Shrew in the context of "Tenrecidae"

A mammal (from Latin mamma 'breast') is a vertebrate animal of the class Mammalia (/məˈmeɪli.ə/). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors diverged in the Carboniferous Period over 300 million years ago. Around 6,640 extant species of mammals have been described and divided into 27 orders. The study of mammals is called mammalogy.

The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the even-toed ungulates (including pigs, bovids and whales), and the Carnivora (including cats, dogs, and seals).

Elephant shrews, also called jumping shrews or sengis, are small insectivorous mammals native to Africa, belonging to the family Macroscelididae, in the order Macroscelidea. Their traditional common English name "elephant shrew" comes from a perceived resemblance between their long noses and the trunk of an elephant, and their superficial similarity with shrews (family Soricidae) in the order Eulipotyphla. However, phylogenetic analysis has revealed that elephant shrews are not properly classified with true shrews, but are in fact more closely related to elephants than to shrews. In 1997, the biologist Jonathan Kingdon proposed that they instead be called "sengis" (singular sengi), a term derived from the Bantu languages of Africa, and in 1998, they were classified into the new clade Afrotheria.

They are widely distributed across the southern part of Africa, and although common nowhere, can be found in almost any type of habitat, from the Namib Desert to boulder-strewn outcrops in South Africa to thick forest. One species, the North African elephant shrew, remains in the semi-arid, mountainous country in the far northwest of Africa. The Somali elephant shrew went unobserved from 1968 to 2020 but was rediscovered by a group of scientists in Djibouti.

A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are 17 species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introduction. There are no hedgehogs native to Australia and no living species native to the Americas. However, the extinct genus Amphechinus was once present in North America.

Hedgehogs share distant ancestry with shrews (family Soricidae), with gymnures possibly being the intermediate link, and they have changed little over the last 15 million years. Like many of the first mammals, they have adapted to a nocturnal way of life. Their spiny protection resembles that of porcupines, which are rodents, and echidnas, a type of monotreme.

An insectivore is a carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects.

The first vertebrate insectivores were amphibians. When they evolved 400 million years ago, the first amphibians were piscivores, with numerous sharp conical teeth, much like a modern crocodile. The same tooth arrangement is however also suited for eating animals with exoskeletons, thus the ability to eat insects can stem from piscivory.