Crete dwarf mammoth

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Crete dwarf mammoth
Crete pygmy mammoth (Mammuthus creticus)

Crete pygmy mammoth ( Mammuthus creticus )

Temporal occurrence
late Old Pleistocene to early Middle Pleistocene
approx. 800,000 years
Locations
  • Crete
Systematics
Elephantimorpha
Elephantida
Elephants (Elephantidae)
Elephantinae
Mammoths ( Mammuthus )
Crete dwarf mammoth
Scientific name
Mammuthus creticus
( Bate , 1907)

The Crete pygmy mammoth ( Mammuthus creticus ) lived at the transition from the older to the middle Pleistocene before approximately 740,000 years on Crete and represents the smallest known today Mammutart represents. Skeletal remains are rare, the size and weight calculations are based on molar teeth and bones .

features

Finds of the Cretan dwarf mammoth include largely fragmented bone material. Skull fossils have not been handed down, the molars are especially known . In adult individuals, these are about 13.9 to 14.5 cm long, 3.3 to 3.7 cm wide and have 10 to 12 enamel folds on the chewing surface. Also suitable postcranial skeletal elements such as ribs, vertebrae and long bones before. A humerus of an adult animal has a length of 33 cm. Mainly because of this find, a shoulder height of about 1.13 m and a body weight of about 310 kg are calculated for the Crete dwarf mammoth . This makes the Crete dwarf mammoth one of the smallest known representatives of the elephants (Elephantidae).

Size comparisons

The finds from Crete show a typical island dwarfing , which occurs when populations of originally large animals are separated from the mainland area and with the associated limited food supply, but also a lack of predators. This has been proven several times in the line of the elephants (Elephantidae). With the specified size values, the Cretan dwarf mammoth is the smallest known mammoth species in the world. Among the remaining elephants, only the Sicilian pygmy elephant ( Palaeoloxodon falconeri ) and Palaeoloxodon cypriotes , both of which come from the Young Pleistocene , became smaller. The Sicilian dwarf elephant was found in Malta and Sicily and reached a maximum height of 1 m, with a weight of 170 to 240 kg, whereas Palaeoloxodon cypriotes weighed about 250 kg. Both are descendants of the European forest elephant ( Palaeoloxodon antiquus ), which was up to 4.2 m tall and weighed around 11 t.

Among the mammoths, the Middle to Young Pleistocene species Mammuthus lamarmorai , which is documented in Sardinia, is the next larger form with a shoulder height of 1.5 m and a weight of 800 kg. The dwarfed woolly mammoths ( Mammuthus primigenius ) from Wrangel Island in the Arctic Ocean , which date back to the mid- Holocene and are among the youngest mammoth finds ever, had a shoulder height of 1.8 m and a weight of a good 2 t. The woolly mammoths from the Pribilof Islands off the coast of Alaska , which also survived into the Middle Holocene and were only slightly dwarfed, were even larger . The dwarf mammoths of the species Mammuthus exilis of the Channel Islands off the coast of California , which may descend from the prairie mammoth ( Mammuthus columbi ) and also have a Young Pleistocene age, varied extremely in their size, so that the shoulder height is between 1.2 and 1.8 m.

A fully grown "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 southern elephant ( Mammuthus meridionalis ) and the prairie mammoth had a shoulder height of 4 m and weighed a good 10 t, the largest mammoth and at the same time the largest trunk animal known today was the steppe mammoth ( Mammuthus trogontherii ), which up to 4 , 5 m high (excluding soft tissue) and an estimated weight of up to 15 t.

Finds

The majority of the finds of the Cretan dwarf mammoth come from Cape Maleka ( ⊙ ) on the Akrotiri peninsula in northwest Crete . These mostly include finds of molar teeth, but also ribs and long bones. The first finds, mainly molars, came to light here as early as 1905 and were used for the first description of the species. Further finds date from 1973 and were made by the Dutch paleontologist Paul Sondaar . The latest finds so far were made in 2011, including molars and a humerus . Due to the additional finds with the rodent Kritimys kiridus , an age in the transition from the Old to the Middle Pleistocene was assumed for the finds, which was generally given as 800,000 years. Based on geophysical studies, it is now assumed to be 738,000 years old.

Systematics

Panel from the first description of Mammuthus creticus in 1907 by Dorothea Bate with a representation of the lectotype

In her first analysis, published in 1907, based on some finds that included nine molars, some tusk fragments and a broken vertebra, Dorothea Bate referred to the finds from Cape Maleka as Elephas creticus . A posterior molar is considered a lectotype of the species (copy number NHM M 9381). The Crete dwarf mammoth was mostly referred to as Elephas (Palaeoloxodon) creticus due to its suspected relationship to the European forest elephant and its assignment to Elephas or Palaeoloxodon . The occurrence of two other Pleistocene elephant species on Crete, which were assigned to the species Palaeoloxodon creutzburgi and Palaeoloxodon priscus , but were much younger and above all larger and are mostly integrated into the European forest elephant, also caused irritation .

Due to the age of the finds and the earliest occurrence of the European forest elephant in Europe, doubts arose about such a relationship. As early as 1996, the Dutch paleontologist Dick Mol pointed out a possible relationship to the mammoths. However, as early as 1907 in her first description, Bate recognized similarities to the mammoths, especially the southern elephant, which she called Elephas meridionalis . Molecular genetic studies from 2006 then provided further evidence of ancestry from Mammuthus . However, this study was later heavily criticized because of the old age of the findings, the small number of DNA base pairs examined (43 bp) and methodological errors.

New analyzes from 2011 on newly found material confirmed the allocation to the mammoths, whereby the molars were used in particular. In Mammuthus these are wider in relation to length than in Palaeoloxodon . In addition, the molars of mammoths also have much narrower and often continuous enamel folds with clearly parallel edges, in contrast to those of the representatives of Palaeoloxodon , whose enamel folds are more subdivided and have more bulging edges in the middle.

Tribal history

Theoretically, both the southern elephant and the steppe mammoth come into question for the origin of the Crete dwarf mammoth. The former developed more than three, the latter one and a half million years ago. Due to the structure of the molar teeth with a maximum of twelve enamel folds, an origin in the southern elephant is considered more likely. Its early form is now often referred to as Mammuthus rumanus . Settlement of Crete by the southern elephant around three million years ago, which reached the island by swimming, would therefore have been entirely possible and would then have led to the dwarfing and formation of the shape of the Cretan dwarf mammoth through the separation from the mainland populations. When this died out is still unclear.

Individual evidence

  1. ↑ a b c d Victoria L. Herridge and Adrian M. Lister: Extreme insular dwarfism evolved in a mammoth. Proceedings of the Royal Society series B 2012 doi: 10.1098 / rspb.2012.0671 .
  2. ^ Maria Rita Palombo, Ebru Albayrak and Federica Marano: The straight-tusked Elephants from Neumark-Nord. A glance into a lost world. In: Harald Meller (Hrsg.): Elefantenreich - Eine Fossilwelt in Europa. Halle / Saale, 2010, pp. 219-25 ISBN 978-3-939414-48-3
  3. ^ A b 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
  4. ^ A b Adrian M. Lister: Mammoths in miniature. Nature 362, 1993, pp. 288-289
  5. ↑ JM Enk, DR Yesner, KJ Crossen, DW Veltre and DH O'Rourke: Phylogeographic Analysis of the mid-Holocene Mammoth from Qagnax Cave, St. Paul Island, Alaska. Palaeogeography, Palaeoclimatology, Palaeoecology 273 (1-2), 2009, pp. 184-190
  6. ^ V. Louise Roth: Pleistocene dwarf elephants from the California 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. 249-253
  7. ^ Adrian Lister and Paul Bahn: Mammuts - The Giants of the Ice Age . Sigmaringen, 1997 (pp. 24 and 29) ISBN 3-7995-9050-1
  8. ↑ Jehezekel Shoshani: Understanding proboscidean evolution: a formidable task. Tree 13, 1998, pp. 480-487
  9. ^ Mikael Fortelius and John Kappelmann The largest land mammal ever imagined. Zoological Journal of the Linnean Society 107, 1993, pp. 85-101
  10. ↑ Alexandra van der Geer, George Lyras, John de Vos and Michael Dermitzakis: Evolution of island mammals. Adaptation and extinction of placental mammals on islands. Oxford 2010 (here pp. 43–61), ISBN 978-1-4051-9009-1 , ( [1] )
  11. ^ Maria Rita Palombo: Endemic elephants of the Mediterranean Islands: knowledge, problems and perspectives. In: G. Cavarretta et al. (Eds.): The World of Elephants - International Congress. Consiglio Nazionale delle Ricerche. Rome, 2001, pp. 486-491
  12. ↑ a b Nikos Poulakakis, Aris Parmakelis, Petros Lymberakis, Moysis Mylonas, Eleftherios Zouros, David S. Reese, Scott Glaberman and Adalgisa Caccone: Ancient DNA forces reconsideration of evolutionary history of Mediterranean pygmy elephantids. Biological Letters (The Royal Society) 2006, pp. 1-4
  13. ^ A b Dorothea MA Bate: On Elephant Remains from Crete, with Description of Elephas creticus, sp. n. Proceedings of the Zoological Society of London 77 (2), 1907, pp. 238-250
  14. ↑ 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
  15. ^ A b C.S. Doukas, A. Athanassiou: Review of the Pliocene and Pleistocene Proboscidea (Mammalia) from Greece . In: Reumer, JWF, De Vos, J. & Mol, D. (Eds.): Advances in Mammoth Research (Proceedings of the Second International Mammoth Conference, Rotterdam, May 16-20 1999) (=  Deinsea 9 ). May 24, 2003, ISSN  0923-9308 , p. 97–110 ( Online [PDF; 1.1 MB ; accessed on May 22, 2012]).
  16. ↑ Ludovic Orlando, Marie Pagés, Sébastien Calvignac, Sandrine Hughes and Catherine Hänni: Does the 43bp sequence from an 800000 year old Cretan dwarf elephantid really rewrite the textbook on mammoths ?. Biological Letters 3 (1), 2007, pp. 57-59
  17. ↑ Victoria L. Herridge and Adrian M. Lister: Extreme insular dwarfism evolved in a mammoth: Supplementary Information. Proceedings of the Royal Society series B 2012 doi: 10.1098 / rspb.2012.0671 .
  18. ^ Adrian M. Lister and Hans van Essen: The earliest mammoth of Europe. 18th International Senckenberg Conference in Weimar 2004 Abstracts ( PDF )

Web links

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