Insectivora


The order Insectivora is a now-abandoned biological grouping within the class of mammals. Some species have now been moved out, leaving the remaining ones in the order Eulipotyphla, within the larger clade Laurasiatheria, which makes up one of the most basic clades of placental mammals.

History

In the past, the grouping was used as a wastebasket taxon for a variety of small to very small, relatively unspecialised mammals that feed upon insects. Since any primitive-looking fossil group of placental mammals was commonly assigned to this order for convenience, it was held to constitute the basal stock out of which other placental orders had evolved. Therefore, at its widest extent, the order Insectivora represented an evolutionary grade rather than a clade.
Taxonomy has been refined in recent years, and treeshrews, elephant shrews, and colugos have now been placed in separate orders, as have many fossil groups that were formerly included here. For some time it was held that the remaining insectivoran families constituted a monophyletic grouping, or clade, to which the name Lipotyphla had long been applied. However, molecular evidence indicated that Chrysochloridae and Tenrecidae should also be separated as a new order Afrosoricida.
Erinaceidae was then also split off into a separate order from the remainder, comprising the families Soricidae, Talpidae, Solenodontidae, and Nesophontidae. These two orders then replaced Insectivora. This scheme was undermined when molecular studies indicated that Soricomorpha is paraphyletic, because Soricidae shared a more recent common ancestor with Erinaceidae than with other soricomorphs.
However, the combination of Soricidae and Erinaceidae, referred to as order Eulipotyphla, has been shown to be monophyletic.

Classification

Family-level cladogram of extant insectivoran relationships, following Roca et al.:
These families have been placed within Insectivora in the past:
Not to be confused with insectivores, many of which do not belong to Eulipotyphla or the other taxa formerly included within Insectivora.

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