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18.12.2015 16:50 - Largest prehistoric animals vol.1Vertebrates part1 Mammals ch.15 Bisons and other Bovines and Bovidaes
Автор: valentint Категория: Забавление   
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Bisons and other Bovines and Bovidaes
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From left to right : Long-horned Bison(extinct), Pelorovis Antiquus(extinct), Ancient Bison(extinct), Steppe Bison(extinct), Aurochs(extinct), Holocene Bison(extinct), Cebu dwarf Buffalo(extinct), Pelorovis Oldowayensis(extinct), Gaur, Asiatic Buffalo, Wild Yak, American Bison, European Bison, Cape Buffalo and the last but not least,our friendly innocent domestic cattle.

With 143 extant species and 300 known extinct species, the family Bovidae consists of eight major subfamilies apart from the disputed Peleinae and Pantholopinae. The family evolved 20 million years ago, in the early Miocene.
The present classification scheme for bovids recognizes eight subfamilies subdivided into two clades, the Boodontia (with a single subfamily, Bovinae) and Aegodontia (composed of all other bovid subfamilies). Some authors do not recognize these two clades, instead reducing the number of subfamilies to two: Bovinae (without change) and Antilopinae (with all of the Aegodontid subfamilies as tribes within it). Among the eight subfamilies presented here, the phylogeny of some groups is well-established (e.g., the Bovinae are monophyletic and basal; the Caprinae, Hippotraginae, and Alcelaphinae cluster together consistently), while the interrelationships of the other subfamilies are still under question.
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The family Bovidae began its evolution in Africa around 19 million years ago, and rapidly diversified, with 78 genera known from the Miocene (compared to 50 today). Kingdon (1997) suggests that a continental divide between Africa and Eurasia may be responsible for the early divergence of the Boodontia (Eurasian in origin) and the Aegodontia (which continued evolving in Africa).The rejoining of the two continental land masses (after these two principal clades had become distinct) at the Arabian peninsula removed this geographic barrier, allowing both groups to expand into the other"s homeland.
In the early Miocene, bovids began diverging from the cervids (deer) and giraffids. The earliest bovids, whose presence in Africa and Eurasia in the latter part of early Miocene (20 Mya) has been ascertained, were small animals, somewhat similar to modern gazelles, and probably lived in woodland environments.Eotragus, the earliest known bovid, weighed 18 kg (40 lb) and was nearly the same in size as the Thompson"s gazelle.Early in their evolutionary history, the bovids split into two main clades: Boodontia (of Eurasian origin) and Aegodontia (of African origin). This early split between Boodontia and Aegodontia has been attributed to the continental divide between these land masses. When these continents were later rejoined, this barrier was removed, and either group expanded into the territory of the other.The tribes Bovini and Tragelaphini diverged in the early Miocene.Bovids are known to have reached the Americas in the Pleistocene by crossing the Bering land bridge.
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The present genera of Alcelaphinae appeared in the Pliocene. The extinct Alcelaphine genus Paramularius, that was the same in size as the hartebeest, is believed to have come into being in the Pliocene, but became extinct in the middle Pleistocene.Several genera of Hippotraginae are known since the Pliocene and Pleistocene. This subfamily appears to have diverged from the Alcelaphinae in the latter part of early Miocene.The Bovinae are believed to have diverged from the rest of the Bovidae in the early Miocene.The Boselaphini became extinct in Africa in the early Pliocene; their latest fossils were excavated in Langebaanweg (South Africa) and Lothagam (Kenya).
The middle Miocene marked the spread of the bovids into China and the Indian subcontinent. According to Vrba, the radiation of the subfamily Alcelaphinae began in the latter part of middle Miocene.The Caprinae tribes probably diverged in the early middle Miocene. The Caprini emerged in the middle Miocene, and seem to have been replaced by other bovids and cervids in Eurasia.The earliest fossils of the antilopines are from the middle Miocene, though studies show the existence of the subfamily from the early Miocene. Speciation occurred in the tribe Antilopini during the middle or upper Miocene, mainly in Eurasia. Tribe Neotragini seems to have appeared in Africa by the end of Miocene, and had become widespread by the Pliocene.
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1. Makapania 2. Preptoceras 3. Gallogoral  4. Palaeoreas 5. Euceratherium
By the late Miocene, around 10 Mya, the bovids rapidly diversified, leading to the creation of 70 new genera.This late Miocene radiation was partly because many bovids became adapted to more open, grassland habitats.The Aepycerotinae first appeared in the late Miocene, and no significant difference in the sizes of the primitive and modern impala has been noted.Fossils of ovibovines, a tribe of Caprinae, in Africa date back to the late Miocene.The earliest Hippotragine fossils date back to the late Miocene, and were excavated from sites such as Lothagam and Awash Valley.The first African fossils of Reduncinae date back to 6-7 Mya.Reduncinae and Peleinae probably diverged in the mid-Miocene.


Bisons

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Bison latifrons,Bison antiquus,Bison priscus,Bison bison

Bison latifrons

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Bison latifrons reached a shoulder height of 2.5 meters (8.2 feet), and had horns that spanned over 2 meters (6.6 feet). B. latifrons reached a shoulder height of 2.5 meters (8.2 ft) and may have weighed over 2,000 kilograms (4,400 lb). It competes with the "giant Africa buffalo" Pelorovis for the title of largest bovid, and even largest ruminant ever to live, possibly outweighing the extant African giraffe (Giraffa camelopardis). The horns of B. latifrons measured as great as 213 centimeters (84 in) from tip to tip, compared with only 66 centimeters (26 in) in modern Bison bison. The known dimensions of the species are much larger than any extantbovid, including both extant species of bison — the American bison and the European bison. Based on a comparison of limb bones between B. latifrons and B. bison, the mass of the former is estimated to have been 25%–50% greater than that of the latter. In fact, B. latifrons is possibly the largest bovid in the fossil record.
B. latifrons is thought to have evolved in midcontinent North America from Bison priscus, another prehistoric species of bison which migrated across the Bering land bridge between 240,000–220,000 years ago. B. latifrons was one of many species of North American megafauna which became extinct during the transition from the Pleistocene to the Holocene epoch (an event referred to as the Quaternary extinction event). It is thought to have disappeared some 21,000–30,000 years ago, during the late Wisconsin glaciation. The species was replaced by the smaller Bison antiquus, which in turn evolved into the yet smaller Bison bison — the modern American bison — some 10,000 years ago.
An herbivore, B. latifrons is believed to have lived in small family groups, grazing in the Great Plains and browsing in the woodlands of North America. Paleontologists believe it preferred the warmer climes of what"s now the United States, and fossils of the species have been found as far south and west as modern-day San Diego, California. The large, thick horns of the males are believed to have been employed as a visual deterrent to large carnivorous megafauna such as the saber-toothed cat and short-faced bear and also to establish dominance in battle with other males for the right to mate.


Bison antiquus (Ancient bison)
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Bison antiquus, sometimes called the "ancient bison", was the most common large herbivore of the North American continent for over ten thousand years, and is a direct ancestor of the living American bison.
During the later Pleistocene epoch, between 240,000 and 220,000 years ago, steppe wisent (B. priscus), migrated from Siberia into Alaska. This species inhabited parts of northern North America throughout the remainder of the Pleistocene. In midcontinent North America, however, B. priscus was replaced by the long-horned bison, B. latifrons, and somewhat later by B. antiquus. The larger B. latifrons appears to have died out by about 20,000 years ago. In contrast, B. antiquus became increasingly abundant in parts of midcontinent North America from 18,000 ya until about 10,000 ya, after which the species appears to have given rise to the living species, B. bison. B. antiquus is the most commonly recovered large mammalian herbivore from the La Brea tar pits.
B. antiquus was taller, had larger bones and horns, and was 15-25% larger overall than modern bison. It reached up to 2.27 m tall, 4.6 m  long, and a weight of 1,588 kg. From tip to tip, the horns of B. antiquus measured about 3 ft (nearly 1 m).
One of the best educational sites to view in situ semifossilized skeletons of over 500 individuals of B. antiquus is the Hudson-Meng archeological site operated by the U.S. Forest Service, 18 miles (29 km) northwest of Crawford, Nebraska. A number of paleo-Indian spear and projectile points have been recovered in conjunction with the animal skeletons at the site, which is dated around 9,700 to 10,000 years ago. The reason for the "die-off" of so many animals in one compact location is still in conjecture; some professionals argue it was the result of a very successful paleo-Indian hunt, while others feel the herd died as a result of some dramatic natural event, to be later scavenged by humans. Individuals of B. antiquus of both sexes and a typical range of ages have been found at the site.
According to internationally renowned archaeologist George Carr Frison, B. occidentalis and B. antiquus, an extinct subspecies of the smaller present-day bison, survived the Late Pleistocene period, between about 12,000 and 11,000 years ago, dominated by glaciation (the Wisconsin glaciation in North America), when many other megafauna became extinct. Plains and Rocky Mountain First Nations peoples depended on these bison as their major food source. Frison noted that the "oldest, well-documented bison kills by pedestrian human hunters in North America date to about 11,000 years ago."


Bovids
Pelorovis antiquus
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Pelorovis ("prodigious/monstrous sheep") is an extinct genus of African wild cattle, which first appeared in the Pliocene, 2.5 million years ago and became extinct at the end of the Late Pleistocene about 12,000 years ago or even during the Holocene, some 4,000 years ago.Recent detailed anatomical and morphometric studies come to the conclusion that Pelorovis is probably not monophyletic. According to these findings, the early forms of the genus (P. turkanensis und P. oldowayensis) are close relatives, and possibly the first members, of the genus Bos. In contrast, the late Pleistocene form (Pelorovis antiquus) seems to be a close relative of the modern African buffalo (Syncerus caffer).
Pelorovis resembled an African buffalo, although it was larger and possessed longer, curved horns. Pelorovis probably weighed about 1,200 kilograms (2,600 lb), with the largest males attaining 2,000 kilograms (4,400 lb). This ranks it as one of the largest bovines, and indeed ruminants ever to have lived, rivaling the extinct American long-horned bison (Bison latifrons) and the extant African giraffe (Giraffa camelopardis). The bony cores of the horns were each about 1 metre (3.3 ft) long; when covered with keratin (which does not survive fossilisation) they could have been up to twice this length.The horns pointed away from the head, each forming a half circle in the species Pelorovis oldowayensis and Pelorovis turkanensis.
The horns of Pelorovis antiquus were also magnificent but resembled in shape more those of the Water buffalo (Bubalus). P. antiquus was even placed in the Genus Bubalus by early specialists. Pelorovis oldowayensis was broadly the same size as modern African buffalo, but its legs were longer, and the elongated head of this species was reminiscent to those of the modern Alcelaphinae. Pelorovis antiquus was about the same size, but it was more robust.
Pelorovis antiquus disappeared around 12,000 years ago from southern and eastern Africa. Fossil and archaeological evidence indicates that this species lived in North Africa until 4,000 years ago.Pelorovis oldowaywensis occurred in sub-Saharan Africa and disappeared 800,000 years ago.
The best fossils of Pelorovis oldowayensis are known from the Olduvai Gorge in Tanzania; a complete skeleton of Pelorovis antiquus was found near Djelfa in Algeria.


Bos primigenius
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The largest extinct bovid is Aurochs (Bos primigenius) with an average height at the shoulders of 155–180 cm (61–71 in) in bulls and 135–155 cm (53–61 in) in cows, while aurochs populations in Hungary had bulls reaching 155–160 cm (61–63 in). The aurochs was variously classified as Bos primigenius, Bos taurus, or, in old sources, Bos urus. However, in 2003, the International Commission on Zoological Nomenclature "conserved the usage of 17 specific names based on wild species, which are pre-dated by or contemporary with those based on domestic forms", confirming Bos primigenius for the aurochs. Taxonomists who consider domesticated cattle a subspecies of the wild aurochs should use B. primigenius taurus; those who consider domesticated cattle to be a separate species may use the name B. taurus, which the Commission has kept available for that purpose.
The words aurochs, urus, and wisent have all been used synonymously in English. However, the extinct aurochs/urus is a completely separate species from the still-extant wisent, also known as European bison. The two were often confused, and some 16 th-century illustrations of aurochs and wisents have hybrid features. The word urus (/ˈjʊərəs/; plural uri)is a Latin word, but was borrowed into Latin from Germanic (cf. Old English/Old High German ūr, Old Norse ъr). In German, OHG ūr was compounded with ohso "ox", giving ūrohso, which became early modern Aurochs. The modern form is Auerochs.

The word aurochs was borrowed from early modern German, replacing archaic urochs, also from an earlier form of German. The word is invariable in number in English, though sometimes back-formed singular auroch and innovated plural aurochses occur. The use in English of the plural form aurochsen is nonstandard, but mentioned in The Cambridge Encyclopedia of the English Language.It is directly parallel to the German plural Ochsen (singular Ochse) and recreates by analogy the same distinction as English ox (singular) and oxen (plural).
During the Pliocene, the colder climate caused an extension of open grassland, which led to the evolution of large grazers, such as wild bovines. Bos acutifrons is an extinct species of cattle that has been suggested as an ancestor for the aurochs.

The oldest aurochs remains have been dated to about 2 million years ago, in India. The Indian subspecies was the first to appear. During the Pleistocene, the species migrated west into the Middle East (western Asia) as well as to the east. They reached Europe about 270,000 years ago. The South Asian domestic cattle, or zebu, descended from Indian aurochs at the edge of the Thar Desert; the zebu is resistant to drought. Domestic yak, gayal and Javan cattle do not descend from aurochs.
The first complete mitochondrial genome (16,338 base pairs) DNA sequence analysis of "Bos primigenius" from an archaeologically verified and exceptionally well preserved aurochs bone sample was published in 2010.
Three wild subspecies of aurochs are recognized. Only the Eurasian subspecies survived until recent times.
The Eurasian Aurochs (Bos primigenius primigenius) once ranged across the steppes and taigas of Europe, Siberia, and Central Asia. It is noted as part of the Pleistocene megafauna, and declined in numbers along with other megafauna species by the end of Pleistocene. The Eurasian aurochs were domesticated into modern taurine cattle breeds around the 6th millennium BC in the Middle East, and possibly also at about the same time in the Far East. Aurochs were still widespread in Europe during the time of the Roman Empire, when they were widely popular as a battle beast in Roman arenas. Excessive hunting began and continued until the species was nearly extinct. By the 13th century, aurochs existed only in small numbers in Eastern Europe, and the hunting of aurochs became a privilege of nobles, and later royal households. The aurochs were not saved from extinction, and the last recorded live aurochs, a female, died in 1627 in the Jaktorуw Forest, Poland from natural causes. Aurochs were found to have lived on the island of Sicily, having migrated via a land bridge from Italy. After the disappearance of the land bridge, Sicilian aurochs evolved to be 20% smaller than their mainland relatives (Island dwarfism).


Euceratherium collinum
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The shrub-ox (Euceratherium collinum) is an extinct genus and species of Bovidae native to North America.
Euceratherium was one of the first bovids to enter North America. It appeared on this continent during the early Pleistocene, long before the first bison arrived from Eurasia. It became extinct about 11,500 years ago.
Late Pleistocene shrub-ox remains are known from fossil finds spanning from northern California to central Mexico. In the East they were distributed at least into Illinois.
Euceratherium was massively built and in size between a modern American bison and a musk ox. A specimen was estimated to have a body mass of 700 kg.  On the basis of preserved dung pellets, it has been established that they were browsers with a diet of trees and shrubs.  They seem to have preferred hilly landscapes.




 

 


 


 

 


 



Тагове:   сова,   prehistoric animals,   giant animals,   encyclopedia,   ancient bison,   bovids,   aurochs,   urus,   wisent,


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Автор: valentint
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