# Tapirs

Tapirs

Central American tapir ( Tapirus bairdii )

Systematics
 Class : Mammals (mammalia) Subclass : Higher mammals (Eutheria) Superordinate : Laurasiatheria Order : Unpaired ungulate (Perissodactyla) Family : Tapirs Genre : Tapirs
Scientific name of the  family
Tapiridae
JE Gray , 1821
Scientific name of the  genus
Tapirus
Brisson , 1762

The tapirs ( Tapirus ) are the only recent genus of the mammalian family of the same name in German (Tapiridae) from the order of the odd ungulate (Perissodactyla). The genus was once very diverse and today still includes five living species. These are animals with a strong physique and a characteristic short trunk that live mainly in closed tropical forests and feed on mostly soft vegetable foods. They are a very old genus and have been recorded as early as the Middle Miocene 14 million years ago. Today, the tapirs are with the lowland and the mountain and the Kabomani tapir in South America , with the Central American Tapir in Central America and the Malayan tapir in Southeast Asia spread.

## anatomy

### Appearance

Tapirs are distantly pig-like animals; however, their closest relatives are horses and rhinos . The animals reach a head-trunk length of over 100 to 250 cm, the tail is a short stub 5 to 13 cm in length, the shoulder height is 73 to 120 cm. Adults reach a weight of 110 to 320 kg - the largest recent representative is the black-backed tapir ( Tapirus indicus ). Fossil appeared with Tapirus augustus , also known as Megatapirus , an even larger species that exceeded the black-backed tapir in all measurement features by 25%. Very small extinct species like Tapirus polkensis also reached a weight of only 110 to 140 kg.

The plump, clumsy body of these animals is pointed at the front and rounded at the back, which makes it easier for them to move forward in dense forests. The fur of the American species is brownish-gray in color, while the Southeast Asian saddleback tapir is characterized by a conspicuous, black and white coloration. The head looks relatively small compared to the body. The eyes are small, the ears oval and erect and very mobile. In some species the tips are colored white. The trunk formed from the upper lip and nose is characteristic . The legs are comparatively short and slender, as with all odd-toed ungulates, the main axis runs through the third toe, which is also the largest. Four toes are formed on each of the front legs, with the three forward-pointing ones being the most developed, the outer one being reduced in length, the hind feet have three toes.

### Skull and dentition features

Skull of a Central American tapir
Typical molar of a tapir with two transverse melting strips

The skull of the tapirs is usually elongated and flat. Characteristic of the South American species is the crest on the middle of the roof of the skull, which is formed by the inner ends of the parietal bones . The Central American tapir ( Tapirus bairdii ) and the black-backed tapir do not have any formed crests. They have a bony elevation ( parasagittal back ) on each side of the parietal bones, approximately at the level of the brain chamber , between which a narrow flat plane is formed. The occiput is rather short and rectangular. The nasal bone has only a weak expression and is quite short. Typically for tapirs, it lies far behind and above the middle jawbone and is not connected to it, so that a very large interior space is created. The entire front face area is greatly reduced. This was necessary to make room for the elaborate muscles of the trunk.

The tapir's teeth are hardly reduced and are similar to those of the early mammals. Adult animals have the following tooth formula : So there are a total of 42 to 44 teeth. The incisors are small and conical, except for the upper third ( I 3), which is significantly enlarged. The canines are also conical, the lower one is very large, while the upper one is significantly smaller. Thus, the lower canine and upper external incisor form an effective bite tool. The front teeth are separated from the molars by a diastema . The premolars are similar in shape to the molars , so they are clearly molarized. As with all odd-toed ungulates, the molars are characterized by two transverse enamel ridges on the chewing surface ( bilophodont ). Furthermore, the teeth are low-crowned and have relatively little dental cement , so they are equipped for soft plant food. In these characteristics, the fossil tapir species do not differ from one another, although the premolars are partly molarized to different degrees. ${\ displaystyle {\ frac {3.1.4.3} {3.1.3 (4) .3}}}$

### Trunk

Pleading saddlecloth tapir with a clearly visible trunk

The nose and upper lip have grown together to form a small proboscis that the animals use to track down and take their food from the leaves. The black-backed tapir has the longest trunk and the flatland tapir ( Tapirus terrestris ) the shortest . Since the fossil tapirs have a similar skull structure, this trunk formation is to be regarded as typical for the genus. As with the elephants , the trunk is a tube made entirely of muscles with two continuous nostrils, but it is significantly shorter than that of the trunk animals. It does not have any bony substructure, the attachment to the facial skull has been evolutively restructured , as already mentioned above, by reducing the facial bones and differs significantly from other unpaired ungulates. The high mobility of the trunk is guaranteed by three main muscle groups, which run lengthways and crossways or helically. Above all, several large facial muscles, such as the levator labii superioris and the levator nasolabialis muscles, underwent significant changes to enable the trunk to move freely. In contrast to the elephants, there was no further alteration of the skull or the teeth. The short trunk of the tapirs does not allow the elephant's trunk to be used in a variety of ways, just as the size of the usable objects is limited by the tapirs. But as tapirs, such as pushing the elephants use their trunks to foraging and plants into the mouth, and it also, snorkeling and similar use to smell, he can derogation from the trunk-like formations in other mammals such as pigs , elephant-shrews or Dikdiks than functional real proboscis ( proboscis ).

### Internal organs

Like all odd ungulates , tapirs are rectum fermenters , as most of the digestion, with the participation of numerous microorganisms , takes place in the back of the intestine . The stomach has a single cavity and is relatively small, the entire intestinal tract is up to 11 m in length, but with an appendix that is relatively small for odd-toed ungulates . The kidneys contain around three million kidney corpuscles and weigh up to 390 g, which is only a maximum of 0.5% of the body mass with two kidneys.

## Distribution area and habitat

Tapirs today have a two-part distribution area: four species live in Central and South America , where they are distributed from southern Mexico to southern Brazil and northern Argentina . The fifth species, the black-backed tapir, lives in Southeast Asia , from Myanmar to the Malay Peninsula and on Sumatra . This dichotomy of the distribution area is a relic of the originally much wider distribution. In the Miocene and Pliocene , tapirs were found in the entire Eurasian region with the exception of the Indian subcontinent and also in large parts of North America ; South America was only reached in the middle Pliocene with the closure of the Isthmus of Panama and the subsequent Great American Faun Exchange . As a result of climate changes to cooler temperatures and stronger seasonalization of the year - combined with the spread of open landscapes in the Miocene and Pliocene to the Pleistocene - the tapirs disappeared again from Europe, North Asia and North America.

The habitat of the tapirs are forests, primarily tropical rainforests , but also mountain cloud forests. They depend on the proximity of water and occur from sea level to altitudes of 4500 m. Since tapirs are a conservative genus with only minor physical changes over time, this is also assumed for the fossil species.

## Way of life

### Territorial behavior

The black-backed tapir is the only species that lives in Southeast Asia

Tapirs are territorial loners; when conspecifics meet each other, they often behave very aggressively. Only during the mating season do males and females come together for a short time. The territories are between 1 and 8 km² in size, with females sometimes having larger territories, and usually consist of several sleeping, feeding and wallowing places. The boundaries and well-traveled paths are marked with feces and urine . The animals are nocturnal, during the day they withdraw into the thick undergrowth. At night they go looking for food. They move forward, holding their trunk on the ground. They often stay near bodies of water . They can swim and dive well, and mud baths are also common. In general, tapirs are very shy and cautious, in case of threat they flee into the water or take flight; if necessary, defend themselves with bites. Hearing and smell are well developed.

### Diet

Tapirs are herbivores that eat mostly soft foods. In addition to leaves, they also consume aquatic plants , buds , twigs and fruits . With their long, muscular and flexible tongues, they can also reach the leaves of thorny plants. Several hundred plant species are known that serve as the food source of the individual tapir species. Through their excretions, the animals also spread the seeds of plants on their migrations and thus represent an important ecological factor in the tropical forests. Some tapir species regularly use mineral and salt licks to neutralize the poisons that are partially absorbed through plant food and to maintain the material cycle . The tapirs' high dependence on water is also known, as they adapt their drinking behavior to local conditions and thus consume significantly more water in dry regions.

### Reproduction

Young lowland tapir with typical coat patterns

The gestation period lasts 13 to 14 months (around 390 to 410 days). As a rule, a single young animal is born, rarely two. Newborns look the same in all types of tapir: They are dark brown and have light brown to white vertical stripes that can be broken up into spots and lines. The boy spends its first week of life in a sheltered camp, after which it begins to follow its mother, who protects it from possible dangers and defends it if necessary.

After a few weeks, the coat pattern of the young begins to gradually disappear, which is completed in about half a year. From the first year of life, the young tapir looks like an adult animal. At about the same time, he is weaned and driven away by his mother. Sexual maturity occurs at around three to four years of age. In the wild, tapirs live to be around 30 years old; the highest known age of a captive tapir was 35 years.

### Enemies and enemy behavior

Natural enemies include large cats such as puma , jaguars and tigers , but also bears and crocodiles . Tapirs often flee, but can also defend themselves well with their large canine teeth. The greatest threat to the tapirs, however, is man . Attacks by the tapirs on humans only take place extremely rarely and take place when harassed.

## Systematics

### External system

The genus Tapirus represents a branch within the family of the Tapiridae , and is closely related to the extinct genera Tapiravus and Tapiriscus related. These occurred around the same time, but were on average mostly smaller than the tapirs; However, they have hardly been explored due to the few fossil finds. The closest living relatives of the Tapiridae family are the rhinos . Both lines of development separated in the middle Eocene around 47 million years ago. The Tapiridae are regarded as part of the superfamily Tapiroidea . Together with the rhinoceros superfamily Rhinocerotoidea, they form the group of Ceratomorpha , which, within the order of the odd- toed ungulates ( Perissodactyla ), faces the Hippomorpha with the horses . The horses had split off from the tapirs line 56 million years ago. In general, the odd ungulates are assigned to the parent group of Laurasiatheria .

### Internal system

Internal system of the genus Tapirus (only recent representatives) according to Price et al. 2009 and Cozzuol et al. 2013
Tapirus

Today there are five species of tapir: the lowland tapir ( Tapirus terrestris ), the mountain tapir ( Tapirus pinchaque ) and the kabomani tapir ( Tapirus kabomani ) in South America, as well as the Central American tapir ( Tapirus bairdii ) in Central America and the black-backed tapir ( Tapirus indicus ) in Southeast Asia the earth. According to molecular genetic studies, the Asian tapir separated from the line of tapirs first 21 to 23 million years ago, the Central American tapir followed shortly after 19 to 20 million years ago. The separation of the line of the South American tapir species from the Central American tapir took place around 3.1 to 3.5 million years ago. Possibly this happened on the South American continent, which the ancestral form of these three today's tapir species took after the closure of the Isthmus of Panama and the creation of a land bridge. The differentiation into the three today's tapir representatives of South America - the flatland and mountain tapir and the Kabomani tapir - did not take place until the Middle Pleistocene , 288,000 to 652,000 years ago. Together with the fossil tapir representatives of South America, they form a closer relational unit and stand out from the tapir species of North and Central America. The relationship between the Eurasian tapirs has not been sufficiently clarified.

In addition to the five recent ones, numerous fossil tapir species have been described, of which the following are valid today:

• American tapir species
Internal classification of the American tapirs (including the recent saddleback tapir) according to Cozzuol et al. 2013
Tapirus

• Eurasian tapir species

Furthermore, four of the five today's tapir species were assigned their own sub-genus, and there are also two fossil sub-genuses. The breakdown into the individual sub-genres is, however, not without controversy, since, according to some experts, it complicates the taxonomy of the genus:

• Subgenera
• Acrocodia ( saddleback tapir and Eurasian tapir species)
• Helicotapirus ( T. haysii , T. lundeliusi , T. veroensis )
• Megatapirus ( T. augustus )
• Pinchacus (mountain tapir )
• Tapirella (Central American tapir)
• Tapirus (lowland tapir)

## Tribal history

### Origins

Fossil representative of the tapir-like species: Hyrachyus minimus from the Middle Eocene (find from the Messel pit )

In tribal history, the tapirs are a very old family compared to other mammals. An early ancestor of tapir-like animals could be found in the genus Hyrachyus from the Early and Middle Eocene . In the Messel Pit in particular , a complete skeleton from around 44 million years ago has come down to us, but fossil remains have been found in both Europe and North America. Due to the very original design of the skeletal structure, the genus is placed by some experts on the basis of the superfamily of the Tapiroidea on the one hand, and the superfamily of the Rhinocerotoidea on the other. On the other hand, some groups such as the Deperetellidae with forms such as Deperetella , Teleolophus and Irenolophus or the Helaletidae , to which Heptodon , Helaletes and Colodon are assigned, are to be rated as basic members of the Tapiroidea. Some experts see the Colodon from the Upper Eocene as a representative of the tapir family, also Thuliadanta , described for the first time in 2005 based on finds from northern Canada , it could have already belonged to it. The oldest fossils, which are clearly included in the tapir family ( Tapiridae ), come from the early Oligocene in Europe and are over 30 million years old. They are usually assigned to the genus Protapirus and appeared in connection with the Grande Coupure event, an extinction phase caused by a deterioration in the climate, which caused a large exchange of fauna. Protapirus was characterized, like other early Eurasian forms, such as Paratapirus and Eotapirus , by hardly molarized premolars and much slimmer limbs and possibly already had a short proboscis. In North America, undoubted representatives of the Tapiridae family can be detected for the first time in the late Oligocene and are also assigned to Protapirus . Here, among other things, developed with Miotapirus and Nexuotapirus own early Tapirlinien.

### Miocene

Upper jaw of Tapirus priscus

The genus Tapirus first appeared in Europe in the Middle Miocene 14 million years ago. The direct ancestor is unknown, Protapirus may represent it . However, no finds from the early Miocene in western Eurasia are known, so that the genus apparently immigrated from Asia. The lack of fossils of this group of animals is known as the tapir vacuum and includes a climatically favorable phase 18 to 14 million years ago. Earlier finds of Tapirus reported as early as the Oligocene are extremely questionable. Several forms developed in Europe, the oldest is T. telleri , other important ones include T. antiquus and T. priscus . In the late Miocene, seven million years ago, the medium-sized form T. arvernensis was added. This tapir species is a regular, albeit numerically rare, representative in European fauna communities, a complete skeleton has been handed down from Camp dels Ninots in Spain , but which dates from the Pliocene . In the late Miocene and in the transition to the Pliocene, all small tapir species died out in western Eurasia and were replaced by medium to large forms. Before that, some species had already disappeared during the Central Valesium Crisis , a cold snap that led to a significant seasonalization of the climate.

In East and Southeast Asia, the genus Tapirus is only detectable in the Upper Miocene 9.5 million years ago and is largely present in the Pliocene and Pleistocene . The oldest representative is called T. yunnanensis . However, the origin of the genus is assumed to be in this region, since the genus Plesiotapirus appeared here during the tapir vacuum , which is sometimes only viewed as a side branch. In North America, tapirus appears similar to Europe in the Middle Miocene 11 million years ago, also after the tapir vacuum . T. johnsoni is one of the earliest species . Representatives of this form of tapir are fossilized from the Ash Hollow Formation in the Great Plains of Nebraska , they were killed in a catastrophic volcanic eruption . The main distribution center was the southern part of the continent, from California to Florida . Important species are also T. webbi and T. simpsoni . At the end of the Miocene, the particularly small species T. polkensis appeared.

### Pliocene and Pleistocene

Skull of Tapirus augustus

The tapirs of Europe disappeared again at the end of the Pliocene 2.7 million years ago, which is seen as a result of the cooling and stronger seasonal fluctuations in the climate and the associated spread of open landscapes. In East and Southeast Asia, however, the animals lived on, the early Miocene form, T. yunannensis , split up into several lines here. Thus evolved T. PEII about T. sinensis to T. augustus , also known Megatapirus known a horse large animal that was the greatest of all time Tapir. This line contrasts with the developmental sequence from T. sanyuanensis to T. indicus (Schabrackentapir). While most species are restricted to the Early and Middle Pleistocene, T. augustus , apart from the black-backed tapir, can also be found up to the Late Pleistocene and was possibly still to be found in the early Holocene .

In North America, the small T. polkensis is still handed down during the Pliocene . In the early Pleistocene, T. haysii and T. lundaliusi largely dominated , both were then replaced by T. veroensis . This tapir species was most likely to be found in North America until the first humans appeared, but died out shortly afterwards. The tapirs came to South America, the focus of their current distribution area, relatively late in the course of the Great American Fauna Exchange after the creation of a land bridge through the closure of the Isthmus of Panama , the oldest records here are around 2.5 million years old. The fossil South American representatives of the tapirs include T. rondoniensis , T. rioplatensis , T. oliverasi , T. tarijensis , T. cristatellus and T. mesopotamicus . All of these forms are monophyletically related and thus go back to an ancestral form. As a result, they are much closer to the lowland and mountain tapirs than to the Central American tapir.

Tapirs were and are typically inhabitants of dense forests. Therefore the expansion of large grasslands in the Neogene was not favorable for them. From the once species-rich family, only the five species today survived; the last major extinction event, to which some tapir forms also fell victim, was the Quaternary extinction wave .

## Taxonomy

Mathurin-Jacques Brisson

The word tapir comes from the Tupí language from Brazil , who called the animals Tapira-caaivara , which translates on the one hand as " bush ox ", but on the other hand also refers to the hidden way of life of the animals. The term danta or anta, which is often used especially in South America, is a borrowing from the Spanish language and originally referred to the elk. In Southeast Asia, the tapir is called badak in Malay and som-set in Thai .

Linnaeus referred the tapir to the hippopotamus in his work Systema Naturae in 1758 because of its physique and named the lowland tapir, the only tapir species known in Europe at the time, as Hippopotamus terrestris . The French naturalist Mathurin-Jacques Brisson first introduced the term tapir in French in his work Regnum animale ( le tapir ) in 1762 . The Danish zoologist Morten Thrane Brünnich first used the generic name Tapirus , which is valid today ; for a long time he was the first to describe the genus. Brünnich used the term, which he derived from Brisson's name le tapir , for the first time in 1772. The British paleontologist Arthur Tindell Hopwood proposed Brisson as the original descriptor in 1947, which then led to numerous discussions in the professional world, as Brünnich was preferred by the majority at the time. In 1998, however, a plenary meeting of the ICZN decided to define Brisson as the first to describe the genre, which is widely accepted today.

## Tapirs and people

Tapir in the zoo

In some regions, tapirs are hunted for their meat and skins, but there are also indigenous tribes that do not hunt tapirs for religious reasons. Today, hunting is not so much the reason for the decline in the numbers of four IUCN- managed tapir species as the destruction of their habitat - above all the rapid loss of tropical forests through felling and slash-and- burn . Added to this is the increasing competition with large animals used for agriculture.

The IUCN lists three of the five species, the mountain tapir , the Central American tapir and black-backed tapir , as endangered and the lowland tapir as endangered ( vulnerable ). The size of the population of the lowland tapir is unknown, the population of the mountain tapir comprises around 2500 individuals and that of the Central American tapir around 5500 animals. It is critical to the saddleback tapir, of which only 1500 to 2000 animals are accepted. There are numerous conservation projects that are coordinated by the IUCN's Tapir Specialist Group . In addition to observing the animals in national parks and other protected areas, the aim is also to relocate endangered populations , sometimes with the help of camera traps .

Tapirs, mostly lowland tapirs, are often kept in zoos. In some regions of South America, tapirs are also used as pets.

## literature

• Ronald M. Nowak: Walker's Mammals of the World . The Johns Hopkins University Press, Baltimore 1999, ISBN 0-8018-5789-9 .
• Sheryl Todd, Udo Ganslosser: The tapirs . Filander, 1997, ISBN 3-930831-41-4 .
• James Oglethorpe: Tapirs: Status, Survey, and Conservation Action Plan . IUCN, 1997, ISBN 2-8317-0422-7 .
• Stefan Seitz: Comparative studies on the behavior and display value of tapirs (Tapiridae) in zoological gardens . Cuvillier, 2001, ISBN 3-89873-201-0 .
• Sy Montgomery: "The Tapir Scientist". Houghton Mifflin, 2013, ISBN 978-0-547-81548-0 .

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