In the past, the grouping was used as a scrapbasket for a variety of small to very small, relatively unspecialised, insectivorous mammals. Since any primitive-looking fossil groups of placental mammals were commonly assigned to this order for convenience, it was held to constitute the basal stock out of which other placental orders had evolved. At its widest extent, therefore, the order Insectivora was polyphyletic and cannot be considered a clade.
The 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 (golden moles) and Tenrecidae (tenrecs) also should be separated as a new order Afrosoricida. The species remaining in the clade Insectivora were then referred to as order Eulipotyphla. After further scrutiny, other evidence now indicates that even Erinaceidae (hedgehogs) should also be placed in a separate order from the remainder, comprising the families Soricidae (shrews), Talpidae (moles), Solenodontidae and Nesophontidae. These two orders, Erinaceomorpha and Soricomorpha, now replace Insectivora. Molecular studies indicate that Soricomorpha is paraphyletic, because Soricidae shared a more recent common ancestor with Erinaceidae than with other soricomorphs.
- ORDER INSECTIVORA
- Family Erinaceidae
- Family Soricidae
- Subfamily Crocidurinae: white-toothed shrews
- Subfamily Soricinae: red-toothed shrews
- Subfamily Myosoricinae: African white-toothed shrews
- Family Talpidae
- Subfamily Desmaninae: desmans
- Subfamily Talpinae: moles
- Subfamily Uropsilinae: shrew moles
- Family Solenodontidae: solenodons
- Family Nesophontidae: extinct West Indian shrews
Family-level cladogram of extant insectivoran relationships, following Roca et al.:
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These families have been placed within Insectivora in the past:
- * Family Chrysochloridae (golden moles)
- * Family Tenrecidae (tenrecs)
- * Family Macroscelididae (elephant shrews)
- * Family Tupaiidae (treeshrews)
- * Family Cynocephalidae (colugos)
Not to be confused with insectivores (the eaters of insects considered as an dietary behaviour), many of which belong to the Order Insectivora.
References
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Last updated on Thursday July 10, 2008 at 03:19:18 PDT (GMT -0700)
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