It is difficult to say which creature is superior to another, within evolutionary theory you can only say (in hindsight) which creature is more apt to its environment. Both creatures and environments change under each others influence, especially when talking about humans. So I think that talking about superiority or even "superiority" in this respect is a category mistake. The most you can claim is that, given a certain constant environment, the species that survives longer, or thrives and grows is superior to that which decays and dwindles, but this is not an absolute, context-free kind of superiority, but only limited to that specifc environment. It is meningless to claim that cockroaches are superior to humans because they could survive a worldwide nuclear fallout, but nevertheless they are more apt to survive in those conditions. Superiority, IMHO, is not proper of the species, but of the individual and can only be judged by the standards one sets for himslef, by the ideals he chooses for his life, by the quality of his actions and words. Superiority, has nothing to do then with survival, hence is unrelated to evolutionism and species as such. A noble death can determine the (moral) superiority of an individual, or the culture that spawned him/her, but says nothing about the species. As you may note, the distinction male/female play no role at all in this. Biologically speaking male and female in a bisexual species must cultivate a sort of symbiosis for the species to survive, hence they are both equally necessary for the continuation of the species and of the same value.
Funny that nobody yet addressed the monogamy/polygamy issue ...