Insectivora

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in biology, Insectivora It is a type of small animal. Now divided into Erinaceomorpha, African hedgehogs and shrews. The order Insectivora is the earliest and most primitive order in the subclass Eutheria of the class Mammalia. Insectivorous animals have appeared in the Cretaceous strata of the Mesozoic Era. It is generally believed that the order Carnivora, Chiroptera, and Rodents were all differentiated from the early insectivores. Basically, they are shrews, moles and hedgehogs. The life span of insectivores is generally not long. Shrews can only live for 6 weeks. If they don’t eat for a few hours, they will die due to their inability to maintain body temperature. The longest hedgehogs can only live In about 10 years, insectivores can control some insect pests, but some species can also transmit diseases such as plague and malaria.

The family Hedgehogidae has now been moved out of the order Insectivora and classified as Erinaceomorpha.

The body is small, the snout is thin and pointed, it can move flexibly, and the brain has no grooves. The incisors are large and pincer-shaped, the canines are small or absent, and the molars are multi-pointed with mostly W-shaped tips, which are suitable for eating insects. The limbs are short, usually with 5 toes, and are plantigrade.

Insectivora animals are small placental animals whose bodies are covered with soft hairs or hard spines and look like small mice.

Almost widely distributed throughout the world (except Oceania and Antarctica). In South America, it is only found in the northernmost part of South America.

Lifestyles are diverse, including living on the ground, living in underground caves, semi-aquatic and arboreal.

Most members of Insectivora are highly adapted to the insectivorous life and are efficient hunters. Some types of saliva are toxic and can easily subdue opponents. Their food is generally animal-based, such as invertebrates, insects, small frogs, snakes, lizards, small fish, etc. They also eat some fruits.

Before the era of widespread DNA sequencing, the grouping was used as a polyphyletic 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 (golden moles), Tenrecidae (tenrecs), and Potamogalidae (otter shrews) should also be separated as a new order Afrosoricida.

Erinaceidae (hedgehogs) was then also split off into a separate order (Erinaceomorpha) from the remainder (termed Soricomorpha), comprising the families Soricidae (shrews), Talpidae (moles), 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.