A great big series theory about the alien and predator universe

This is a theory depicting how everything in the alien universe is what it is and how xenomorphs can have existed before human if an android created them. Simple answer, David created one type of alien and the predators created their own hundreds of years before. It also talks about a possible war between the Predators and engineers before the engineers were wiped out on LV426 by David using the black goo.