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Jenkins's shrew tenrec (''Microgale jenkinsae'') is a species of mammal in the family Tenrecidae. It is
endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...
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 Africa ...
. Its natural habitats are subtropical or tropical dry forests and
shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It ...
. It is threatened by
habitat loss Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
.


Description

Jenkins's shrew tenrec is extremely small, 143-147mm with the tail being 71-81mm . Its fur is extremely dense, with the top of it being tannish-brown with darker flecks from their
agouti gene Agouti-signaling protein is a protein that in humans is encoded by the ASIP gene. It is responsible for the distribution of melanin pigment in mammals. Agouti interacts with the melanocortin 1 receptor to determine whether the melanocyte (pigment ...
. On the bottom it is a paler grizzled slate-gray. The tail of this Tenrec is dark brown on the top, and much lighter on the bottom.


Habitat

This tenrec is restricted to the Mikea Forest between Morombe and Manobo River in Southwest Madagascar. It is generally found in forest habitats. The forest of this region grows on sandy soil and in a semi-arid climate with annual precipitation as low as 350 mm. The canopy, which rarely exceeds twelve meters in height, is less tall than that of the inland forests and of those further north. Its habitat exhibits a tropical dry climate with a distinct dry season between May and October. During the wet season, November to April, rainfall may reach 750 millimetres (mm), within a yearly range of 575 mm to 1330 mm. The annual average daily temperature for the region is between 25 °C and 31 °C.


Ecological threats

The Mikea forest is threatened by both intentional burning for expansion of agricultural lands and unintentional wildfires as well as deforestation for commodity lumber. The
overexploitation Overexploitation, also called overharvesting, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to replenish. The term ap ...
of trees is a major factor to the ecology of the mike forest because many trees here are in high demand in the construction industry. These trees include the ''Givotia madagascariense'', ''Cedrelopsis grevei'', and ''Commifora arofy''. All are endemic to Madagascar and the high demand for them in the
construction industry Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and ...
directly threatens the ecology of the Mikea forest.


Conservation

The main threat to Jenkins's shrew tenrec's is habitat loss from wildfires and intentional burning and thus steps must be taken to ensure that the Mikea Forest is not completely lost. It is not currently within a protected area, however, the Mikea Forest is in the process of becoming a protected area. Further research is needed into the population, biology, ecology, range and adaptation to disturbance. Currently research is being conducted to determine possible solutions to minimize deforestation in the region. Organizations such as the World Wildlife Fund are concerned with the conservation of the habitat of Jenkins' shrew tenrec because it is also home to a plethora of other species.


Taxonomy

''Microgale jenkinsae'' is placed with the family Tenrecidae. Members of this family "do not have a wide geographic distribution. They are most numerous and diverse on the island of Madagascar, but a few species are also found in western central Africa." Various species in the family are similar to "hedgehogs, shrews, opossums, mice and even otters; and members of the family occupy a diverse collection of habitats, including aquatic, arboreal, terrestrial and fossorial," this is 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 ...
. The family Tenrecidae reached Madagascar 60 million years ago when, "a small mammal, perhaps no more than 5 or 6 g in weight with a primitive body plan and physiology, was washed out to sea from Africa," and rafted over, much like the original lemurs of Madagascar. It is still unknown whether others joined this one, or this one was a pregnant female. Madagascar at the time had few to no other mammals present, except for other small mammals that floated over, to compete with the tenrecs, resulting in an
adaptive radiation In evolutionary biology, adaptive radiation is a process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, alters biotic int ...
. This process resulted in
speciation Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution withi ...
from the original tenrec into 34 different species, one of them being Jenkin’s shrew tenrec. The species is part of the subfamily
Oryzorictinae Oryzorictinae is a subfamily of tenrecs endemic to the island of Madagascar. It is the largest of three tenrec subfamilies. Oryzorictinae is thought to have split from the lineage of its closest relative, '' Geogale'', about 30 million years ( M ...
, which consists of tenrecs endemic to Madagascar. Its genus is ''Microgale''. There are 22 living species of ''Microgale'' on the island of Madagascar. The specific epithet ''jenkinsae'' honours the British mammalogist
Paulina D. Jenkins Paulina (Paula) D. Jenkins – active from the 1970s – is a British zoologist, specialising in mammals and employed as curator at the Natural History Museum, London. Jenkins has published research in a large number of papers, especially on small ...
.


Diet

Tenrecs are often referred to as insectivorous, but a more appropriate term is faunivorous, meaning they eat a diverse variety of animals (and not just insects). Most tenrecs eat terrestrial invertebrates, although several species will opportunistically eat other small vertebrates such as amphibians, reptiles, birds, rodents, and other tenrecs. Some species are known to eat carrion. Despite such similar diets, there have been 14 tenrec species recorded within the same locality and up to 11 shrew tenrecs alone sharing the same habitat. How they partition prey within such an apparently crowded community of small-bodied faunivores remains unknown and has proven to be a challenging question to answer.


References

{{Taxonbar, from=Q2700154 Afrosoricida Mammals of Madagascar Mammals described in 2004 Taxonomy articles created by Polbot