Tapir
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Tapirus bairdii |
Tapirs (IPA:ˈteɪpər, pronounced as in "taper", or IPA:təˈpɪər, pronounced as in "tap-ear") are large browsing mammals, roughly pig-like in shape, with short, prehensile snouts. They inhabit jungle and forest regions of South America, Central America, and Southeast Asia. All four species of tapir are classified as endangered or vulnerable. Their closest relatives are the other odd-toed ungulates, horses and rhinoceroses.
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[edit] Species
There are four tapir species:
- Baird's Tapir, Tapirus bairdii
- Malayan Tapir, Tapirus indicus
- Mountain Tapir, Tapirus pinchaque
- Brazilian Tapir (also called Lowland Tapir), Tapirus terrestris
[edit] Hybrids
Hybrid tapirs from the Baird's Tapir and the Brazilian Tapir were bred at the San Francisco Zoo around 1969 and produced a second generation around 1970.[1]
[edit] General appearance
Size varies between species, but most tapirs are about 2 meters (7 ft) long, stand about a meter (3 ft) high at the shoulder, and weigh between 150 and 300 kg (330 to 700 lb). Coats are short and range in color from reddish-brown to grey to nearly black, with the notable exceptions of the Malayan Tapir, which has a white saddle-shaped marking on its back, and the Mountain Tapir, which has longer, wooly fur. All tapirs have oval, white-tipped ears, rounded, protruding rear ends with stubby tails, and splayed, hoofed toes, with four toes on the front feet and three on the hind feet, which help them walk on muddy and soft ground. Baby tapirs of all types have striped-and-spotted coats for camouflage, and while they appear at first glance to be alike, there are some differences among the patterns of different species. Females have a single pair of mammary glands.[2] The penis of the male tapir is very long when erect. The tapir has one of the longest penis to body size ratios of any animal. The specimen of tapir believed to have the longest penis ever observed is currently on display at the Koenigsberg Zoo.
[edit] Physiology
The proboscis of the tapir is a highly flexible structure, able to move in all directions, allowing the animals to grab foliage that would otherwise be out of reach. Tapirs often exhibit the flehmen response, a posture in which they raise their snouts and show their teeth, in order to detect scents. This response is frequently exhibited by bulls sniffing for signs of other males or females in oestrus in the area. Proboscis length varies among species; Malayan Tapirs have the longest snouts and Brazilian Tapirs have the shortest.[3] The evolution of tapir probosces, made up almost entirely of soft tissues rather than bony internal structures, gives the Tapiridae skull a unique form in comparison to other perissodactyls, with a larger sagittal crest, orbits positioned more rostrally, a posteriorly telescoped cranium, and a more elongated and retracted nasoincisive incisure.[4] [5]
Tapirs have brachyodont, or low-crowned, teeth that lack cement. Their dental formula is I 3/3, C 1/1, P 4/3-4, M 3/3, totaling 42 to 44 teeth; this dentition is closer to that of equids, who may differ by one less canine, than their other perissodactyl relatives, rhinoceroses.[6] [7] Their incisors are chisel-shaped, with the third large, conical upper incisor separated by a short gap from the considerably smaller canine. A much longer gap is found between the canines and premolars, the first of which may be absent.[8] Tapirs are lophodonts, and their cheek teeth have distinct lophs (ridges) between protocones, paracones, metacones and hypocones.[9] [10]
Tapirs have brown eyes, often with a bluish cast to them which has been identified as corneal cloudiness, a condition most commonly found in Malayan Tapirs. The exact etiology is unknown, but the cloudiness may be caused by excessive exposure to light or by trauma.[11] [12] However, the tapir's sensitive ears and strong sense of smell help to compensate for deficiencies in vision.
[edit] Natural history
The tapir family is old by mammalian standards. The earliest fossil tapir dates to the early Oligocene, and Eocene rocks from as early as 55 million years ago contain a wide range of tapir-like animals, and they have changed little since.[1] These ungulates could be found world-wide. Perissodactyls, including tapiroids, became the predominant large terrestrial browsers through the Oligocene, and many members of the group survived until the late Pleistocene. It is believed that Asian and American tapirs diverged around 20 to 30 million years ago, and that tapir varieties moved from North America to Central and South America around 3 million years ago.[13]
[edit] Lifecycle
Young tapirs reach sexual maturity between three and five years of age, with females maturing earlier and coming into oestrus every two or three months.[14] [15] Under good conditions, a healthy female tapir can reproduce every two years; a single youngster is born after a gestation of about 13 months. The natural lifespan of a tapir is approximately 25 to 30 years, both in the wild and in zoos. Little is known for sure about tapirs’ mating patterns in the wild: there is some evidence that mature tapirs mate with the same partner for life, but pairs spend little or no time together aside from sexual activity.[16] Apart from mothers and their young offspring, tapirs lead almost exclusively solitary lives.
[edit] Behavior
Although they frequently live in dryland forests, tapirs with access to lakes or rivers spend a good deal of time in and under the water, feeding on soft vegetation, taking refuge from predators, and cooling off during hot periods. Tapirs near a water source will swim, sink to the bottom and walk along the riverbed to feed, and have been known to submerge themselves under water to allow small fish to pick parasites off their bulky bodies.[17] Along with fresh water lounging, tapirs often wallow in mud pits, which also helps to keep them cool and free of insects.
In the wild, the tapir’s diet consists of fruit, berries, and leaves, particularly young, tender growth. Tapirs will spend many of their waking hours foraging along well-worn trails, snouts to the ground in search of food. Baird’s Tapirs have been observed to eat around 40 kilograms (85 pounds) of vegetation in one day.[18]
Tapirs are largely nocturnal and crepuscular, although the smaller Mountain Tapir of the Andes is generally more active during the day than its congeners. They have monocular vision.
[edit] Habitat, predation, and vulnerability
Adult tapirs are large enough that they have few natural predators, and the thick skin on the backs of their necks helps to protect them from threats such as jaguars, crocodiles, anacondas, and tigers. The creatures are also able to run fairly quickly, considering their size and cumbersome appearance, finding shelter in the thick undergrowth of the forest or in water. However, tapirs have no reliable defense against humans, by far the greatest threat to their survival. Hunting for meat and hides has substantially reduced their numbers and, more recently, massive habitat loss has resulted in the conservation watch-listing of all four species: both the Brazilian Tapir and the Malayan Tapir are classified as vulnerable; and the Baird’s Tapir and the Mountain Tapir are endangered. Tapirs tend to prefer old growth forests and the food sources that can be found in them, making the preservation of primary woodlands a top priority for tapir conservationists.
[edit] Genetics
The four species of tapir have the following chromosomal numbers:
| Malayan tapir, T. indicus | 2n = 52 |
|---|---|
| Mountain tapir, T. pinchaque | 2n = 76 |
| Baird's tapir, T. bairdii | 2n = 80 |
| Brazilian tapir, T. terrestris | 2n = 80 |
The Malayan tapir, the species most isolated geographically from the rest of the genus, has a significantly smaller number of chromosomes and has been found to share fewer homologies with the three types of American tapirs. A number of conserved autosomes (13 between karyotypes of the Baird’s Tapir and Brazilian Tapir, and 15 between the Baird’s and Mountain Tapir) have also been found in the American species that are not found in the Asian animal. However, geographic proximity is not an absolute predictor of genetic similarity; for instance, G-banded preparations have revealed that Malayan, Baird’s and Brazilian Tapirs have identical X chromosomes, while Mountain Tapirs are separated by a heterochromatic addition/deletion.[19]
Lack of genetic diversity in tapir populations has become a major source of concern for conservationists. Habitat loss has isolated already small populations of wild tapirs, putting each group in greater danger of dying out completely. Even in zoos, genetic diversity is limited; all captive mountain tapirs, for example, are descended from only two founder individuals.[20]
[edit] Attacks on humans
Tapirs are generally shy, but when they are scared they can defend themselves with their very powerful jaws. In 1998, a zookeeper in Oklahoma City was mauled and had an arm severed by a tapir bite, after she attempted to feed the attacking tapir's young.[21] In 2006, a 46-year-old man (who was the Environmental Minister at turn) who was lost in the Costa Rican jungle was found by a search party with a "nasty bite" from a wild tapir.[22] However, such examples are rare; for the most part, tapirs are likely to avoid confrontation in favor of running from predators, hiding, or, if possible, submerging themselves in nearby water until a threat is gone.[23]
[edit] Cultural references
In Chinese, Korean and Japanese, the tapir is named after a beast from Chinese mythology. A feature of this mythical creature is a snout like that of an elephant. It is said to eat people's dreams. In Chinese, the name of this beast, subsequently the name of the tapir, is mò in Mandarin and mek in Cantonese (貘). The Korean equivalent is maek (Hangul: 맥, Hanja: 貊), while it is called baku (バク) in Japanese. The Chinese file hosting service Mofile has been referred to as the tapir by Chinese-speaking users.
Tapirs appear in the initial section of the movie 2001: A Space Odyssey. The first section of the movie, entitled "The Dawn of Man," is set in the Pleistocene era, and shows Brazilian tapirs grazing in the background. This is inaccurate due to the fact that the scene was set in a desert environment. Tapirs have never been recorded living in any sort of desert, either through live sightings, secondary evidence, or fossil record. More recently, the opening scene of another feature film, Apocalypto, involved a tapir hunt.
In the video game and anime series Pokémon, the Pokémon Drowzee resembles a tapir and is said to eat dreams.
In the video game and anime series Digimon, the Digimon Tapirmon is modeled after a tapir.
[edit] Notes
- ^ Pictures of T. bairdii x T. terrestris cross taken by Sheryl Todd, The Tapir Gallery, web site of the Tapir Preservation Fund
- ^ Gorog, A. 2001. Tapirus terrestris, Animal Diversity Web. Accessed June 19, 2006
- ^ Witmer, Lawrence, Scott D. Sampson, and Nikos Solounias. “The proboscis of tapirs (Mammalia: Perissodactyla): a case study in novel narial anatomy”. Journal of Zoology, 1999, The Zoological Society of London; page 251
- ^ Witmer, page 249
- ^ Colbert, Dr. Matthew, 2002, "Tapirus terrestris" (On-line), Digital Morphology. Accessed June 20, 2006
- ^ Ballenger, L. and P. Myers. 2001. "Tapiridae" (On-line), Animal Diversity Web. Accessed June 20, 2006
- ^ Huffman, Brent. Order Perissodactyla at Ultimate Ungulate
- ^ "PERISSODACTYLA." LoveToKnow 1911 Online Encyclopedia
- ^ Myers, P., R. Espinosa, C. S. Parr, T. Jones, G. S. Hammond, and T. A. Dewey. 2006. The Diversity of Cheek Teeth. The Animal Diversity Web (online). Accessed June 20, 2006
- ^ Myers, P., R. Espinosa, C. S. Parr, T. Jones, G. S. Hammond, and T. A. Dewey. 2006. The Basic Structure of Cheek Teeth. The Animal Diversity Web (online). Accessed June 20, 2006
- ^ Tapirs Described, the Tapir Gallery
- ^ Janssen, Donald L., DVM, Dipl ACZM, Bruce A. Rideout, DVM, PhD, Dipl ACVP, Mark E. Edwards, PhD. "Medical Management of Captive Tapirs (Tapirus sp.)." 1996 American Association of Zoo Veterinarians Proceedings. Nov 1996. Puerto Vallarta, Mexico. Pp. 1-11
- ^ Ashley, M.V., Norman, J.E. and Stross, L.: "Phylogenetic analysis of the perissodactylan family tapiridae using mitochondrial cytochrome c oxidase (COII) sequences." Mammal Evolution. 3:315-326, 1996.
- ^ Woodland Park Zoo Animal Fact Sheet: Malayan Tapir (Tapirus indicus)
- ^ "Wildfacts" sheet on the Brazilian Tapir (Tapirus terrestris),'' BBC Science and Nature
- ^ Morris, Dale. “Face to face with big nose.” BBC Wildlife, March 2005, page 37.
- ^ Morris, page 36.
- ^ TPF News, Tapir Preservation Fund, Vol. 4, No. 7, July 2001. See section on study by Charles Foerster.
- ^ Houck, M.L., S.C. Kingswood, A.T. Kumamoto. “Comparative cytogenetics of tapirs, genus Tapirus (Perissodactyla, Tapiridae). Cytogenetics and Cell Genetics 2000; 89: 110-115 (DOI: 10.1159/000015587)
- ^ Mountain Tapir Conservation at the Cheyenne Mountain Zoo
- ^ "Woman's arm bitten off in zoo attack", Associated Press report by Jay Hughes, 20 Nov 1998
- ^ "Lost Costa Rica minister found with tapir bite", Reuters, 23 Apr 2006 01:11:51 GMT
- ^ Goudot, Justin. "Nouvelles observations sur le Tapir Pinchaque (Recent Observations on the Tapir Pinchaque)," Comptes Rendus, Paris 1843, vol. xvi, pages 331-334. Available online with English translation by Tracy Metz. Report contains accounts of wild Mountain Tapirs shying away from human contact at salt deposits after being hunted, and hiding.
[edit] External links
- IUCN/SSC Tapir Specialist Group
- The Tapir Gallery at The Tapir Preservation Fund website
- Andes-Amazon Botany Program Tapir Project
- In the Name of the Tapir: Confusions and Conclusions a paper by Stefan Seitz about misidentification of tapirs by zoo visitors, including a zoological description of tapirs in rhyme
