Board Thread:Warhammer 40k General Discussion/@comment-7186329-20130329201743/@comment-8881468-20130502150120

to quote the tyranid article  ". If the Hive Fleet is victorious, the fleet will descend to the planet, inhaling the atmosphere, drinking the seas, and basically consuming all organic biomass until nothing more than a lifeless ball of rock remains."

you need raw materials and atmosphere to have orkoid life