I want to say it was in the Galapagos islands, but not certain. Either or it was a wild dog that had been brought over with sailors, onto an island, and was left for whatever reason. This dog(s) was isolated and needed to feed, so it began to hunt. Its prey was in trees and so over generation they began to climb and hunt in the trees. I remember seeing this on some Discovery program, the dog had light colored hair and very much resembled the primates with long noses and sharp teeth. I was wondering if anyone recognizes this description and knows what animal that is. Or maybe i am a bit more imaginative than i thought.