A tenrec in defensive mode, Horniman Museum, London

A tenrec is any species of

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur ...

within the

afrotheria Afrotheria ( from Latin ''Afro-'' "of Africa" + ''theria'' "wild beast") is a clade of mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews (also k ...

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Tenrecidae endemic to

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Afric ...

. Tenrecs are wildly diverse; as a result of

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...

some resemble

hedgehog A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introductio ...

shrew Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to differ ...

opossum Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered No ...

s, rats, and

mice A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus'' ...

. They occupy aquatic,

arboreal Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. The habitats pose nu ...

, terrestrial and

fossorial A fossorial () animal is one adapted to digging which lives primarily, but not solely, underground. Some examples are badgers, naked mole-rats, clams, meerkats, and mole salamanders, as well as many beetles, wasps, and bees. Prehistoric evid ...

environments. Some of these species, including the greater hedgehog tenrec, can be found in the

Madagascar dry deciduous forests The Madagascar dry deciduous forests represent a tropical dry forest ecoregion situated in the western and northern part of Madagascar. The area has high numbers of endemic plant and animal species but has suffered large-scale clearance for agric ...

. However, the speciation rate in this group has been higher in humid forests. All tenrecs are believed to descend from a common ancestor that lived 29–37 million years ( Ma) ago after

rafting Rafting and whitewater rafting are recreational outdoor activities which use an inflatable raft to navigate a river or other body of water. This is often done on whitewater or different degrees of rough water. Dealing with risk is often a ...

over from Africa. The split from their closest relatives, African

otter shrew Potamogalidae is the family of "otter shrews", a group of semiaquatic riverine afrotherian mammals indigenous to sub-Saharan Africa. They are most closely related to the tenrecs of Madagascar, from which they are thought to have split about 47� ...

s, is estimated to have occurred about 47–53 Ma ago.

Etymology

The word ''tenrec'' is borrowed, via

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

, from the Malagasy word (variant of ), which refers to the Tailless tenrec (''Tenrec ecaudatus''); the Malagasy word is related to .

Evolution

Tenrecs are believed to have evolved from a single species that colonized Madagascar between 42 and 25 million years ago. The question of how this family reached Madagascar is still unclear, but the leading hypothesis suggests a small number of individuals may have found themselves on floating vegetation and crossed the Mozambique Channel, which separates Madagascar from southeastern Africa. The family Tenrecidae is one of only four extant terrestrial mammal lineages to have colonized and diversified on Madagascar. Once established on Madagascar, tenrecs diversified to occupy various niches on the island. Many evolved resemblances to familiar but unrelated mammals that are not found on Madagascar. For example, the two species of hedgehog tenrec possess coats of hardened spines and the ability to roll into a ball when threatened; characteristics similar to those of true

s. This example, along with others, demonstrates convergent evolution, and has provided evolutionary biologists with opportunities to study adaptation over evolutionary timescales.

Characteristics

Tenrecs are small mammals of variable body form. The smallest species are the size of shrews, with a body length of around , and weighing just , while the largest, the common or tailless tenrec, is in length, and can weigh over . Although they may resemble shrews, hedgehogs, or opossums, they are not closely related to any of these groups, their closest relatives being the

s, and after that, other African insectivorous mammals, such as

golden mole Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They comprise the family Chrysochloridae and as such they are taxonomically distinct from the true moles, family Talpidae, and other mole-like families, all ...

s and elephant shrews. The common ancestry of these animals, in the group

Afrotheria Afrotheria ( from Latin ''Afro-'' "of Africa" + ''theria'' "wild beast") is a clade of mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews (also k ...

, was not recognized until the late 1990s. Continuing work on the molecular and morphological diversity of afrotherian mammals has provided ever increasing support for their common ancestry. Unusually among placental mammals, the

anus The anus (Latin, 'ring' or 'circle') is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, the residual semi-solid waste that remains after food digestion, which, ...

and

urogenital tract The genitourinary system, or urogenital system, are the organs of the reproductive system and the urinary system. These are grouped together because of their proximity to each other, their common embryological origin and the use of common pathwa ...

s of tenrecs share a common opening, or

cloaca In animal anatomy, a cloaca ( ), plural cloacae ( or ), is the posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles and birds, ...

, a feature more commonly seen in

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates ( lizards and snakes) and rhynchocephalia ...

s, and

amphibian Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbo ...

s. They have a low

body temperature Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperatur ...

, sufficiently so that they do not require a

scrotum The scrotum or scrotal sac is an anatomical male reproductive structure located at the base of the penis that consists of a suspended dual-chambered sac of skin and smooth muscle. It is present in most terrestrial male mammals. The scrotum co ...

to cool their

sperm Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, ...

as do most other mammals. All species appear to be at least somewhat

omnivorous An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nut ...

, with

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chorda ...

s forming the largest part of their diets. One species, ''Microgale mergulus'', is

semiaquatic In biology, semiaquatic can refer to various types of animals that spend part of their time in water, or plants that naturally grow partially submerged in water. Examples are given below. Semiaquatic animals Semi aquatic animals include: * Ve ...

(similar to the lifestyle of their closest relatives, the otter shrews). All of the species, semiaquatic or not, appear to have evolved from a single, common ancestor, with the otter shrews comprising the next, most-closely related mammalian species. While the fossil record of tenrecs is scarce, at least some specimens from the early

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

of Kenya show close affinities to living species from Madagascar, such as ''Geogale aurita''. Most species are

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

and have poor eyesight. Their other senses are well developed, however, and they have especially sensitive

whiskers Vibrissae (; singular: vibrissa; ), more generally called Whiskers, are a type of stiff, functional hair used by mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarse ...

. As with many of their other features, the

dental formula Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiolog ...

of tenrecs varies greatly between species; they can have from 32 to 42 teeth in total. Unusual for mammals, the permanent dentition in tenrecs tends not to completely erupt until well after adult body size has been reached. This is one of several anatomical features shared by elephants,

hyrax Hyraxes (), also called dassies, are small, thickset, herbivorous mammals in the order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Typically, they measure between long and weigh between . They are superficially simila ...

es, sengis, and

s (but apparently not aardvarks), consistent with their descent from a common ancestor. Tenrecs have a

gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pr ...

period of 50 to 64 days, and give birth to a number of relatively undeveloped young. While the

s have just two young per litter, the tailless tenrec can have as many as 32, and females possess up to 29 teats, more than any other mammal. At least some tenrec species are social, living in multigenerational family groups with over a dozen individuals.

Interaction with humans

In the island nation of

Mauritius Mauritius ( ; french: Maurice, link=no ; mfe, label= Mauritian Creole, Moris ), officially the Republic of Mauritius, is an island nation in the Indian Ocean about off the southeast coast of the African continent, east of Madagascar. It ...

, and also on the Comoran island of

Mayotte Mayotte (; french: Mayotte, ; Shimaore: ''Maore'', ; Kibushi: ''Maori'', ), officially the Department of Mayotte (french: Département de Mayotte), is an overseas department and region and single territorial collectivity of France. It is loca ...

, some of the inhabitants eat tenrec meat, though it is difficult to obtain (as it is not sold in shops or markets) and difficult to prepare correctly. The

lesser hedgehog tenrec The lesser hedgehog tenrec (''Echinops telfairi'') is a species of mammal in the family Tenrecidae. It is the only species in the genus ''Echinops'' and is named in honour of Charles Telfair. It is endemic to Madagascar. Its natural habitats a ...

(''Echinops telfairi'') is one of 16 mammalian species that will have its genome sequenced as part of the Mammalian Genome Project. It is increasingly popular in the pet trade, and in the future may serve as an important model organism in biomedicine, as it is only distantly related to the mice, rats, guinea pigs, and rhesus macaques that comprise the most common research animals.

Threats

Of the 31 species assessed, 24 (77%) are categorized by the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biolo ...

as Least Concern, 1 species as Data Deficient, 4 species as Vulnerable, and 2 species as Endangered. The conservation status of many tenrec species is of concern due to an increase of threats within the last 50 years. The main threats facing tenrecs include habitat loss due to

deforestation Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated ...

, fragmentation and degradation, hunting, incidental capture, and climate change.

Slash-and-burn Slash-and-burn agriculture is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden. The method begins by cutting down the trees and woody plants in an area. The downed veget ...

agriculture, as well as commercial logging and mining of metals is negatively affecting tenrec species that inhabit forests. Five of the six threatened Tenrec species are dependent on forest habitats.

Conservation

As of 2022, conservation of the tenrec population is not being prioritized. Because most tenrecs are dependent on forest habitats, conservation efforts would need to include a focus on reduction in deforestation on Madagascar as well as habitat restoration. Current conservation efforts include that of the Madagascar Ankizy Fund, started by a paleontological team from

Stony Brook University Stony Brook University (SBU), officially the State University of New York at Stony Brook, is a public research university in Stony Brook, New York. Along with the University at Buffalo, it is one of the State University of New York system' ...

to improve access to health care and education facilities for villagers in remote areas of Madagascar. A healthy and educated local human population will, in the long term, benefit the Malagasy fauna, such as tenrecs.

Species

The three subfamilies, eight genera, and 31 extant species of tenrecs are: FAMILY TENRECIDAE * Subfamily Geogalinae ** Genus ''

Geogale The large-eared tenrec (''Geogale aurita'') is a species of mammal in the family Tenrecidae. It is the only species in the monotypic genus ''Geogale'', and the only member of the subfamily Geogalinae. It is endemic to Madagascar where its natura ...

'' *** Large-eared tenrec (''Geogale aurita'') * Subfamily Oryzorictinae ** Genus ''

Microgale ''Microgale'' is a genus of mammal in the family Tenrecidae. There are 21 living species on the island of Madagascar and one extinct species known from a fossil. Some species have been discovered in the last twenty years. On the basis of molecul ...

'' *** Short-tailed shrew tenrec (''Microgale brevicaudata'') ***

Cowan's shrew tenrec Cowan's shrew tenrec (''Microgale cowani'') is a species of mammal in the family Tenrecidae. Description Cowan's shrew tenrecs weigh an average just over , and have an average length of slightly over . Most specimens are mostly brown, often ...

(''Microgale cowani'') ***

Drouhard's shrew tenrec Drouhard's shrew tenrec (''Microgale drouhardi''), also known as the striped shrew tenrec, is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical and tropical moist lowland and montan ...

(''Microgale drouhardi'') ***

Dryad shrew tenrec The dryad shrew tenrec (''Microgale dryas''), also known as the tree shrew tenrec, is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitat is subtropical or tropical moist lowland forests. References

...

(''Microgale dryas'') ***

Pale shrew tenrec The pale shrew tenrec (''Microgale fotsifotsy''), also known as the pale-footed shrew tenrec is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical and tropical moist lowland and monta ...

(''Microgale fotsifotsy'') *** Gracile shrew tenrec (''Microgale gracilis'') ***

Grandidier's shrew tenrec ''Microgale grandidieri'', also known as Grandidier's shrew tenrec, is a species of shrew tenrec occurring in the dry forests of western and southwestern Madagascar. Populations of this species were formerly included in '' Microgale brevicaudata ...

''(Microgale grandidieri)'' ***

Naked-nosed shrew tenrec The naked-nosed shrew tenrec (''Microgale gymnorhyncha'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical and tropical moist lowland and monaten forests. References ...

(''Microgale gymnorhyncha'') ***

Jenkins's shrew tenrec Jenkins's shrew tenrec (''Microgale jenkinsae'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical or tropical dry forests and shrubland. It is threatened by habitat loss. Descrip ...

(''Microgale jenkinsae'') ***

Northern shrew tenrec The northern shrew tenrec (''Microgale jobihely'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar, where it has a restricted disjoint range in two locations 485 km apart in the north and east of the island. In ...

(''Microgale jobihely'') ***

Lesser long-tailed shrew tenrec The lesser long-tailed shrew tenrec (''Microgale longicaudata'') is a species of mammal in the family Tenrecidae. It is active at all hours of the day and night, but each individual maintains its own pattern of rest and activity. Range and Hab ...

(''Microgale longicaudata'') *** '' Microgale macpheei'' (extinct) ***

Major's long-tailed tenrec Major's long-tailed tenrec (''Microgale majori'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitat is the eastern humid forest of the island, as well as some western forests, where it has been see ...

(''Microgale majori'') ***

Web-footed tenrec The web-footed tenrec, Malagasy otter shrew, or aquatic tenrec (''Microgale mergulus'') is the only known semiaquatic tenrec (the related African otter shrews have similar habits), and is found in eastern Madagascar, especially in and around Rano ...

(''Microgale mergulus'') ***

Montane shrew tenrec The montane shrew tenrec (''Microgale monticola'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitat is subtropical or tropical moist montane forest Montane ecosystems are found on the slopes ...

(''Microgale monticola'') ***

Nasolo's shrew tenrec Nasolo's shrew tenrec (''Microgale nasoloi'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical or tropical moist montane Montane ecosystems are found on the slopes of mountai ...

(''Microgale nasoloi'') ***

Pygmy shrew tenrec The pygmy shrew tenrec (''Microgale parvula'') is a species of placental mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitat is subtropical or tropical moist forests. While it is not endangered, its population is sl ...

(''Microgale parvula'') ***

Greater long-tailed shrew tenrec The greater long-tailed shrew tenrec (''Microgale principula'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar, where its natural habitats are subtropical or tropical moist forests. Distribution and habitat The gre ...

(''Microgale principula'') ***

Least shrew tenrec The least shrew tenrec (''Microgale pusilla'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links= ...

(''Microgale pusilla'') ***

Shrew-toothed shrew tenrec The shrew-toothed shrew tenrec (''Microgale soricoides'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasik ...

(''Microgale soricoides'') *** Taiva shrew tenrec (''Microgale taiva'') ***

Thomas's shrew tenrec Thomas's shrew tenrec (''Microgale thomasi'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=n ...

(''Microgale thomasi'') ** Genus '' Nesogale'' ***

Dobson's shrew tenrec Dobson's shrew tenrec (''Nesogale dobsoni'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical or tropical moist forests, plantations, and heavily degraded former forest. On the ba ...

(''Nesogale dobsoni'') ***

Talazac's shrew tenrec Talazac's shrew tenrec (''Nesogale talazaci'') is a species of mammal in the family Tenrecidae. It is endemic to Madagascar. Its natural habitats are subtropical or tropical moist forests. On the basis of molecular data indicating that it and Do ...

(''Nesogale talazaci'') ** Genus '' Oryzorictes'' *** Mole-like rice tenrec (''Oryzorictes hova'') *** Four-toed rice tenrec (''Oryzorictes tetradactylus'') * Subfamily Tenrecinae ** Genus ''

Echinops ''Echinops'' is a genus of about 120 species of flowering plants in the family Asteraceae, commonly known as globe thistles. They have spiny foliage and produce blue or white spherical flower heads. They are native to Europe, east to central As ...

'' ***

Lesser hedgehog tenrec The lesser hedgehog tenrec (''Echinops telfairi'') is a species of mammal in the family Tenrecidae. It is the only species in the genus ''Echinops'' and is named in honour of Charles Telfair. It is endemic to Madagascar. Its natural habitats a ...

(''Echinops telfairi'') ** Genus '' Hemicentetes'' *** Highland streaked tenrec (''Hemicentetes nigriceps'') ***

Lowland streaked tenrec The lowland streaked tenrec (''Hemicentetes semispinosus'') is a small tenrec found in Madagascar. It belongs to the family Tenrecidae in the order Afrosoricida, and more specifically to the subfamily of the spiny tenrecs Tenrecinae. Its natural ...

(''Hemicentetes semispinosus'') ** Genus '' Setifer'' *** Greater hedgehog tenrec (''Setifer setosus'') ** Genus '' Tenrec'' *** Common tenrec (''Tenrec ecaudatus'')

References

External links

Bizarre mammals filmed calling using their quills
at BBC Online, video with commentary by Sir

David Attenborough Sir David Frederick Attenborough (; born 8 May 1926) is an English broadcaster, biologist, natural historian and author. He is best known for writing and presenting, in conjunction with the BBC Natural History Unit, the nine natural histo ...

*
Podcast about hibernation which focusses on tenrecs in the last third.
{{Authority control Afrosoricida Extant Eocene first appearances Animals that use echolocation Taxa named by John Edward Gray