Board Thread:Warhammer 40k General Discussion/@comment-6589306-20130228113457/@comment-6078851-20150113174614

thanks sanguiniuslives, i'll be sure to check them out.

xeno's didn't come from tyranids, xeno's were a mix between bio-engineering and accident, see: 'prometheus'. but there's no reason why the alien franchise can't be within the 40k universe almost exactly where it is. the aliens franchise is set in our fairly close future (though we may have to push back the dates within it as we're approaching when it starts and we don't have some of the technologies required - cryostasis, interstellar travel ect), but 40k's universe has no records of anything before the year 20,000ish, only what emps remembers. to us right now 40k's citizens think of us as prehistoric, which is kinda accurate as we pre-date their recorded history :P

so while the events in the alien franchise transpire there are orks fighting eldar as the eldar rule supreme, and pay scant attention to the 'hairless monkeys' (that's us) who have barely worked out how to travel between star systems. slaanesh hasn't been born yet so warp travel is still relatively viable, and maybe the engineers had another experimental technology for space travel which gave them access to warp-space (the warp i reckon would be beyond even their comprehension). then it only takes one engineer ship with even a single egg on it (though we know how the engineers like to hoard and the ship would most likely be full of eggs :P) to be randomly ejected from warp-space in another galaxy billions of years earlier (remember that warp travel can result in backwards time travel also). the ship could be found by a spacefaring race, but even if the ship crashed on a planet alien eggs are insanely tough (they also have an unkown shelf-life and could theoretically survive for thousands of years in egg form), and in a ship full of eggs most of them would probably survive, then it just takes some ambulatory organism to be 'facehugged' and hey ho, a couple of billion years later we have the tyranid species :)