Your definition of "superior" is biased. Intelligence is not necessarily an advantage. If deer devoted a higher percentage of their bodymass to their brains (and became smarter), then a lower percentage of their bodymass would be devoted to muscle and digestion.
That may not seem like a big deal, but a smart deer that can't outrun a wolf is dinner. Moreover, a smart deer that doesn't have a gut complex enough to digest cellulose isn't going to survive. If you look, you'll see that extant species have evolved to reach "superior positions" -- biologists call that finding a niche. But that niche can take any number of forms.
Man cannot outrun a wolf, but used his brain to devise methods to counteract the danger of the wolf or other creatures. A deer of comparable mental ability could do so as well. As little as 50k years ago, a mere eyeblink of geologic time, there were giant deer, sloths, sabertoothed this and that, even sabertoothed kangaroos, but they are all gone. Did their niches change? Or did man upset the evolutionary processes by his mere existence?..............