Mebber,
                                    Undefined,
                                    15 years ago                                
                                
                                    You do not understand the Xenos true nature. They're born killers, they can 	accommodate to ANY circumstances. And they are much more intelligent than you think. Not in a way "we" would say intelligent, but in a very strange, animalistic way. Their intellect is not focused on writing poetry, calculate a mathematic formula or construct great buildings. Their intellect is focused on survival. And  in that way, they're genii.
Do you think it is a coincident Xenos always know how to find the weakpoint in a defense grid? WY has made A LOT of projects concerning about xenomorph research and capture. All end in disaster. 
IMHO there are four reasons the bugs always failed: 
1) luck - the humans always had a BUNCH of luck
2) total contamination - that means the complete destruction of the contaminated areas by using weapons of mass destruction.
3) remarkable competent individuals - like Ripley and Harrison. 
4) last but not least, all of the movie directors where humans.