Tapir Fossil range: Early Eocene–Recent |
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![]() Brazilian Tapir
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Scientific classification | ||||||||||||
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Species | ||||||||||||
Tapirus bairdii |
Tapirs (pronounced /ˈteɪpɚ/, as in "taper", or /təˈpɪər/, as "ta-pier") 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, including horses and rhinoceroses.
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There are four tapir species:
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]
Size varies between types, 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, woolly fur. All tapirs have oval, white-tipped ears, rounded, protruding rumps 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. Females have a single pair of mammary glands.[2]
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
3.1.4.3 |
3.1.3-4.3 |
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.
Young tapirs reach sexual maturity between three and five years of age, with females maturing earlier.[13] 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.[14] Apart from mothers and their young offspring, tapirs lead almost exclusively solitary lives.
Although they frequently live in dryland forests, tapirs with access to 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.[15] 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.[16]
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.
Copulation may occur in or out of water, and in captivity, mating pairs will often copulate multiple times during oestrus.[17][18]
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. 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.
The first tapirids, such as Heptodon, appeared in the early Eocene.[19] They appeared very similar to modern forms, but were about half the size, and lack the proboscis. The first true tapirs, appeared in the Oligocene, and by the Miocene, such genera as Miotapirus were almost indistinguishable to the extant species. 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.[20] For much of their history, tapirs were spread across the northern hemisphere, where they became extinct as recently as 10,000 years ago.[21]
It is also believed by some scientists that the tapir may have evolved from the Hyracotherium (primitive horse).[22]
The four species of tapir have the following chromosomal numbers:
Malayan tapir, T. indicus | 2n = 52 |
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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.[23]
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.[24]
There are a number of conservation projects around the world. The Tapir Specialist Group, a unit of the IUCN Species Survival Commission, strives to conserve biological diversity by stimulating, developing, and executing practical programs to study, save, restore, and manage the four species of tapir and their remaining habitats in Central and South America and Southeast Asia.[25]
The Baird's Tapir Project of Costa Rica is the longest ongoing tapir project in the world, having started in 1994. It is currently led by Kendra Bauer and involves placing radio collars on tapirs in Costa Rica's Corcovado National Park to study their social systems and habitat preferences.[26]
27 April 2008, is World Tapir Day. The day has been established to raise awareness about the four species of tapir that inhabit Central and South America and South-East Asia.[27]
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.[28] In 2006, a 46-year-old man (who was the Environmental Minister at the time) who was lost in the Corcovado National Park at Costa Rica was found by a search party with a "nasty bite" from a wild tapir.[29] 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.[30]
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. In Japanese folklore, tapirs can 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.
The opening scene of the 2006 action-adventure film Apocalypto showcased the hunt of a Baird's tapir by Maya villagers.[31]
In the film, 2001: A Space Odyssey, in a prehistoric scene, a tapir is shown being killed by an ape. The tapir is assumed to represent an unknown primitive mammal in the film as there is no record of tapirs ever existing in Africa [32].
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