The first known member was Leonard Detweiler, a proponent of human genetic engineering who left Beowulf and became the founder of the Mesa colony and the slaving corporation known in later centuries as Manpower Incorporated. The Detweilers faked extinction of the Detweiler line, going into hiding to manage Mesa without most Mesans even knowing about their existence. As with certain other Mesan families, the males of the Detweiler family were essentially clones of Leonard Detweiler. (HH11, SI2)