Why are animals classified in the family Erinaceidae?

Answer 1

Modern erinaceids are split into two quite distinct subgroups, the spiny hedgehogs (subfamily Erinaceinae) and the soft-furred gymnures (known most correctly as subfamily Hylomyinae, but also often referred to as Echinosorinae or Galericinae). Within the hedgehogs there are 14 species in five well-described genera. The taxonomy of the gymnures is rather less clear-cut. There are seven species, including the long-eared lesser gymnure (Hylomys megalotis), which was described in 2002. Prior to 1991, there were five recognized genera, but Neohylomys and Neotetracus have since been reclassified as subgenera of Hylomys. As of 2002, Hylomys is the largest genus in the family with five species, but these are highly variable and the expectation is that further revisions will come.