Tupaia dorsalisstriped tree shrew

Geographic Range

The striped tree shrew is endemic to Borneo where it is found in Sabah, Sarawak (Malaysia), Brunei, and Kalimantan (Indonesia) except in the south-east. It is native to Brunei Darussalam, Indonesia and Malaysia. However, there has been no recorded species in Sabah in the last twenty years. The striped tree shrew in generally a lowland species. (Han and Stuebing, 2008; Stone, 1995; Wilson, et al., 1998)

Habitat

The striped tree shrew has been recorded form primary and secondary forests but otherwise little else is known of its habitat preferences. From the few specimens found, they prefer lower altitudes that are near the coast, forests or terrestrial biomes which include mangroves, tropical, subtropical moist broadleaf forests. The geographic range they are found in receive an average of 271.94 mm of precipitation per month and an average temperature of 239.1 degrees Celsius.

The terrestrial biomes where they are found include Borneo lowland rain forest, Borneo peat swamp forest, southwest Bornew freshwater swamp forest, Sunda shelf mangroves, and Indo-Malayan and Sundaland heath forests. (Han and Stuebing, 2008; Stone, 1995; Wilson, et al., 1998)

Physical Description

Tupaia dorsalis is also know as the striped tree shrew. Its body size ranges from 140 to 230 mm with a length ranging from 100 to 300 mm. Its tail is bushy with a naked underside while its body is less densely haired. The back of its body is dark and tends to be more speckled olive-brown in appearance, but can be colored in an olive, reddish, brown or black shade. The ventral coloration is typically grey-buff which is lighter than the rest of body (Ankle-Simons, 2007). The striped tree shrew is known for its distinctive long black line down its back that extends from neck to base of tail (Hose, 1893). The hind limbs tend to be slightly longer than the forelimbs and its fingers and toes consist of curved and pointed claws but foot pads are of moderate development. Its ears are immobile and lie flat against its head, and are small and cartilaginous, whereas the eyes are relatively large in size due to the fact that the orbits are completely encircled by bone. The snout has a glandular rhinarium or wet skin similar to that of a dog or cat (Ankle-Simons, 2007). The striped tree shrew has a general appearance similar to that of a squirrel, however the snout is more pointed due to a rostrum-caudally elongated splanchnocranium, and an extended dental jaw. This longer nose contributes to olfactory functions and to help it search for insects. The cranium profile length in males is 2.571 mm and females are 2.542 mm. The dental length in males is 1.352 mm and in females it's 1.355 mm (Endo et al., 2004). The dental formula is I(incisors) = 2/3, C(canines) = 1/1, PM(premolars) = 3/3, and M(molars) = 3/3. This means that there are three premolars above and three premolars on the lower jaw, and there are three molars above, which are well developed bifucated mesostyles and three molars on the lower jaw, which do not have a cingulum. The upper molars have a W pattern (dilambdodont), the second upper incisor is unicuspid and the canines do not have form or function of a true canine. The bone structure includes a well developed clavicle and the metatarsals are not unusually elongated. (Ankle-Simons, 2007; Endo, et al., 2004; Hose, 1893; Lelevier, 2013; Lowther, 2013; Stone, 1995; Ward Lyon, 1913; Wilson, et al., 1998)

  • Sexual Dimorphism
  • sexes alike
  • Average mass
    168.05 g
    5.92 oz
  • Average length
    185.0 mm
    7.28 in

Reproduction

Striped tree shrews are monogamous. However other species in this genus demonstrate polygyny or polyandry. (Ward Lyon, 1913)

Information on T. dorsalis reproduction behavior is lacking, however it is known that the genus Tupaia tend to bear young at all times of year, however January through July tend to provide the greatest productivity. Females reaches sexual maturity at approximately 45 g and male at 16.8 g. Tupaiad gestation period lasts for 45 to 55 days and then give birth to offspring that generally weigh 6 to 8 g. Offspring is typically two but can range from one to four. Weaning lasts for up to 30 days and then sexual maturity is reached at approximately 2 months when the young are forced out of parental territory.

In Tupaidae, females make nests in fallen trees prior to giving birth. The female then gives birth within the nest to provide the young with protection from predators. The young are born naked and their eyes and ears are closed. Shortly after birth, the mother feeds the young milk and then leaves the nest, only returning every 48 hours to feed the young. Each visit is relatively short with young only receiving 5 to 10 milliliters of milk. After four weeks, the young leave the nest with little parental care from mother and no parental care from the father. (Hill, 1965; Lelevier, 2013; Lowther, 2013; Ward Lyon, 1913)

  • Breeding interval
    45 to 55 days.
  • Breeding season
    Year round.
  • Range number of offspring
    1 to 4
  • Average number of offspring
    2
  • Range gestation period
    45 to 55 days
  • Average weaning age
    30 days
  • Average age at sexual or reproductive maturity (female)
    2 months
  • Average age at sexual or reproductive maturity (male)
    2 months

Since striped tree shrews are monogamous, both males and females provide care for the young, with more care provided through lactation. The overall parental care is minimal. (Ward Lyon, 1913)

  • Parental Investment
  • no parental involvement
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
  • post-independence association with parents

Lifespan/Longevity

Not much is known about T. dorsalis specifically, however other tupaia species that are held in captivity don't live very long. Since tree shrews are generally solitary, lifespan in the wild may be relatively short due to the lack of group defense mechanisms. (Ward Lyon, 1913)

Behavior

Tupaia dorsalis is terrestrial and tends to live singly or occasionally in pairs. They fiercely attack intruders of their own species. When in the presence of food, they make a short peculiar whistling sound and make shrill protracted cries when antagonized. Tree shrews in general are very fond of water for drinking and bathing. (Lelevier, 2013; Lowther, 2013; Stone, 1995; Ward Lyon, 1913; Wilson, et al., 1998)

  • Average territory size
    486,839.44 km^2

Home Range

Specific home range data regarding T. dorsalis is lacking. (Ward Lyon, 1913)

Communication and Perception

Not much information is known about the striped tree shrew, however the genus Tupaia is known to scent mark territories with secretions from glands and with urine. Striped tree shrews are diurnal and so visual cues are important in communication. It is suspected that there is possible vocal and tactile communication especially when mating. Vocal communication is used for alarm, attention, contact and defense. (Lelevier, 2013; Lowther, 2013; Ward Lyon, 1913)

Food Habits

Tupaia dorsalis is omnivores. They eat insects, especially flies, crickets, grasshoppers and cockroaches. They also eat fruits, seeds and leaves of plants. They may be seed dispersers due to their fruit eating habits. When eating, they stand up on hind limbs and place the fruit or seed in front of the mouth using the pads of their front limbs.

The digestive tract, similar to other Tupaia species, is made up of a small, simplified stomach, a long, narrow small intestine, and a pouch-like cecum, and smooth large intestine. (Lelevier, 2013; Lowther, 2013; Ward Lyon, 1913; Wilson, et al., 1998)

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • seeds, grains, and nuts
  • fruit

Predation

Predators of tree shrews include snakes, larger carnivorous mammals and raptors. Tree shrews in general react to predation risk by baring teeth and using high pitched vocalizations. (Lelevier, 2013; Lowther, 2013)

Ecosystem Roles

Tupaia dorsalis may be a seed dispenser of fruit bearing trees. (Lelevier, 2013; Lowther, 2013)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

The striped tree shrew is not known for any positive economic importance on humans. (Lowther, 2013)

Economic Importance for Humans: Negative

There are no known negative economic importance on humans. (Lowther, 2013; Ward Lyon, 1913)

  • Negative Impacts
  • injures humans
    • bites or stings

Conservation Status

The striped tree shrew is a rare species and is only known form a handful of specimens (about 20-30). It is found in a few protected areas like Lanjak-Entimau Wildlife sanctuary and Gunung Marut National Park and is listed on CITES Appnedix II. Due to the little information on this species there is an absence of information on habitat preferences. According to IUCN, the striped tree shrew is red listed as data deficient due to the limited sitings and few specimens ever found. It is also listed as a lower risk/ least concern however other sites have that the population trend is decreasing and the extinction status is extant.

Major threats that the striped tree shrew has include loss of habitat due to agricultureal expansion and conversion of land to plantations used for oil palm and cutting down of rainforests due to human encroachment. (Han and Stuebing, 2008; Lelevier, 2013; Stone, 1995; Wilson, et al., 1998)

Other Comments

The genus Tupaia was first proposed by Sir Thomas Stanford Raffles in May, 1821. (Stone, 1995; Ward Lyon, 1913)

Contributors

Melissa Miller (author), University of Wisconsin Stevens Point, Christopher Yahnke (editor), University of Wisconsin-Stevens Point, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

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.

aposematic

having coloration that serves a protective function for the animal, usually used to refer to animals with colors that warn predators of their toxicity. For example: animals with bright red or yellow coloration are often toxic or distasteful.

arboreal

Referring to an animal that lives in trees; tree-climbing.

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

coastal

the nearshore aquatic habitats near a coast, or shoreline.

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

folivore

an animal that mainly eats leaves.

forest

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

frugivore

an animal that mainly eats fruit

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

holarctic

a distribution that more or less circles the Arctic, so occurring in both the Nearctic and Palearctic biogeographic regions.

World Map

Found in northern North America and northern Europe or Asia.

insectivore

An animal that eats mainly insects or spiders.

monogamous

Having one mate at a time.

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.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

sexual

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

solitary

lives alone

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

swamp

a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

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.

year-round breeding

breeding takes place throughout the year

References

Ankle-Simons, F. 2007. Primate Anatomy. United States: Academic Press. Accessed March 02, 2017 at https://books.google.com/books?id=5fttVRAHA4MC&printsec=frontcover&dq=ankle-simons&hl=en&sa=X&ved=0ahUKEwjnrcTbrOLTAhUH7IMKHdVqBf4Q6AEILzAC#v=onepage&q=ankle-simons&f=false.

Endo, H., T. Hikida, L. Chou, K. Fukuta, B. Stafford. 2004. Proportion and Cluster Analyses of the Skull in Various Species of the Tree Shrews. The Journal of Veterinary Medical Science, Volume 66: 1-6. Accessed March 02, 2017 at https://www.ncbi.nlm.nih.gov/pubmed/14960803.

Han, H., R. Stuebing. 2008. "Tupaia dorsalis" (On-line). The IUCN Red List of Threatened Species. Accessed February 22, 2017 at http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T41493A10468506.en..

Hill, J. 1965. On the Placentation of Tupaia. Journal of Zoology, Volume 146/ Issue 3: 278-304. Accessed May 07, 2017 at http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7998.1965.tb05213.x/full.

Hose, C. 1893. A Descriptive Accont of the Mammals of Borneo. London: Harvard University. Accessed March 02, 2017 at books.google.com.

Lelevier, M. 2013. "Animal Diversity Web" (On-line). Tupaia minor. Accessed May 06, 2017 at http://animaldiversity.org/accounts/Tupaia_minor/.

Lowther, T. 2013. "Animal Diversity Web" (On-line). Tupaia belangeri. Accessed May 06, 2017 at http://animaldiversity.org/accounts/Tupaia_belangeri/.

Stone, D. 1995. Eurasion Insectivores and Tree Shrews: Status Survey and Conservation Action Plan. Cambridge, UK: IUCN. Accessed May 05, 2017 at https://books.google.com/books?id=GgtbBAAAQBAJ&pg=PA62&lpg=PA62&dq=tupaia+dorsalis&source=bl&ots=RDxHvP8zUg&sig=5n1OQwKGVHb03gYofogNTIOaPXU&hl=en&sa=X&ved=0ahUKEwi5wP6Rtd7TAhVn7oMKHfqqDyQ4ChDoAQg6MAc#v=onepage&q=tupaia%20dorsalis&f=false.

Ward Lyon, M. 1913. Treeshrews: an account for the mammalian family Tupaiidae. University of Michigan: U.S. Government Print Office. Accessed May 08, 2017 at https://books.google.com/books?hl=en&lr=&id=k1JLAAAAMAAJ&oi=fnd&pg=PA1&dq=tupaia+dorsalis+geographic+range&ots=RUsz0JQXX-&sig=bm5SJvKpUxfNPkixHovK47V81-U#v=onepage&q=tupaia%20dorsalis%20geographic%20range&f=false.

Wilson, D., T. Orrell, M. Nowak. 1998. "Encyclopedia of Life" (On-line). Tupaia dorsalis. Accessed May 07, 2017 at http://www.eol.org/pages/327850/overview.