I've got to agree with GMMAT on this one, I don't beleive that deer have a brain that is capable of reasoning that a car is dangerous. I think that the reason that they are soalert in the woods would be like you and mewalking down the street and passing a "thug" and not thinking twice about it but if we get home and the same "thug" is in our house it become flight or fight. It's a survival instinct.