The body shape of the cynodont illustrated here is based on Thrinaxodon, a small creature no larger than a cat. Teeth from a larger cynodont however, have been found in the Petrified Forest in Arizona, suggesting a creature at least 1.5 metres long. Small holes in the fossil snout suggest whiskers, which, in turn, suggest hair. The presence of fur, needed for temperature control, strongly indicates that cynodonts were warm-blooded.
