The tribe Dr. Thapar studied is called the Asu and is found on the North American continent north of the Tarahumara of Mexico. Though it seems to be a highly developed society of its type, it has an overwhelming preoccupation with the care and feeding of the rac - an animal much like a bull in size, strength and temperament. In the Asu tribe, it is almost a social obligation to own at least one if not more racs. Anyone not possessing at least one is held in low esteem by the community because he is too poor to maintain one of the beasts properly. Some members of the tribe, to display their wealth and prestige, even own herds of racs.