speakingoffaith.publicradio.org/programs/play/audiogallery/soundseen.shtml - Thanks Jennie!
So, it doesn't appear to be an isolated event. There are also reports of young grizzly bears and wolves playing with each other, and even hunting together. Though the grizzly usually runs off the wolves when it comes down to which gets the kill.
Inane joke aside, the "lonely" comments made by other people on this deal are, in my perception, probably fairly accurate. The social ranking system of dogs, and what not. The Husky might be low in rank, or a reject. The polar bear may have sensed it's non-aggressiveness and smelled no threatening pharemones or whatever and figured the dog would be a friendly playmate. The dog, perceiving no threat from the polar bear for the same reasons, did not feel under threat. Sort of like two latent gays in a public restroom. Sometimes it just happens. And the body language and what not. See?