and weigh from about . Some miniature horses are no taller than in adulthood. Sexual dimorphism is limited in equines. The penis of the male is vascular and lacks a bone (baculum). Equines are adapted for running and traveling over long distances. Their dentition is adapted for grazing; they have large incisors that clip grass blades and highly crowned, ridged molars well suited for grinding. Males have spade-shaped canines ("tushes"), which can be used as weapons in fighting. Equines have fairly good senses, particularly their eyesight. Their moderately long, erect ears are movable and can locate the source of a sound. A dun-colored coat with primitive markings that include a dorsal stripe and often leg striping and transverse shoulder stripes reflect the wildtype coat and are observed in most wild extant equine species. Only the mountain zebra lacks a dorsal stripe. In domestic horses, dun color and primitive markings exist in some animals across many breeds. The purpose of the bold black-and-white striping of zebras has been a subject of debate among biologists for over a century, but 2014 evidence supports the theory that they are a form of protection from biting flies. These insects appear to be less attracted to striped coats, and compared to other wild equines, zebras live in areas with the highest fly activity. With the exception of the domestic horses, which have long manes that lay over the neck and long tail hair growing from the top of the tailhead or dock, most equines have erect manes and long tails ending in a tuft of hair. The coats of some equine species undergo shedding in certain parts of their range and are thick in the winter. Ecology and daily activities Extant wild equines have scattered ranges across Africa and Asia. The plains zebra lives in lush grasslands and savannas of Eastern and Southern Africa, while the mountain zebra inhabits mountainous areas of southwest Africa. The other equine species tend to occupy more arid environments with more scattered vegetation. Grévy's zebra is found in thorny scrubland of East Africa, while the African wild ass inhabits rocky deserts of North Africa. The two Asian wild ass species live in the dry deserts of the Near East and Central Asia and Przwelski's wild horse's habitat is the deserts of Mongolia. Only the range of the plains and Grévy's zebras overlap. In addition to wild populations, domesticated horses and