Common Treeshrew
Encyclopedia
The Common Treeshrew is a small mammal in the treeshrew
family Tupaiidae
, and is native to Thailand
, Malaysia and Indonesia
. It has been listed as Least Concern
by IUCN as it remains common and displays some adaptability to ongoing habitat loss.
There are two subspecies T.g. longipes and T.g. salatana, with T.g. longipes being duller in coloration than T.g. salatana. The underparts of longipes are dull buff to reddish buff, and the underside of the tail is greyish. The underparts and underside of the tail are dark reddish in salatana. Similar species are Tupaia splendidula and Tupaia montana.
. In Indonesia, they are found on the islands of Siberut
, Batu
, Sumatra
, Java
, Bangka
, Riau, Lingga and Anambas
. Usually they are found in primary dipterocarp forest, but are tolerant to some degree of habitat modification. They have also been recorded from secondary forest, plantations, fruit orchards and trees near housing areas.
This species is probably present throughout the lowlands and hills up to 1100 m (3,608.9 ft) in the Kelabit Highlands
of Borneo
. The subspecies T.g. longipes occurs in the north of Borneo, in Sarawak
, and in East Kalimantan
including Sabah
. The subspecies T.g. salatana occurs in the south of Rajang River
and Kayan River
in Borneo.
Common treeshrews inhabit protected areas, including Pasoh Forest Reserve
on the Malay Peninsula and Krau Wildlife Reserve
.
, and forage for food alone or in pairs, mainly on the ground, among shrubs and tree holes. They feed on fruits, seeds, leaves, and insects especially ants and spiders. They are also reported to catch lizards.
They are very agile in climbing both large vertical tree trunks and bushes, and occasionally jump from stems of a young tree to that of another as much as 60 cm (23.6 in) away. Their climbing is concentrated in lower heights. They frequently scent-mark their territories by chest and ano-genital rubbing with a secretion from glands on chest and scrotum
. Adult males are more secretory than females and juveniles. In the Bukit Timah Nature Reserve
, mean home ranges of adult males were estimated at 10174 m² (109,512 sq ft), of adult females at 8809 m² (94,819.3 sq ft), of juvenile males at 7527 m² (81,020 sq ft), and of juvenile females at 7255 m² (78,092.2 sq ft), with partial overlaps between male and female ranges varying from 0.4% to 56.8%. Home ranges of adult residents of the same sex overlap to a lesser degree than those of opposite sexes. A male’s range may include the ranges of two or three females. A high overlap between ranges of one adult male and one adult female indicates that they form a stable pair. Juvenile ranges of either sex adjoin or overlap with ranges of adults, suggesting that the juveniles are family members. Individuals of the same sex are involved in aggressive territorial chases.
Juvenile males depart from their family's territory sooner than juvenile females.
From October to December, common treeshrews are reproductively inactive. The mating season starts at the onset of the monsoon
season in December and lasts until February. Oestrus and pre-oestrus behavior is characterized by adult males pursuing adult females. Males emit chattering, and appear to be extremely excited. They also chase each other and fight. Females do not actively choose a partner among the male participants of chases. The dominant male gains access to females.
In tropical rainforest
habitats in West Malaysia, density of common treeshrews varies from about two to five animals per hectare. Their annual breeding coincides with the abundance of invertebrate
s after the dry season. Their main reproductive period is between February and June, and their litter size invariably two. Some females breed more than once a season, and the age at first pregnancy is seven months. The main period of emigration or mortality of young is during the breeding period or monsoon.
and Alfred Duvaucel in their jointly written article "Sur une nouvelle espèce de Sorex — Sorex Glis", which is preceded by an illustration. They observed specimens in Penang
and Singapore
, and considered them a species of Sorex
, and not as a new genus
.
Between 1821 and 1940, several zoologists described the species from other areas. The species still retains many forms of uncertain rank and validity, and is pending a detailed study. Some forms were formerly considered synonyms of Tupaia glis, some were elevated to species level. Synonyms include:
and ensuing human activities in agriculture, plantation and commercial logging. Moreover, other pressures such as hunting for food and sport can create pressure to the species.
.
Treeshrew
The treeshrews are small mammals native to the tropical forests of Southeast Asia. They make up the families Tupaiidae, the treeshrews, and Ptilocercidae, the pen-tailed treeshrews, and the entire order Scandentia. There are 20 species in 5 genera...
family Tupaiidae
Tupaiidae
Tupaiidae is one of two families of treeshrews, the other family being Ptilocercidae. It contains 4 genera and 19 species.-Taxonomy:*Order: Scandentia** Family Tupaiidae*** Genus Anathana**** Madras Treeshrew, Anathana ellioti...
, and is native to Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
, Malaysia and Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
. It has been listed as Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
by IUCN as it remains common and displays some adaptability to ongoing habitat loss.
Description
The common treeshrew is one of the largest among treeshrews. Average body length is between 16 –, and average weight is around 190g, with varying colours of reddish brown, greyish or black upper parts and whitish belly. Its long bushy tail is dark greyish brown and almost reaches the length of the body. The paws are bare with sharp nails, and there is a naked patch of skin above its long nose. Both sexes are similar. The measurements of the Tupaia glis according to 21 specimens are head- to-body length: 170mm to 235mm, tail length: 170mm to 242mm and hind foot: 45mm to 56mm. The common treeshrew usually has a pale stripe on each shoulder.There are two subspecies T.g. longipes and T.g. salatana, with T.g. longipes being duller in coloration than T.g. salatana. The underparts of longipes are dull buff to reddish buff, and the underside of the tail is greyish. The underparts and underside of the tail are dark reddish in salatana. Similar species are Tupaia splendidula and Tupaia montana.
Distribution and habitat
Common treeshrews occur south of about 10° N latitude in southern Thailand through mainland Malaysia and adjacent coastal islands to SingaporeSingapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
. In Indonesia, they are found on the islands of Siberut
Siberut
Siberut is the largest and northernmost of the Mentawai Islands, lying 150 kilometres west of Sumatra in the Indian Ocean. A part of Indonesia, the island is the most important home for the Mentawai people. The western half of the island was set aside as the Siberut National Park in 1993...
, Batu
Batu Islands
The Batu Islands are an archipelago of Indonesia located in the Indian Ocean off the west coast of Sumatra, between Nias and Siberut. The three primary islands, of approximately equal size, are Pini, Tanahmasa, and Tanahbala. There are forty-eight smaller islands, of which less than half are...
, Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
, Java
Java
Java is an island of Indonesia. With a population of 135 million , it is the world's most populous island, and one of the most densely populated regions in the world. It is home to 60% of Indonesia's population. The Indonesian capital city, Jakarta, is in west Java...
, Bangka
Bangka
Bangka can refer to:* Bangka Island, an island of Indonesia* Bangka Regency, Indonesia* Bangka Strait, a strait of Indonesia* Bangka language, spoken in Indonesia* Tagalog: bangka, an outrigger canoe* Wanhua District, Taipei City...
, Riau, Lingga and Anambas
Anambas
Anambas archipelago is a small archipelago of Indonesia, located in the South China Sea between the Malaysian mainland to the west and the island of Borneo to the east...
. Usually they are found in primary dipterocarp forest, but are tolerant to some degree of habitat modification. They have also been recorded from secondary forest, plantations, fruit orchards and trees near housing areas.
This species is probably present throughout the lowlands and hills up to 1100 m (3,608.9 ft) in the Kelabit Highlands
Kelabit Highlands
The Kelabit Highlands are a mountain range located in the northernmost part of Sarawak, on the island of Borneo. The highest mountains in this range are Mount Murud at 2,423 m , Bukit Batu Buli at 2,082 m , and Bukit Batu Lawi at 2,046 m .In the Kelabit Highlands, there are 14...
of Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
. The subspecies T.g. longipes occurs in the north of Borneo, in Sarawak
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
, and in East Kalimantan
East Kalimantan
East Kalimantan is the second largest Indonesian province, located on the Kalimantan region on the east of Borneo island. The resource-rich province has two major cities, Samarinda and Balikpapan...
including Sabah
Sabah
Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...
. The subspecies T.g. salatana occurs in the south of Rajang River
Rajang River
The Rajang River is a river in Sarawak, Malaysia. The river is located in northwest of Borneo and it originates in the Iran Mountains. The river flows approximately 563 km to the South China Sea, making it the longest river in Malaysia....
and Kayan River
Kayan River
Kayan River is a river of Borneo, Indonesia.Tributaries include the Bahau River.-References:...
in Borneo.
Common treeshrews inhabit protected areas, including Pasoh Forest Reserve
Pasoh Forest Reserve
The Pasoh Forest Reserve, a nature reserve located about 8 km from Simpang Pertang, Malaysia and around 70 km southeast of Kuala Lumpur, has a total area of 2450 hectares, with a core area of 600ha surrounded by a buffer zone. Palm oil plantations surround on three sides of the reserve...
on the Malay Peninsula and Krau Wildlife Reserve
Krau Wildlife Reserve
Krau Wildlife Reserve is the largest wildlife reserve covering 60,349 ha located in the central state of Pahang, Malaysia that was established during the British Colonial Administration. It is managed by the Department of Wildlife and National Parks, located south of Lanchang township...
.
Ecology and behavior
Common treeshrews are active during the dayDiurnal animal
Diurnality is a plant or animal behavior characterized by activity during the day and sleeping at night.-In animals:Animals that are not diurnal might be nocturnal or crepuscular . Many animal species are diurnal, including many mammals, insects, reptiles and birds...
, and forage for food alone or in pairs, mainly on the ground, among shrubs and tree holes. They feed on fruits, seeds, leaves, and insects especially ants and spiders. They are also reported to catch lizards.
They are very agile in climbing both large vertical tree trunks and bushes, and occasionally jump from stems of a young tree to that of another as much as 60 cm (23.6 in) away. Their climbing is concentrated in lower heights. They frequently scent-mark their territories by chest and ano-genital rubbing with a secretion from glands on chest and scrotum
Scrotum
In some male mammals the scrotum is a dual-chambered protuberance of skin and muscle containing the testicles and divided by a septum. It is an extension of the perineum, and is located between the penis and anus. In humans and some other mammals, the base of the scrotum becomes covered with curly...
. Adult males are more secretory than females and juveniles. In the Bukit Timah Nature Reserve
Bukit Timah Nature Reserve
The Bukit Timah Nature Reserve is a small 1.64 square kilometer nature reserve near the geographic centre of the city-state of Singapore, located on the slopes of Bukit Timah Hill, Singapore's highest hill standing at a height of 163.63 metres, and parts of the surrounding area...
, mean home ranges of adult males were estimated at 10174 m² (109,512 sq ft), of adult females at 8809 m² (94,819.3 sq ft), of juvenile males at 7527 m² (81,020 sq ft), and of juvenile females at 7255 m² (78,092.2 sq ft), with partial overlaps between male and female ranges varying from 0.4% to 56.8%. Home ranges of adult residents of the same sex overlap to a lesser degree than those of opposite sexes. A male’s range may include the ranges of two or three females. A high overlap between ranges of one adult male and one adult female indicates that they form a stable pair. Juvenile ranges of either sex adjoin or overlap with ranges of adults, suggesting that the juveniles are family members. Individuals of the same sex are involved in aggressive territorial chases.
Juvenile males depart from their family's territory sooner than juvenile females.
Reproduction
Both sexes of common treeshrews are sexually mature at the age of about 3 months. In captiity, females give birth for the first time at the age of about 4.5 months, usually in February. A postpartum oestrus results in more births in April. Their oestrus cycle is 8 to 39 days, and the gestation period lasts 40 to 52 days, after which a litter of one to three individuals is born. The new born offspring weighs about 10 to 12 grams. Females suckle their young every other day, and neglect their young as long as possible. They won’t even be able to identify their own young if they didn’t mark them with the scent produced from glands in their sternum and abdomen. Juveniles leave the nest between 25 to 35 days of age. Longevity of a captive common treeshrew has been recorded as 12 years and 5 months.From October to December, common treeshrews are reproductively inactive. The mating season starts at the onset of the monsoon
Monsoon
Monsoon is traditionally defined as a seasonal reversing wind accompanied by corresponding changes in precipitation, but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with the asymmetric heating of land and sea...
season in December and lasts until February. Oestrus and pre-oestrus behavior is characterized by adult males pursuing adult females. Males emit chattering, and appear to be extremely excited. They also chase each other and fight. Females do not actively choose a partner among the male participants of chases. The dominant male gains access to females.
In tropical rainforest
Tropical rainforest
A tropical rainforest is an ecosystem type that occurs roughly within the latitudes 28 degrees north or south of the equator . This ecosystem experiences high average temperatures and a significant amount of rainfall...
habitats in West Malaysia, density of common treeshrews varies from about two to five animals per hectare. Their annual breeding coincides with the abundance of invertebrate
Invertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s after the dry season. Their main reproductive period is between February and June, and their litter size invariably two. Some females breed more than once a season, and the age at first pregnancy is seven months. The main period of emigration or mortality of young is during the breeding period or monsoon.
Taxonomic status
The species was first described in February 1820 by the French explorers Pierre-Médard DiardPierre-Médard Diard
Pierre-Médard Diard was a French naturalist and explorer.Diard studied zoology and anatomy under Georges Cuvier and assisted him in researches on the development of the foetus and on the eggs of quadrupeds. In 1816, he traveled to the East Indies....
and Alfred Duvaucel in their jointly written article "Sur une nouvelle espèce de Sorex — Sorex Glis", which is preceded by an illustration. They observed specimens in Penang
Penang
Penang is a state in Malaysia and the name of its constituent island, located on the northwest coast of Peninsular Malaysia by the Strait of Malacca. It is bordered by Kedah in the north and east, and Perak in the south. Penang is the second smallest Malaysian state in area after Perlis, and the...
and Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
, and considered them a species of Sorex
Sorex
The genus Sorex includes many of the common shrews of Eurasia and North America. Members of this genus, known as long-tailed shrews, are the only members of the tribe Soricini of the subfamily Soricinae...
, and not as a new genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
.
Between 1821 and 1940, several zoologists described the species from other areas. The species still retains many forms of uncertain rank and validity, and is pending a detailed study. Some forms were formerly considered synonyms of Tupaia glis, some were elevated to species level. Synonyms include:
Threats
Common treeshrews are threatened due to deforestationDeforestation
Deforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use....
and ensuing human activities in agriculture, plantation and commercial logging. Moreover, other pressures such as hunting for food and sport can create pressure to the species.
In science
Tupaia glis are being used by researchers as animal models for human diseases because of their close relationship to primates, and their well-developed senses of vision and hearing. Research studies have included hepatitisHepatitis
Hepatitis is a medical condition defined by the inflammation of the liver and characterized by the presence of inflammatory cells in the tissue of the organ. The name is from the Greek hepar , the root being hepat- , meaning liver, and suffix -itis, meaning "inflammation"...
.