Sunnygal
By highest, what exactly do you mean? Just because other species don't think the way we do does not make us higher or intellectually superior to them. This, I think, is where the problem lies. We as human animals feel that we are superior because we have reached out to communicate with other species on our own planet and because they don't communicate back to us in the same way, we negate their intelligence.
I don't do that. I think animals have what we have -emotions, intelligence, etc, only to a lesser extent. Heck, i watch a spider react to danger, or packing up its bags and marching off to find a new place, and i marvel. Then there's my cat, my little girl buddy ...