The order Insectivora was reserved for organisms observed eating insects. Linnaeus listed three families in this category: Talpidae (Old World moles), Erinaceidae (hedgehogs), and Soricidae (long-tailed shrews). Today, the order Insectivora consists of seven families: the Erinaceidae, with seven genera and 21 species of gymnures and hedgehogs; the Chrysochloridae includes seven genera and 18 species of golden moles; the Tenrecidae features ten genera and 24 species of tenrecs; the Solenodontidae consists of one genera and three species of solenodons; the Nesophontidae has one genus, Nesophontes, and six species of extinct West Indian shrews; the Soricidae includes 24 genera and 311 species of shrews; and the Talpidae features 17 genera and 41 species of moles, shrew moles, and desmans.
The order Insectivora has 426 species of small mammals, three-fourths of which are shrews, quite possibly the smallest of all mammals. The Insectivora is the third largest order of mammals. The Rodentia is the largest with over 2,000 species and the Chiroptera (bats) is the second with over 900 species.