[QuarianRex]

Are humans xenophobic? Hell yeah! It has only been in the Last couple hundred years that we have even considered other races of man to be "human". We are the meanest, most aggressive, most bloodthirsty race on the planet. If we weren't we never would have made it this far.

Xenophobia (on a species wide level) is an instinctive evolutionary adaptation that promotes the survival of your own genepool. It ensures that you won't waste valuable resources on the preservation of someone (or something) elses genetics.

However, the other trait that seems to be distinctly human (besides being ornery bastards) is our capacity to over-ride instinct. This is especially true when the motivating force behind the instinct has been tamed, in the case it would be survival. For the most part we no longer need to worry about day-to-day survival and so we afford ourselves the luxury of equality.

When I say equality I don't just mean among humans. Animal rights activists, greenpeace, and vegitarians are all products of our self-assured survival.

This would apply to extra-terrestrial contact as well. So long as said contact was peaceful (ie. did not threaten our survival) our species wide benevolence would continue. If, however, our survival were to be called into question we would have no difficulty in reverting to the efficient engines of destruction that two billion years of evolution has shaped us to be.