My theory starts with an experience I had a few yrs ago while doing some scouting in early July. As I was sitting on a log taking a break, I saw movement towards the downwind side of me. It was a fawn, followed by another fawn, then Mama in tow. As the first fawn got to my scent stream, it immediately froze and started sniffing the wind. All 3 ran off. As I pondered my encounter, something dawned on me. I'm sure those fawns have never smelled a human that close, (70 yds) since it is extremely low human traffic in deer season, and non-existent in summer. They probably never smelled a human....but how did that fawn recognize me as danger ? My theory is that humans are predators , regardless of what the anti-hunters or non-hunters would want you to believe. That experience was more than enough proof of where I naturally belong in the food chain.
I would wager that the mama was key in knowing the danger and starting them running off. I've seen to many occasions were the fawns are in the clearing by a stand, have stopped and sniffed and looked at me the stand, only for Mama who had not been in the clearing to take off and the fawns go also.
I would agree with your observation, we are predators and scent will naturally alert prey, I don't believe it's a learned response.
I agree that it is an instinct ... more so natural, but I'm sure it is partly learned as they have more encounters by mother's behavior as well.
On the first encounter, I don't think the fawn smelled you and said "oh human, run". It was naturally startled from the scent smelling it for the first time. As someone said above, the fawn reacted, mama got a wiff and they ran off. Now the fawn associates the scent with danger. Deer are smart and learn quickly. At least that's my theory.
All meat eaters leave a 'meat eater' scent. When using urine from captive coyotes and foxes, many trappers are convinced that the animal has to be meat-fed instead of just kibble fed or the wild counterparts will sense something is wrong. Having said that, I think the fawn might have reacted the same way to smelling a vegan. Just like many critters that have never seen a snake will get all bent out of shape at the first sighting.
This was good for a laugh. A fawn will run away from a squirrel if startled. Where does that sit on the food chain?
The eyes have it. Stereoscopic/binocular vision is a trait shared by all predatory mammals. Only a very small percentage of primate species are strictly vegetarian.
Not just scent. Your eyes are set for binocular vision to judge distance n this set in the front. Same place as a lion, tiger, wolf, coyote, etc etc etc. Deer's eyes are set to the side to better see anything sneaking up like a cow, rabbit, etc etc etc sorry post above covered that
I've never seen a sasquatch, but if I saw one that was four times as tall as me, I'd probably look like a white Usain Bolt running out of those woods. I think it's that elemental for fawns.