Mammutidae
Skeletal reconstruction of a mastodon
The Real mastodons or Mammutiden ( Mammutidae ) are an extinct family of mammoths ( Proboscidea ) from the Neogene and Quaternary. Within this, they represent a very primitive form; they were spread all over the Old World to America and died there until the end of the Pleistocene about 10,000 years ago from.
Description
The conformation of the Real Mastodons resembled that of the elephant, but was longer and lower. Characteristic was the sloping forehead. As the gomphotheres had the rights mastodons significantly zygodonte molars, which consisted of individual strips, each with a teat-shaped tooth enamel cusps at their ends. The primary molars and the first two Dauermolaren each had three bars ( trilophodont ), while the last four molars possessed. The dental morphology suggests a leaf -eating diet. Early representatives of the Real mastodons still had four tusks, one pair each in the upper and lower jaw, which, as with all proboscidean from the respective second incisor were each mandibular arch. Late forms reported only on maxillary tusks, while the lower were reduced by the shortening of the mandible and later no longer be trained.
Development and species
The first genuine mastodons evolved in Africa from the Palaeomastodon. Molecular Genetics Research suggests they split already in the upper Oligocene 26 million years of the development line to today's Real elephants from. The first fossil record with Eozygodon comes from the lower Miocene epoch, about 22 million years ago. For this later Zygolophodon developed. This tusker genus reached approximately 20 million years, with the gradual closure of the Tethys Ocean and the formation of a land bridge between Africa and the northern continental masses also Eurasia and ultimately America. They had four tusks, the upper were bent downward, while the much smaller lower a straight course had. In the course of development, but reduced the lower tusks, while the molars assumed a more zygodonte form. In Central Europe finds the type Zygolophodon turicensis are known from Elgg (Canton Zurich ) and Esselborn ( Rhineland -Palatinate).
The mastodons from the late Miocene around 10 million years ago starting of the genus attributed mammoth. This had only two upper tusks. The genus name may lead to confusion with mammoth Mammuthus, the generic name of the mammoth, an extinct group of elephants ( Elephantidae ). One of the greatest forms was the Eurasian species Mammut borsoni from the Miocene and the Pliocene. It reached a shoulder height of 3.5 to nearly 4 m. Of note is the extremely long, hardly curved tusks of this type are A recently discovered skeleton of Macedonia ( Greece) pointed tusks with a length of 4.5 m. From Germany comes finds from Kaltensundheim ( Thuringia), where in 1958 a partial skeleton and 1976-1978, a nearly complete skeleton was recovered. With mammoth borsoni died in Eurasia in the early Pleistocene million years ago, about 2.5 to 2, the last representative of the rights of mastodons. The extinction of mammoths is explained by the increasing during this time cooling of the climate and the spread of steppes in Eurasia, the fasted basic specialized leaf -eaters.
In America, but the mastodons existed much longer. The American mastodon (Mammut americanum ) lived until about 10,000 years ago in North America and one of the last members of a whole group of primitive proboscis animals. It reached a shoulder height of about 2.5 m and had as an adaptation to the cool to cold climate, a coat. The tusks were swung clear upward. Proved it is from numerous sites in Canada and the U.S., but also from some places in Central America, as finds from Mexico and Honduras show.
System
Originally, the rights mastodons were grouped together with the gomphotheres to the superfamily of mastodons ( Mastodontoidea ). This classification is no longer valid today. You now belong within the group of Elephantiformes to the superfamily Mammutoidea, which represents the urtümlichere sister group of the family Gomphotherioidea ( with the gomphotheres ). From the latter evolved over the Stegodonten ( Stegodontidae ) the rights elephants ( Elephantidae ) with the still existing genres. These two trunk groups of animals belong to the superfamily Elephantoidea.
To the family of Real mastodons following genera include:
- Eozygodon ( Tassy and Pickford 1983)
- Zygolophodon ( Vacek 1877)
- Mammoth ( Blumenbach, 1799)
Naming
Mastodon The name derives from the Greek μαστός ( mastos, teat or breast) and οδον ( odon, tooth) ago and refers to the special tooth construction. It was introduced officially in 1817 by the French paleontologist Georges Cuvier. He used it for an animal that angustidens now known as Gomphotherium and is attributed to the more modern proboscidean from the group of gomphotheres. Because of this term is now rarely used in the literature and usually refers to the American mastodon, as Rüsseltier group called Real mastodons of professionals Mammutiden. The name Mammut (not to be confused with Mammuthus, the genus of the mammoths ), from which is derived the technical term goes back to Johann Friedrich Blumenbach, who first mentioned in his Manual of Natural History from the year 1799 the American mastodon as mammoth ohioticum.