Examination Room (TFTD)
We now have the evidence to work out why Aliens capture humans. They are not food, they are not fertilised with Alien embryos, rather they form the basis of a range of creatures and control systems. Alien technology is based on a common mind, a shared intellect and the human brain is the ideal receptacle for these systems. Human brain tissue is used in most of the Alien biological computer storage and retrieval systems, the remains are used for building and for breeding.
These tiles are never encountered in the game, but if added to your stores through hacking, can be researched. They sell for $9000 per unit.