Microgale brevicaudatashort-tailed shrew tenrec

Geographic Range

Microgale brevicaudata is endemic to the island of Madagascar. It is not migratory so it remains on this island permanently. Scientists believe that M. brevicaudata and other species reached Madagascar by floating on rafts of material. Madagascar split from continental Africa 100 million years ago, well before the development of most groups of mammals. (Fons, 1988; Olsen, 1997)

Habitat

M. brevicaudata lives primarily in rainforests and humid forests. However, it has been recorded in shrubby areas, grasslands, marshes, and agricultural fields in the highlands of Madagascar. This species has not been extensively studied so there is not much habitat data available. However, other species of the same genus appear to survive in small forest habitats of 35 hectares. (Fons, 1988; Garbutt, 1999; Walker, 1964)

  • Range elevation
    1200 to 1500 m
    3937.01 to 4921.26 ft

Physical Description

M. brevicaudata is a small, shrew-like tenrec. It weighs 7 to 12 grams and is 6.6 to 7 centimeters long. Its tail length is 3.3 cm. It is dark brown with a grey throat and abdomen and there are fine rings on its short tail. It has very sparse hair but its fur is soft. It has large, projecting, grey-purple ears. All limbs have 5 digits and it walks plantigrade. The fore limbs are shorter than the hind ones. Its tail is prehensile. The genus is unusual in having 47 vertebrae, more than any other tenrec. (Fons, 1988; Vaughan, et al., 2000; Walker, 1964)

Both males and females have a cloaca. The male has a retractile penis with a baculum. For the genus Microgale the testes are located in the pelvis and that position does not change before mating. (Fons, 1988; Vaughan, et al., 2000; Walker, 1964)

Members of the family Tenrecidae do not have a complete zygomatic arch because the jugal bone is absent. These animals have W-shaped ectoloph molars and a dental formulaof 2/3, 1/1, 3/3, 4/3 for a total of 40 teeth. (Fons, 1988; Vaughan, et al., 2000; Walker, 1964)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    7 to 12 g
    0.25 to 0.42 oz
  • Range length
    6.6 to 7 cm
    2.60 to 2.76 in

Reproduction

There has been no research done on the mating of M. brevicaudata, but other members of the same genus are polygynandrous. There is evidence that tenrecs may use sound to communicate with potential mates. (Fons, 1988; Garbutt, 1999; Vaughan, et al., 2000; Walker, 1964)

Very little is known about the reproductive behavior of M. brevicaudata. Some things yet to be researched are gestation period, weight of young per birth, age of sexual maturity, and age of weaning. The brood size can be 1 to 8. Members of the same genus have reproductive cycles that closely match the wet and dry seasons of Madagascar. Other members of the genus Microgale have a gestation period of about 58 to 64 days and their young sexually matures at 8.5 to 14 weeks. M. brevicauda is probably similar to other members of the genus in this regard. (Fons, 1988; Garbutt, 1999; Walker, 1964)

  • Breeding interval
    The breeding interval of these animals has not been reported.
  • Breeding season
    These tenrecs probably breed in November through December.
  • Range number of offspring
    1 to 8

There has been no specific research done on the parental investment for M. brevicaudata. However, members of the genus Microgale rely on the female for parental care. She provides milk, warmth, and protection for the young. In members of the same genus, the average age of weaning is 22 months. The role of males in parental care has not been reported. (Walker, 1964)

  • Parental Investment
  • altricial
  • female parental care
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

Although the lifespan for M. brevicaudata is not known, a member of the same genus lived to be 13 years in captivity. However, 5 to 6 years is more likely in the wild. It is likely that M. brevicaudata is similar to other members of the genus in this regard. (Walker, 1964)

Behavior

M. brevicaudata is active during the day and the night. There is some research that suggests that it is semi-fossorial. There is also some evidence to suggest that other members of the family Tenrecidae use clicks for echolocation, however this has not been studied in M. brevicaudata. Like all mammals as small as M. brevicaudata, these tenrecs must eat constantly to survive. There is evidence that members of the same genus undergo torpor, however M. brevicaudata does not. Although some members of Microgale are aquatic, there is no evidence to suggest M. brevicaudata is. Most tenrecs are solitary creatures and interact only to mate and raise young. (Fons, 1988; Garbutt, 1999; Vaughan, et al., 2000; Walker, 1964)

Home Range

The size of the home range of these animals has not been reported.

Communication and Perception

M. brevicaudata has been heard making squeals and whimpering noises, however not much is known how this is used for communication. Tenrecs in general do use scent signals and a primitive type of sonar. It is possible M. brevicaudata communicates with ultrasonic frequencies. (Walker, 1964)

Like other diurnal mammals, it is likley that these tenrecs use some visual signals to communicate. Tactile communication is probably used between mates, as well as between mothers and their offspring.

Food Habits

M. brevicaudata is insectivorous, eating insects and small vertebrates. It eats during the day and the night. It may dig through the soil looking for food, but mostly just wanders around eating what is available. (Fons, 1988; Vaughan, et al., 2000; Walker, 1964)

  • Animal Foods
  • insects
  • terrestrial non-insect arthropods

Predation

M. brevicaudata is preyed upon by birds of prey, small carnivores, and reptiles. Although it makes sounds when threatened, it has no system of defense other than running away. (Fons, 1988; Walker, 1964)

Ecosystem Roles

There is no information regarding the impact of M. brevicaudata on the ecosystem. However, since it is insectivorous, it may have an impact on the insect populations. To the extent that it serves as prey for other species, it may also affect predator populations. (Fons, 1988)

Economic Importance for Humans: Positive

M. brevicaudata offers no economic importance for humans. (Goodman and Rakotondravony, 1999)

Economic Importance for Humans: Negative

M. brevicaudata has no negative importance for human economies.

Conservation Status

M. brevicaudata is under no special conservation status.

Other Comments

The family Tenrecidae is most closely related to the family Chrysochloridae. The genus Microgale is most closely related to its sister genus, Oryzorictes. This is according to the latest molecular data. (Grenyer and Purvis, 2002)

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Adam Mileski (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
echolocation

The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

insectivore

An animal that eats mainly insects or spiders.

island endemic

animals that live only on an island or set of islands.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

marsh

marshes are wetland areas often dominated by grasses and reeds.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

ultrasound

uses sound above the range of human hearing for either navigation or communication or both

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

Fons, R. 1988. Living Insectivores. Pp. 430-448 in Grzimek's Encylopedia of Mammals, Vol. 1, 1 Edition. New York: McGraw-Hill Publishing.

Garbutt, N. 1999. Mammals of Madagascar. Hong Kong: Pica Press.

Goodman, S., D. Rakotondravony. 1999. The effects of forest fragmentation and isolation on insectivorous small mammals (Lipotyphla) on the Central High Plateau of Madagascar. The Journal of Zoology, 250: 193-200.

Grandidier, G. 2003. "System Naturae 2000" (On-line). Accessed March 24, 2004 at http://sn2000.taxonomy.nl/Main/Classification/60694.htm.

Grenyer, R., A. Purvis. 2002. A composite species-level phylogeny of the 'Insectivora' (Mammalia: Order Lipotyphla Haeckel, 1866). The Journal of Zoology, 260: 245-257.

Olsen, L. 1997. Tenrecs---an example of evolution in isolation. In The Field, 68(3): 1.

Vaughan, T., J. Ryan, N. Czaplewski. 2000. Mammology Fourth Edition. United States of America: Thomson Learning.

Walker, E. 1964. Mammals of the World Volume 1. Baltimore: The Johns Hopkins Press.