If memory servesThe orginal from Alien had more detail, but was harder to walk around in, so the simpler design in Aliens was made so it looked cooler in motion. Also you could cover it up by saying that the brood had taken on different genetic material and looked different as a result.
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Cadmus has teh uplikn coeds at,
Tue 24 Aug 2004, 0:15,
archived)