Throughout history, the size of the human head, and the brain has been limited by biology.  With the invention of the artificial womb, late in era-0, that limit was lifted.  Over many generations, this development led, with some assistance from genetic engineering, to the emergence of a subspecies of human, known as the Encephaloids.

Encephaloids mainly consisted of a large brain with just enough of a body to keep it alive.  Most spent their lives connected to large information systems, and frequently life-support assistance equipment to support their vestigial bodies.  Encephaloids usually took on careers that involved large amounts of information, as their large brains, and vestigial limbs made them uniquely unsuited for physical labor.

Many ships with an Encephaloid crew member had a special room, commonly known as “Mother’s Basement” that was built to house them in a supportive fluid matrix where they could spend all their time doing computational work attached to the ship’s computer system with all of their biological needs cared for by machines.

During the Great Reckoning, Encephaloids nearly went extinct as the Holy Empire of Man hunted them, because they were percieved as abberrations.