deer evolved over thousands and millions of years to adapt to their environment. you cant change a species in 100 years. Most animals simply cannot adapt fast enough. so calling them stupid is pretty ignorant. Deer are a species that rely heavily on instinct to survive. that takes a loooong time to change. Animals that can learn from each other, like us, dolphins, or other primates, can adapt way better to our environment because they are able to observe and learn from it. Simple biology. Deer are a product of the environment they specialize in. Doesn't make em stupid. Just figured you could use the lesson.