The Rats

A tiny tribe of beings in Ireland, who were cannibalistic and inbred with gusto, were encountered in the ancient past by the Atreides people moving into the area of Britain. Rather than eliminate the entirety of these people, who were very ugly, and whose culture was an abomination, the Atreides chose to eliminate the adults, and raise the children away from the perverse culture.

A direct descendant of this tribe was Thomas Aldous Rawling.

This tribe, after time travel became prevalent, was later discovered to have descended, not from primates, along with the rest of Terran humanity, but from giant rats, that essentially lived around a lake, largely eating lake trout, after they had at least partially, emerged from the cave system that had spawned them.