Okay. I went back to thread 1 to review. You posted: First: "I don't think it's so much camoflauge as it is heightening the odor." I don't agree with this. Heightening the odor for what? Second: "An added thought on the behavior is pack behavior. A pack of dogs rolls in the same shit. In the same rotting carcasses. A pack of dogs has a communal pack smell." This is a very good point. I definitely agree that it is pack behavior, but I do not think that it is "communal pack smell" behavior in the sense that it is somehow decided on by the pack. It is to camouflage their own scent when on the hunt. Third: I stated that: "They do it to conceal their own scent....They also piss on locations, out of instinct, so as to mark their territory ” And you replied: "And you don't see the contradiction there?" I do see why you might think there is a contradiction here, but I do not think that there is one. One the one hand, they conceal their scent for the aggressive predatory hunt. On the other hand, they mark their scent through their urine to be recognized by similar species so as to let them know that this is their territory. As pack animals, if another wolf (or a bear or mountain lion) were to decide to invade another wolf's territory (same species), he knows that he can expect a struggle or a fight with the alpha. I don't think that the prey would recognize this as such, although this is a good area to research. The history of the evolution of mammalian behavior tells us that predatory mammals roll in shit and carcasses to hide (camouflage) their scent. If you come across any scientific sources to the contrary, I would be most interested in reading them. Also, thanks a lot for telling me about the July, 2006 Scientific American article, "What Bird's See." I find it fascinating that primates reevolved a third cone from a mutation after losing two of the original four, but I do not fully understand the author's diagram on page 74 of the UV bird spectrum locus as being 3-dimensional compared to ours as being 2-dimensional. Perhaps when I reread that part at a later date, something will click. Thanks a lot though!