and is important to its physiology, social behaviour and locomotion. It acts as a counterbalance to aid stability when the devil is moving quickly. An ano-genital scent gland at the base of its tail is used to mark the ground behind the animal with its strong, pungent scent. The male has external testes in a pouch-like structure formed by lateral ventrocrural folds of the abdomen, which partially hides and protects them. The testes are subovoid in shape and the mean dimensions of 30 testes of adult males was . The female's pouch opens backwards, and is present throughout its life, unlike some other dasyurids. The Tasmanian devil has the most powerful bite relative to body size of any living mammalian carnivore, exerting a force of . The jaw can open to 75–80 degrees, allowing the devil to generate the large amount of power to tear meat and crush bones—sufficient force to allow it to bite through thick metal wire. The power of the jaws is in part due to its comparatively large head. The teeth and jaws of Tasmanian devils resemble those of hyenas, an example of convergent evolution. Dasyurid teeth resemble those of primitive marsupials. Like all dasyurids, the devil has prominent canines and cheek teeth. It has three pairs of lower incisors and four pairs of upper incisors. These are located at the top of the front of the devil's mouth. Like dogs, it has 42 teeth, however, unlike dogs, its teeth are not replaced after birth but grow continuously throughout life at a slow rate. It has a "highly carnivorous dentition and trophic adaptations for bone consumption". The devil has long claws that allow it to dig burrows and seek subterranean food easily and grip prey or mates strongly. The teeth and claw strength allow the devil to attack wombats up to in weight. The large neck and forebody that give the devil its strength also cause this strength to be biased towards the front half of the body; the lopsided, awkward, shuffling gait of the devil is attributed to this. The devil has long whiskers on its face and in clumps on the top of the head. These help the devil locate prey when foraging in the dark, and aid in detecting when other devils are close during feeding. The whiskers can extend from the tip of the chin to the rear of the jaw and