ORIGIN AND EVOLUTION OF MAMMOTHS


     GENEALOGICAL TREE OF PROBOSCIDEA
     The history of Proboscidea - group of mammals, which includes mammoth and elephants - one of most complex in systematic of fossil mammals. Proboscidea are known about 40 mln. years before) up to our days. Mammoths and elephants are the representatives of one family among several families of Proboscidea. All these animals were incorporated by the term "trunk", that in translation means a forward mouth.
     The organ like trunk developed from earliest Proboscidea. Among modern animals to Proboscidea the Sirenia (large sea mammals) and Hyracoidea (small mammals, living in Africa) are closest. At these mammals is not present a trunk, but on some features of a structure of a skeleton and teeth they are similar with Proboscidea.

Moeritherium
    MORITHERIUM. The most ancient of known Proboscidea. The fossil remanes of Moritherium are found in Northern Africa, their age about 40 millions years (Late Eocene). It were small, up to 1 meter in height, animal - amphibians. Moritherium have appeared a deadlock branch in evolution of Proboscidea.
 

Deinotherium    DEINOTHERIUM. Ancient Proboscidea, arisen in Africa in Miocene about 24 millions years ago. In Pleistocene were widespread in Eurasia. Into Northern America did not penetrate. Have died out about 2 millions years ago. Original tusks were only in mandible. During evolution deinotherium became larger, up to 4 meters in height. A lateral branch of evolutionary development of Proboscidea.
 
 
 
 

Palaeomastadon   PALAEOMASTODON. Are known only from Late Eocene (40 millions years ago) Northern Africa. One of most ancient Proboscidea,a beginning to families Gomphotheria and Mastodontidae. Tusks had small, oval in section, both in top and in bottom jaws. Between of tusks and cheek teeth was available diastema (interval). Trunk small. From all ancient Proboscidea palaeomastodon more others are similar to modern elephants.
Ambelodon   AMEBELODON. Amebelodon - the genus of mastodon belonging to family Gomrhotheriidae, was usual in Northern America in Late Miocene (about 24 millions years ago). Top tusks were small, while bottom - large size and plantical. Probably bottom tusks amebelodon dug out roots of plants.
 

Platibeladon  PLATIBELEDON. Fossil remains of platibelodon were found for the first time only in 1920 in Miocene deposits (about 20 millions years ago)in Asia. In the mandibule original tusk like spade, excellently adapted to extraction of water and marsh vegetation, with which ate platibelodon. In it platibelodon is comparable with American amebelodon.
 

Gomphotherium   GOMPHOTHERIUM. Gonphotherium - mastodon, usual in Africa about 20 millions years ago, was settled from Africa through Europe in Asia down to Indostan. Equally were well advanced top and bottom tusks. Lived most likely in humidified, marshy landscapes, for the benefit of what speak strongly lengthened to a jaw.

Mastodon   MASTODONT. The separate family Mastodontidae, has arisen in Middle Oligocene (30 millions years ago) in Africa. The representatives of this family were settled on all Africa, Eurasia and America in Miocene (about 24 millions years ago). Mastodons were kept in Northern America up to the end Pleistocene. The age of some fossil remains of mastodont only 10.000 years, that meets to time of development like culture of primitive inhabitant of North America. It were large Probocsidea, at which the chewing surface of cheek teeth was covered with lines large hills. At mastodont were large top tusks and, occasionally, at male, small bottom. It is possible, that the disappearance of mastodont was promoted by a hunt on them ancient primitive inhabitant of North America.

Stegodon   STEGODON. Stegodon - representatives of separate family close the relatives to family of elephants (where enters and mammoth). The most ancient finds in Asia are dated 8 millions years (End Miocene). Were settled on Europe and Africa later. By the sizes were similar to modern elephants, top tusks were long and massive. Ate stegodon branches and foliage of trees.

Primelephas   FIST ELEPHANT (PRIMELEPHAS). The family of elephants - Elephantidae, includes of mammoth and nowadays living elephants. As against mastodons, cheek teeth at the representatives of this family with cross crests, and tusks without enamel. The most primitive representative of family is Primelephas, which probably is a direct ancestor of mammoths and modern elephants. It fossil remains are found in Central Africa and are dated the End Miocene - 5 millions years ago. A probable place of living of Primelephas was wood areas. The sizes of Primelephas are compared to a modern Indian elephant - height in shoulders about 3 meters. As against other elephants at Primelephas were small tusks in the bottom jaw.

Mammuthus meridionalis   SOUTHERN ELEPHANT (ARCHIDISKODON MERIDIONALIS). The most ancient finds of mammoths occur in Early Pliocene of East and Southern Africa about 4 millions years ago. Just in the south of Africa there was most favorable landscape conditions for existence of mammoths. Usually mammoth allocate in separate subfamily Mammuthinae, which is characterized by a skull with circle by top, without ÓÅÄÌÏ×ÉÄÎÏÇÏ ×ÄÁ×ÌÅÎÉÑ. The bones between mandible are narrowed from sides in the average part. The tusks have spiral curved. The evolution of mammoth went on a way of the adaptation to inhabit in conditions steppe and forest-steppe of landscapes. First mammoth belonged to a genus Archidiskodon. The representatives of this genus were settled from Africa in Eurasia and Northern America. In Pleistocene these mammoth have generated uniform Eurasia-American Ariel, after penetration of a southern elephant (Archidiskodon meridionalis) in Northern America of 1.5 million years ago. In territory of Eurasia the southern elephant is a direct ancestor steppe mammoth and Mammuthus primigenius. In Northern America, in opinion of many experts, the southern elephant has become an ancestor of Colombian mammoth. First mammoths were large elephants of height up to 4.5 meters in shoulders.

Mammuthus Trogonterii   STEPPE MAMMOTH (MAMMUTHUS TROGONTHERII). Direct descendant of a southern elephant in territory of Eurasia has become steppe mammoth Mammuthus trogontherii. It was the huge elephant, height up to 5 meters. The mineral rests are known with early Pleistocene from steppe and forest-steppe of zones of Eurasia. Probably to the same kind belongs Middle Pleistocene Hazaricus mammoth, which is a transitive part from steppe mammoth to Mammuthus primigenius. The significant climatic changes come in Eurasia in Middle Pleistocene and which have expressed in cold and strengthening worm, have resulted in a wide circulation of an opened landscape such as arctic steppe, tundra and forest-tundra’s. Under influence changes of natural conditions mammoths were compelled to adapt to a feed rigid grassy and bushes by vegetation.

Mammuthus columbi   COLOMBIAN MAMMOTH. Colombian mammoth inhabited in Northern America on the Middle and Late Pleistocene. On a degree of evolution corresponded Eurasian steppe mammoth, however, was kept in America almost up to the End Pleistocene. Its sizes strongly varied from dwarfs on islands Channel (California), height about 1.8 meters, up to the giants, height 4-4.5 meters in southern areas of Northern America. By the End Pleistocene there were isolated populations Colombian mammoth, smaller under influence of isolation and described as Dzefersons mammoth. Finally mammoths in America have disappeared 12 thousands years ago, not without the help primitive inhabited of North America.

Mammuthus primigenius   MAMMOTH IN TUNDRA. Systematic is a classification of animals to related attributes. Many forms of Mammuthus primigenius of a different rank are described, which systematic situation is not clear. Besides in stratigraphic two not designated forms quite often are specified: early and late, that causes mess in systematic. Except subspecies Mammuthus primigenius primigenius, inhabited in the End Pleistocene in Northern Eurasia, it is possible to specify still only one Holocene subspecies from an Vrangels island - Mammuthus primigenius Vrangeliensis. As a whole subspecies systematic of mammoth is developed not enough more and requires auditing. On morphology of teeth and skeleton mammoths are closer to modern Asian elephants, but not to African.

Elephas maximus   ASIAN ELEPHANT (ELEPHAS MAXIMUS). Isolated populations of Asian or Indian elephants (Elephas maximus) inhabited in Southern and South-East Asia. In some countries on the verge of disappearance (China, Nepal, Bangladesh). Weight of adult elephants of 3-5 tons, height in shoulders 2-3.5 meters. Inhabited basically in woods, eating branch and foliage. At female practically is not present tusks, tusks of male the lengths of 2 meters reach. There are three subspecies of an Asian elephant - elephants of an island Sri-Lanka, elephants of an island Sumatra and continental subspecies.
The Asian elephant is very obedient and is clever. Frequently is used as a home animal for moving weights and other works on Sri-Lanka and in South-East Asia. The usual participant of circus representations and inhabited of zoos.
 

Loxodonta africana   AFRICAN ELEPHANT (LOXODONTA AFRICANA). The African elephant - largest ground animal, adult male weight up to 7 tons, reaching in height of 4 meters. Inhabited in Central and Southern Africa. Distinguish two subspecies - steppe and wood. First subspecies lives in opened steppe and deserts (Namibia), eating in the basic grass. The wood elephant lives in jungle, fed brunches of trees and bushes, and water vegetation. A steppe elephant is larger wood. Tusk have female and male elephant, at male they huge, up to 3.5 meters in length and weight up to 100 kg.
A line of analogies connecting landscapes tundra-steppe of Pleistocene of Eurasia and steppe of Africa is established. For example, the African elephants, destroying wood vegetation, promote formation of steppe. As well, mammoths expanded area tundra-steppe, trample down bushes and breaking trees. Thus, these giants created conditions of life for tens others inhabits of opened spaces.


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