is typically associated with the beginning of "mammalian" oxygen consumption rates and the origins of endothermy. If gorgonopsians were inertial homeotherms, it is not impossible that they had hair. The snout is typically riddled with foramina (small holes which confer with blood vessels), which could potentially point to the existence of loose skin (as opposed to scales), hair, various skin glands (such as sweat glands), and whiskers; however, some reptiles present a similar patterning of foramina, which are instead related to dental development rather than skin. Palaeopathology The anterolateral aspect of the left radius (a forearm bone) of the gorgonopsian specimen NHCC LB396 presents a circular bony lesion, featuring irregular-to-radial spikes made of cortical bone surrounded by a thin layer of subperiosteal bone, which grew rapidly over a single growing season. This is consistent with periostitis most likely stemming from subperiosteal haematoma. This specific condition as well as the fast growth rate are more reminiscent of mammals and dinosaurs than crocodilians or monitor lizards. Among early synapsids, the only other pathology noted is osteomyelitis in several pelycosaur groups. The labial (tongue) side of the tooth root of a functional canine of RB382 presents as many as 8 lesions, clustering along the midline of the tooth, which resemble miniature teeth with a pulp, dentine, and a thin enamel coating. They are roughly circular—with diameters varying from –though they become less circular at around the middle point of the root until passing the cervix of the tooth. This is roughly consistent with the human ailment odontoma, the most frequent type of odontogenic tumour, which previously only extended a few million years back in the fossil record. At 255 million years old, RB382 presents the oldest known case of odontoma. The adult snout SAM-PK-11490 from an indeterminate Middle Permian gorgonopsian species has an imbedded tooth from an unidentifiable animal. The bone developed a callus around the tooth, indicating it healed and the individual survived the attack. It either came from a predator — namely a biarmosuchian, a therocephalian, or another gorgonopsian — or intraspecific face biting as is commonly exhibited in social predators — such as big cats or monitor lizards, and it has been suggested for several extinct lineages such as theropods, aquatic reptiles, and saber-toothed cats. Social biting is intended to assert dominance or facilitate breeding, and, if correct, suggests at least some Middle Permian gorgonopsians were social carnivores. The tooth