Similarities between Xenomorphs and SJ's??

the question is whether the similarities were intended by Ridley Scott and Dan O'bannon, or is it because H.R. Giger designed both, so both got the bio-mechanical look.

It is an interesting point to bring up. I was fortunate to recieve [i]Alien Vault[/i] as a present this Christmas (it is an amazing book and I'd advise anyone to get a copy if they are able to.) Anywho...there is a piece in the book that states the Space Jockey itself and the Alien have similar features; in particular the fact that both creatures sport a very skeletal rib cage. The book briefly quotes Ridley (I can't cite off hand) but essentially it suggests that the source of the eggs in the silo came from whatever burst out the Space Jockey. [img]http://www.gadgetmadness.com/archives/original_1979_alien.jpg[/img] [img]http://images.wikia.com/aliens/images/2/26/SpaceJockey.jpg[/img]

Yeah they both seem biomechanical in origin in my opinion! Could this be because in fact, BOT species were created by another unknown species we'll see in Prometheus??