(ĭnsĕk´t vōr´´)
, term broadly given to any insect-eating animal or plant. More specifically, the term refers to mammals of the order Insectivora (see Chordata), including the shrew, mole, hedgehog, tenrec, and solenodon. Insectivores are small animals, ranging from 2 to 16 in. (5—40 cm) in length; they are generally quite active, and most of them are nocturnal. They feed on a variety of small animals, particularly worms and insects. Members of this group are thought to be closely related to the earliest placental mammals. The tenrecs have certain anatomical features in common with the more primitive pouched, or marsupial, mammals. The other groups of placental mammals, including the primates, the order to which man belongs, are thought to have evolved as radiations from a primitive insectivore stock. The tree-shrews were formerly classified as insectivores, but are now usually classified as primates; they represent a transitional form between the two groups. Primitive insectivores may have been arboreal, e.g., the tree shrew, but modern forms are ground or even underground dwellers; the mole is highly specialized for subterranean life. Insectivores are found in the Old and New Worlds from subarctic regions to the tropics, but there are none in Australia, New Guinea, New Zealand, or most of South America.
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