|
==Taxonomy==
The Java mouse-deer’s common scientific name is ''Tragulus javanicus'', although other classification names for it exist, including ''Tragulus javanica'', ''Cervus javanicus'', and the [[heterotypic synonym]] ''Tragulus fuscatus''.<ref name=meijaard>{{cite journal | last1 = Meijaard, | first1 = I. and| last2 = Groves, | first2 = C. P. (| year = 2004). ''| title = A taxonomic revision of the Tragulus mouse-deer.'' | url = | journal = Zoological Journal of the Linnean Society | volume = 140: 63-102.| issue = | pages = 63–102 }}</ref><ref name=ARKive4>Javan mouse-deer (Tragulus javanicus). (2013). ARKive - Discover the world's most endangered species. Retrieved from http://www.arkive.org/javan-mouse-deer/tragulus-javanicus</ref><ref>Facts about Lesser Mouse Deer (Tragulus javanicus) - Encyclopedia of Life. (n.d.). Encyclopedia of Life - Animals - Plants - Pictures & Information. Retrieved from http://eol.org/pages/328339/names/synonyms</ref><ref name=iucn /> The Java mouse-deer is also known by many common names, including Javan chevrotain, Javan mousdeer, or Java Mousedeer.<ref name=eof5>Facts about Lesser Mouse Deer (Tragulus javanicus) - Encyclopedia of Life. (n.d.). Encyclopedia of Life - Animals - Plants - Pictures & Information. Retrieved from http://eol.org/pages/328339/</ref> The taxonomic status of the Java mouse-deer is questionable, but recent craniometric analyses have begun to shed light on the taxonomic discrepancies. Previously, the Java mouse-deer, ''Tragulus javanicus'', was commonly thought to represent the wider class of large [[chevrotain]]s, but it was found that these, unlike the Java mouse-deer, do not likely reside on [[Java]]. Three species groups of ''Tragulus'' have been identified based on craniometric skull analyses and coat coloration patterns. These three species groups are ''Tragulus javanicus'', ''[[Tragulus napu]]'', and ''[[Tragulus versicolor]]''. Based upon these craniometric analyses, ''Tragulus javanicus'' was then further separated based on the organisms’ known geographic locations: ''[[Tragulus williamsoni]]'' (found in northern Thailand and possibly southern China), ''[[Tragulus kanchil]]'' (found in Borneo, Sumatra, the Thai–Malay Peninsula, islands within the Greater Sunda region, and continental Southeast Asia), and ''Tragulus javanicus'' (found in Java).<ref name=meijaard6>{{cite journal | last1 = Meijaard, | first1 = E., &| last2 = Groves, | first2 = C. P. (| year = 2004). | title = A Taxonomic Revision Of The Tragulus Mouse-deer (Artiodactyla) | url = http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2004.00091.x/abstract | journal = Zoological Journal of the Linnean Society, | volume = 140( | issue = 1),| 63-102.pages Retrieved= from63–102 | http://onlinelibrary.wiley.com/doi/=10.1111/j.1096-3642.2004.00091.x/abstract}}</ref> Thus, because of its uniqueness to the island of Java, the Java mouse-deer is now considered a distinct species, although this fact has not significantly affected its current classification.<ref name=redorbit7>Java Mouse Deer, ''Tragulus javanicus'' - Mammals Reference Library - redOrbit. (n.d.). redOrbit - Science, Space, Technology, Health News and Information. Retrieved from http://www.redorbit.com/education/reference_library/science_1/mammalia/1112721404/java-mouse-deer-tragulus-javanicus/</ref>
==Appearance and biology==
Mouse-deer possess a triangular-shaped head, arched back, and round body with elevated rear quarters. The thin, short legs which support the mouse-deer are about the diameter of a pencil. Although Java mouse-deer do not possess antlers or horns like regular deer, male Java mouse-deer have elongated, tusk-like upper canines which protrude downward from the upper jaw along the sides of their mouth. Males use these “tusks” to defend themselves and their mates against rivals.<ref name=superhero8>Nowak, R., J. Paradiso. 1983. Walker's Mammals of the World. Chicago: Johns Hopkins University Press.</ref> Females can be distinguished from males because they lack these prominent canines, and they are slightly smaller than the males.<ref name=eof5/> The average size of a Java mouse-deer ranges from {{Convert|1|-|2|kg}}, with females falling on the smaller end of this spectrum. Java mouse-deer can furthermore be distinguished by their lack of upper incisors. The coat coloration of the Java mouse-deer is reddish-brown with a white underside. Pale white spots or vertical markings are also present on the animal’s neck.<ref name=eof5/>
The height of the Java mouse-deer is {{Convert|30|cm}} on average. With average lengths of {{Convert|45|cm|abbr = on}} and an average tail length of {{Convert|5|cm|abbr = on}}, the Java mouse-deer is the smallest extant [[artiodactyl]] (even-toed hoofed mammal).<ref name=eof5/> Java mouse-deer are [[endothermic]] and [[homoeothermic]], with an average basal metabolic rate of 4.883 W.<ref name=eof5/> Tragulus javanicus also possess the smallest [[erythrocytes]] of the mammalian species, and their erythrocytes are unique in that 12.8% of their erythrocytes have pits in them.<ref name=erythrocytes9>{{cite journal | last1 = Fukuta, | first1 = K., | last2 = Kudo, | first2 = H., &| last3 = Jalaludin, | first3 = S. (| year = 1996). | title = Unique pits on the erythrocytes of the lesser mouse-deer, Tragulus javanicus. | journal = Journal of Anatomy, | volume = 189( | issue = 1),| 211-213.pages Retrieved= from211–213 | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1167845/=1167845 | pmid=8771414}}</ref> Pitted erythrocytes are unique and have never been seen before physiologically or pathologically. Java mouse-deer are also considered the most primitive [[ruminants]], thus they provide the living link between non-ruminants and ruminant species.<ref name=animalrecs10>Carwardine, M., & London, E. (2007). Animal records. New York: Sterling</ref>
==Ecology==
===Social behavior===
Groups of Java mouse-deer are commonly referred to as “herds,” while females are termed “does,” “hinds,” or “cows.” Males are referred to as either “bucks,” “stags,” or “bulls,” and their young are commonly called “fawns,” or “asses”.<ref name=superhero8/>
It was previously believed that Java mouse-deer were [[nocturnal]], but more recent studies have shown that they are neither truly nocturnal nor [[Diurnality|diurnal]], but instead [[crepuscular]], meaning they prefer to be active during the dim light of dawn and dusk.<ref name=superhero8/> This behavior has been observed in both wild and captive Java mouse-deer.<ref name=matsubayashi13>{{cite journal | last1 = Matsubayashi, | first1 = H., | last2 = Bosi, | first2 = E., &| last3 = Kohshima, | first3 = S. (| year = 2003). | title = Activity And Habitat Use Of Lesser Mouse-Deer (Tragulus Javanicus). | url = | journal = Journal of Mammalogy, | volume = 84( | issue = 1),| 234-242.pages = 234–242 }}</ref> Although Java mouse-deer form [[monogamous]] family groups, they are usually shy, solitary animals. They are also usually silent; the only noise they make is a shrill cry when they are frightened.
Male Java mouse-deer are territorial, marking their territory and their mates with secretions from an intermandibular scent gland under their chin.<ref name=superhero8/> This territorial marking usually includes urinating or defecating to mark their area. To protect themselves and their mates or to defend their territory, mouse-deer slash rivals with their sharp, protruding canine “tusks.” It has also been observed that, when threatened, the Java mouse-deer will beat its hooves quickly against the ground, reaching speeds of up to 7 beats per second, creating a “drum roll” sound.<ref name=prothero14>Prothero, D. R., & Foss, S. E. (2007). The evolution of artiodactyls. Baltimore: Johns Hopkins University Press</ref>
==Diseases==
Although research into the diseases and parasites which affect the Java mouse-deer are still nascent, bovine viral diarrhea virus ([[BVDV]] 1), a [[pestivirus]] of the family [[flaviviridae]] has been detected in Java mouse-deer. Mouse-deer acquire this virus through fetal infection during early pregnancy. Once acquired, individuals with BVDV can gain lifelong [[immune tolerance]].<ref>{{cite journal | last1 = Uttenthal, | first1 = A., | last2 = Hoyer, | first2 = M. J., | last3 = Grøndahl, | first3 = C., | last4 = Houe, | first4 = H., | last5 = Maanen, C.| v.,first5 = | last6 = Rasmussen, | first6 = T. B., | display-authors = 6 | last7 = et al. (| year = 2006). | title = Vertical Transmission Of Bovine Viral Diarrhoea Virus (BVDV) In Mousedeer (Tragulus Javanicus) And Spread To Domestic Cattle. | url = | journal = Archives of Virology, | volume = 151( | issue = 12),| 2377-2387.pages = 2377–2387 }}</ref>
==Conservation status==
|
