Erinaceids are generally
shrew-like in form, with long snouts and short tails. They are, however, much larger than shrews, ranging from in body length and in weight, in the case of the
short-tailed gymnure, up to and in the
moonrat. All but one species have five toes in each foot, in some cases with strong claws for digging, and they have large eyes and ears. Hedgehogs possess hair modified into sharp
spines to form a protective covering over the upper body and flanks, while gymnures have only normal hair. Most species have anal
scent glands, but these are far better developed in gymnures, which can have a powerful odor. Erinaceids are
omnivorous, with the major part of their diet consisting of insects, earthworms, and other small
invertebrates. They also eat seeds and fruit, and occasionally birds' eggs, along with any
carrion they come across. Their teeth are sharp and suited for impaling invertebrate prey. The
dental formula for erinaceids is: Hedgehogs are
nocturnal, but gymnures are less so, and may be active during the day. Many species live in simple burrows, while others construct temporary nests on the surface from leaves and grass, or shelter in hollow logs or similar hiding places. Erinaceids are solitary animals outside the breeding season, and the father plays no role in raising the young. Female erinaceids give birth after a gestation period of around six to seven weeks. The young are born blind and hairless, although hedgehogs begin to sprout their spines within 36 hours of birth. ==Evolution==