Twaddle. As Darwin would be the first to tell you, evolutionary fitness is a matter of fucking, not fighting.
I'm not supporting creationists' arguements now but you're missing an important point that at least among more complex animals it's the largest, strongest, meanest and to add to it usually the more experienced ones who are able to, as you say, fuck. Of course an actual confrontation does not always take place (and it doesn't always mean death fight - some species avoid fights that result in severe wounds and potentially death). Sometimes a demonstration of force is enaugh. And of course there are other means to conquer or attract a mate, especially among birds. But the general rule stays.