anybody, or anything, can have keen senses but it takes brains to remember that smelling rubber boots means a hunter and smelling acorns means food. and yes deer do follow the same trails every day, and yes maybe it is scent. but how do deer follow the same scrape or rub lines a year later, surely after all the snow a rain from a whole year the scent would be gone. and anyway this isn't about HOW smart the deer are, its about HOW LONG their memmory lasts. the same thing was said about goldfish having a 3 second memmory and the mythbusters on discovery channel tested it and found there memmory to be very good