 Aetosaurs were herbivores , likely feeding on ferns and seed ferns that were common in the Triassic . The upturned shape of their snout suggests that aetosaurs may have dug up roots and tubers . Aetosaurs have several anatomical features that may have been adaptations to digging , including a short radius relative to the humerus ( seen in many other digging tetrapods ) and a large deltopectoral crest on the humerus that served as an attachment for muscles . Aetosaurs also have large hind feet , or pes , with large claws that were likely used for skratch @-@ digging . One aetosaur , Typothorax , has an entepicondyle on the humerus , which is the origin of forearm pronator and manual flexor muscles often used in digging . Moreover , it has a large olecranon process on the ulna which projects backward past the elbow , giving a large area for the insertion of the triceps muscle . While many studies have suggested that aetosaurs had a fossorial or burrowing lifestyle , aetosaurs have few of the characteristics that fossorial animals have as adaptations to digging . Therefore , it is likely that aetosaurs were able to dig to some extent , possibly rooting for food , but were unable to burrow . 
