Mammuthus creticus

Crete - dwarf mammoth (Mammuthus creticus )

• Crete

The Crete - dwarf mammoth (Mammuthus creticus ) lived at the transition from the older to middle Pleistocene around 740,000 years ago in Crete and is the smallest known today Mammutart dar. skeletal remains are relatively rare, the size and weight calculations are based on molar teeth and long bones.

Features

Finds of Crete dwarf mammoths comprise largely only fragmented bone material. Skull finds are not delivered, are known especially the molars. These are about 13.9 to 14.5 cm long, 3.3 to 3.7 cm wide in adult individuals and have 10 to 12 Melting wrinkles on the Kauoberfläche. Furthermore postcranial skeletal elements such as ribs, vertebrae and long bones occur. A humeral an adult animal has a length of 33 cm. Mainly due to this find a shoulder height of about 1.13 m for the Crete - dwarf mammoth reconstructed and calculated a body weight of approximately 310 kg. This is one of the Crete - dwarf mammoth among the smallest known representatives of the elephants ( Elephantidae ).

Size comparisons

The finds from Crete show a typical Inselverzwergung entering the mainland territory and the resulting limited food supply, but also lack of predators in the separation of populations originally großwüchsiger animals. This is proven several times in the line of elephants ( Elephantidae ). With the given values, the size of Crete dwarf mammoth is the smallest known Mammutart the world. Among the other elephants were merely the Sicilian dwarf elephant ( Elephas falconeri ) and the Cyprus Dwarf Elephant (Elephas cypriotes ), both from the Upper Pleistocene, smaller. The Sicilian dwarf elephant occurred in Malta and Sicily and a maximum of 1 m was high, with a weight of 170-240 kg, while the Cyprus dwarf elephant weighed about 250 kg. Both are descendants of the European forest elephant (Elephas antiquus ), which was up to 4.2 m tall and weighed around 11 tons.

Among the mammoth is the proven Sardinia medium to jungpleistozäne kind Mammuthus lamarmorai with a shoulder height of 1.5 m and a weight of 800 kg, the next larger shape. The dwarfed woolly mammoth (Mammuthus primigenius ) from Wrangel Island in the Arctic Ocean, which dates to the middle Holocene and so on recent mammoth finds are ever the other hand, had a shoulder height of 1.8 m, with a weight of just over 2 tons. Even larger were the also surviving to the Mittelholozän woolly mammoth from the Pribilof Islands off the coast of Alaska that were only slightly dwarfed. The dwarf mammoth Mammuthus exilis the nature of the Channel Islands off the coast of California, the (Mammuthus columbi ) may be derived from the prairie mammoth and also have a jungpleistozänes age, extremely varied in size, so that the shoulder height between 1.2 and 1.8 m.

An adult "normal" woolly mammoth had a shoulder height of 2.6 to 3.7 m and weighed an average of 5 to 6 t. While both the Südelefant (Mammuthus meridionalis ) and the prairie mammoth had a shoulder height of 4 m and a good 10 tonnes placed on the scale, the largest mammoth and also the biggest known today tusker was the steppe mammoth (Mammuthus trogontherii ), which up to 4, 5 m high was (without soft tissue) and was estimated to reach a weight of up to 15 t.

Finds

The majority of the finds of the Crete - dwarf mammoth comes from the Cape Maleka ( ⊙ 35.58694444444424.175 ) on the Akrotiri peninsula in the northwest of Crete. These usually include findings of molars, but also ribs and long bones. First finds, predominantly molars came here in 1905 to days and were used for initial description of the type Other finds come from 1973 and were made by the Dutch paleontologist Paul Sondaar. The last date discoveries reach 2011, including molars and an upper arm bone. Due to the accompanying artefacts with the rodent Kritimys kiridus an age in the transition from Old - to Middle Pleistocene was adopted for the finds, which has been generally indicated by 800,000 years. Because geophysical studies is now assumed an age of 738,000 years.

System

In her first, in 1907, published analysis based on some discoveries, which included nine molars, some tusk fragments and a fractured vertebra, Dorothea Bate said the finds from the Cape Maleka as Elephas creticus. Here, a rear molar tooth is considered as lectotype of the type ( copy number NHM M 9381 ). The Crete - dwarf mammoth was mostly due to the assumed relationship with the European forest elephant and his then assignment to Palaeolxodon as Elephas ( Palaeoloxodon ) creticus called. For irritations but also caused the occurrence of two other Pleistocene species of elephants on Crete, which were assigned to the species Elephas Elephas priscus and Creutz burg, but much younger and above all were larger and are usually incorporated into the European forest elephants.

Due to the age of the finds and the earliest occurrence of the European forest elephants in Europe partially doubts about such a relationship came up, in 1996, had the Dutch palaeontologist Dick Mol on a possible relationship with the mammoths back. However, Bate had recognized similarities to the mammoths in their first description in 1907, especially for Südelefanten, but she described as Elephas meridionalis. Molecular genetic studies in 2006 then brought further evidence of descent from Mammuthus. This study, however, was heavily criticized later due to the high age of the finds, the only small number of investigated DNA base pairs ( 43 bp) and methodological errors.

New analyzes from 2011 to neugefundenem material confirmed the assignment to the mammoths, where especially the molars were used. These are wider at Mammuthus in relation to the length as in Elephas. In addition, the molars of mammoths have also substantially narrower and often continuous melting wrinkles with clear parallel edges, in contrast to those of the representatives of Elephas whose melting wrinkles are more divided in the middle area and have more bulged edges.

Phylogeny

Theoretically come for the origin of Crete dwarf mammoths both the Südelefant and the steppe mammoth in question. The former developed more than three, the latter in front of a half million years. Due to the structure of the molars with a maximum of twelve enamel folds an origin at Südelefanten is considered likely. Its early form is now often addressed as Mammuthus rumanus. A settlement of Crete by the Südelefanten some three million years ago, which reached the island floating, therefore would be quite possible, and would then passed through the separation from mainland populations for dwarfing and training of the shape of the Crete - dwarf mammoths. When this became extinct, is currently unknown.