If you pay attention, you will notice that the aliens of the Hive look very similar to the Fallen: long fingers, actually four arms, which are cut off of some Fallen, same body structure ... So I ask you, what do you think? Are the members of the Hive ejected or perhaps undead Fallen? (Above is a picture of the Hive members and here is one of a Fallen: http://img2.wikia.nocookie.net/__cb20130510122813/destinypedia/images/a/a9/Captain.png )