All species › Hedgehogs, shrews and moles
Hedgehogs, shrews and moles | Eulipotyphla
Insecteneters | Eulipotiflos
Small, short-legged mammals with a long, pointed, mobile snout that does the work the eyes do in other orders: sight is weak, and the animal steers by smell and touch, with dense bundles of whiskers on the muzzle. The cheekteeth carry high sharp cusps that meet in a W- or V-shaped pattern and cut through the chitin armour of insects and the body of an earthworm; in most groups the front incisors are enlarged into a pair of forceps. The rate of living is high, and many species must eat every few hours. Winter is therefore not passed the same way throughout: hedgehogs hibernate in earnest on autumn fat, moles dig deeper, and shrews stay active the year round. Litters are large and the young are born naked and blind.
Families in this order
- Hedgehogs | Erinaceidae7 speciesThe spines are modified hairs: each is stiffened inside by lengthwise ridges and sits in the skin on a thin flexible neck, so that a blow is absorbed rather than passed on. Beneath the spiny skin, a ring of muscle runs round the whole outline of the body and is drawn tight like a purse string; head, legs and the soft haired belly disappear under the closed spiny mantle. The snout is long and mobile, and the animal relies on smell and hearing. The cheekteeth carry broad blunt cusps that crush beetles, worms and snails. Faced with a strong smell they work up a frothy saliva and spread it over the spines with the tongue. The northern species hibernate in earnest on autumn fat; the desert species do not, but have very large ears and long legs that hold the body clear of the hot sand.
- Shrews | Soricidae25 speciesVery small mammals with a long pointed snout full of whiskers, minute eyes and a rate of living so high that most species must eat every few hours or die. The tooth cusps are sharp and cutting; in the red-toothed shrews they are stained red-brown by iron built into the enamel of the tips, which slows their wear. Glands on the flanks give off a musky smell that makes the animals inedible to many predators — a cat will kill one but not eat it. The water shrews swim with fringes of stiff hairs along feet and tail and disable prey with venomous saliva. Several species shrink in autumn: weight, organs and even the brain decrease, and grow partly back in spring. Litters follow one another quickly, and in some species the young trail behind the mother in a caravan, each gripping the fur of the one in front.
- Moles and desmans | Talpidae9 speciesOne family, two ways of living unseen. Moles are cylindrical, with a short coat that stands upright in the skin and will lie either way, so that the animal can also back up its tunnel without rubbing the hairs against the grain. The forelimb is turned outwards and joined to the body just behind the head, the hand is broad as a spade, and a sickle-shaped extra bone at the wrist widens the palm further still. The eyes are minute and often skinned over, external ears are absent, and hunting goes by touch: the snout is set with dense fields of extremely sensitive touch organs, and a permanent tunnel system is patrolled because earthworms fall into it. Those worms are disabled with a bite to the head and stored alive in chambers. The desmans share the family's traits but live in cold running water, with a long, flattened, highly mobile snout, webbed hind feet and a laterally compressed, keeled tail.