Mammuthus lamarmorai

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Mammuthus lamarmorai
Temporal occurrence
Late Middle Pleistocene to Young Pleistocene
450,000 to 40,000 years
Locations
Systematics
Elephantimorpha
Elephantida
Elephants (Elephantidae)
Elephantinae
Mammoths ( Mammuthus )
Mammuthus lamarmorai
Scientific name
Mammuthus lamarmorai
( Major , 1883)

Mammuthus lamarmorai is a representative of the genus of mammoths ( Mammuthus ), which is endemic in the late Middle and Upper Pleistocene pre approximately 450,000 to possibly 40,000 years ago on the island of Sardinia lived. He reached a shoulder height of only 1.4 m and weighed about 750 kg. This dwarf mammoth has mainly been found in fine-grain deposits in the western part of the island.

features

There are several fossil remains of Mammuthus lamarmorai , which include skull and tooth finds as well as remains of the body skeleton; however, no complete skeleton is known to date. It is a dwarf form of the mammoth. Of the few known molars , only one represents a rearmost tooth. It is 13 cm long and 6.9 cm wide and has at least eleven enamel folds on the chewing surface. A humerus reaches a length of 46 cm. The few tusk fragments found show only a small diameter of a maximum of 3.5 cm. The length of the thigh bone suggests a shoulder height of 1.4 to 1.5 m. The weight of this dwarf mammoth should not have been more than 750 kg. The only small size of Mammuthus lamarmorai goes back to an island dwarfing that occurred when the originally large ancestors reached Sardinia and reduced their body size due to a smaller food supply and a lack of potential predators.

Finds

Most of the finds of Mammuthus lamarmorai were discovered on the west coast or in the western part of the island of Sardinia and consist mainly of individual finds, but also related skeletal elements. The most important fossils come from Funtana Morimenta, a quarry south-southwest of Gonnesa in the valley of the Rio Morimenta, where they were discovered at the end of the 19th century. These fossil embedded in the Funtana-Morimenta formation , one from aeolian sedimentary rocks constructed formation located below one of conglomerates dominated rock unit ( Tyrrenic conglomerate is located). This rock formation is widespread over the west coast of Sardinia and is generally attributed to the last warm period , which in the northern Alpine region is called the Eem warm period (126,000 to 115,000 years ago). The finds mainly include elements of the spine and the musculoskeletal system, including a complete foot , an almost complete hand , humerus and spoke , but also remains of tusks . All finds most likely belong to a single individual. Further finds are known from San Giovanni di Sinis near Oristano , where a molar was found in sediments also deposited before the Eem warm period, as well as another molar from Campu Giavesu near Sassari , which is, however, significantly larger. Finds from the Young Pleistocene , which include several teeth, are mainly known from Tramariglio near the city of Alghero and also came from sediments deposited by wind , but above the Tyrrhenian conglomerate.

Systematics

Mammuthus lamarmorai is a representative of the mammoths , which are closely related to the Asian elephant ( Elephas maximus ). The occurrence of this mammoth form as early as the late Middle Pleistocene makes a descent from the classic woolly mammoth ( Mammuthus primigenius ) rather improbable, as this only appeared later in Europe. At that time only the steppe mammoth ( Mammuthus trogontherii ) lived on the continent. The fact that he was the ancestor of Mammuthus lamarmorai can also be assumed by the shape of the molars with their only eleven, relatively thin enamel folds, which therefore appear significantly more archaic than those of the woolly mammoth . In addition to the Cretan dwarf mammoth ( Mammthus creticus ), Mammthus lamarmorai is the only known dwarf mammoth form on the islands of the Mediterranean that were otherwise inhabited by short members of the genus Palaeoloxodon .

The first description was in 1883 by Charles Immanuel Forsyth Major , who used the name Elephas lamarmorae . He did not publish any images, but saw a clear connection to the southern elephant ( Mammuthus meridionalis ), which he in turn called Elephas meridionalis , due to similarities . The remains came from the Funtana Morimenta quarry and are now kept in the Natural History Museum in Basel , where Major personally brought them. Due to new tooth finds from the middle of the 20th century, the close connection to the mammoths became clear, which is why the name Mammuthus lamarmorae became established . Due to an adjustment to the International Rules for Zoological Nomenclature , a change was made in 2012 to Mammuthus lamarmorai , the species name that is valid today. The species name lamarmorai honors the Sardinian general and naturalist Alberto La Marmora (1789–1863), who had already investigated the Funtana Morimenta outcrop in 1858.

Tribal history

The origin of Mammuthus lamarmorai is still relatively unclear - the earliest finds come from the late period of the Middle Pleistocene , as indicated by their association with the giant deer Praemegaceros cazioti , and are therefore around 450,000 years old. A settlement of Sardinia by the steppe mammoth should therefore have taken place in the transition from the Old to the Middle Pleistocene or in the early Middle Pleistocene. This probably happened during one of the Pleistocene glacial periods , in which the global sea level was significantly lower due to the water bound in the continental ice sheets and the animals could reach the island by swimming. It is unclear whether individual mammoth populations only reached Sardinia once; the slightly larger tooth of Campu Giavesu may also make several waves of migration appear possible, as has also been proven in the case of finds of dwarfed forms of the genus Elephas from the Mediterranean islands of Sicily and Malta .

Individual evidence

  1. ^ R. Melis, Maria Rita Palombo and Margherita Mussi : Mammuthus lamarmorae (Major, 1883) remains in the pre-Tyrrhenian deposits of San Giovanni in Sinis (Western Sardinia, Italy). In: G. Cavarretta, P. Gioia, M. Mussi and Maria Rita Palombo (eds.): The World of Elephants - International Congress. Consiglio Nazionale delle Ricerche. Rome, 2001, pp. 481-485
  2. ^ A b c Maria Rita Palombo: Elephants in miniature. In: Harald Meller (Hrsg.): Elefantenreich - Eine Fossilwelt in Europa. Halle / Saale, 2010, pp. 275-295 ISBN 978-3-939414-48-3
  3. ^ A b c d Maria Rita Palombo, MP Ferretti, GL Pillola and L. Chiappini: A reappraisal of the dwarfed mammoth Mammuthus lamarmorai (Major, 1883) from Gonnesa (south-western Sardinia, Italy). Quaternary International 255, 2012, pp. 158-170
  4. ↑ Lucia Caloi, Tassos Kotsakis, Maria R. Palombo and Carmelo Petronio: The Pleistocene dwarf elephants from Mediterranean islands. In: Jeheskel Shoshani and Pascal Tassy (eds.): The Proboscidea. Evolution and palaeoecology of the Elephants and their relatives. Oxford, New York, Tokyo, 1996, pp. 234-239
  5. ^ Maria Rita Palombo: Endemic elephants of the Mediterranean Islands: knowledge, problems and perspectives. In: G. Cavarretta, P. Gioia, Margherita Mussi and Maria Rita Palombo (eds.): The World of Elephants - International Congress. Consiglio Nazionale delle Ricerche. Rome, 2001, pp. 486-491