Palaeoloxodon recki

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Palaeoloxodon recki
Temporal range: Late Pliocene–Middle Pleistocene
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Size comparison of a 40 year old adult male Palaeoloxodon recki atavus from Koobi Fora
Life restoration by Mauricio Antón
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Family: Elephantidae
Genus: †Palaeoloxodon
Species:
†P. recki
Binomial name
†Palaeoloxodon recki
(Dietrich, 1894)
Synonyms

Elephas recki Dietrich, 1894

Palaeoloxodon recki, often known by the synonym Elephas recki is an

Middle Pleistocene. During most of its existence, the species (in its broad sense) represented the dominant elephant species in East Africa.[1] The species is divided into five roughly chronologically successive subspecies. While the type and latest subspecies P. recki recki as well as the preceding P. recki ileretensis are widely accepted to be closely related to Eurasian Palaeoloxodon
, the relationships of the other, chronologically earlier subspecies to P. recki recki and P. recki ileretensis are uncertain, with it being suggested they are unrelated and should be elevated to separate species.

Taxonomy

The species was initially named from specimens found at Bed IV in

Omo Valley in Ethiopia, and suggested that they were distinctive enough that they warranted being placed as the distinct species E. recki. The two deposits are not contemporaneous and the specimens from each locality are morphologically distinctive from each other, which has led to confusion about which locality represents the "typical" morphology of the species.[2] The placement of Elepas recki in the genus Elephas was contested as early as 1942, when in a publication by Douglas Gordon MacInnes and Henry Fairfield Osborn's posthumous monograph on fossil proboscideans it was suggested that Elephas recki should instead be placed in Palaeoloxodon, though many later authors continued to place the species in the genus Elephas, treating Palaeoloxodon as a subgenus of Elephas.[3]

Michel Beden's publications during the 1980s on Elephas recki primarily focusing on molar morphology[4][5][6] identified five successive subspecies, from oldest to youngest with ages according to Sanders (2023)[3]:

  • E. r. brumpti Beden, 1980 Early Pliocene-~3.2 million years ago (mya)
  • E. r. shungurensis Beden, 1980 ~3.2-2.3 mya
  • E. r. atavus Arambourg, 1947 ~2.3-1.8 mya
  • E. r. ileretensis Beden, 1987 ~1.8-1.4/1.6 mya
  • E. r. recki (Dietrich, 1916) 1.6/1.4 mya-late Middle Pleistocene

For decades after Beden's publications, his view of "Elephas recki" as a succession of subspecies was accepted as orthodoxy. However, Beden's views of Elephas recki evolution were challenged by the work of Nancy Todd published in 2001 and 2005.

cladistic analysis, as would be expected if they formed a single species, with E. r. brumpti E. r. shungurensis and E. r. atavus being placed separately from E. r. ileretensis and E. r. recki, and that the supposed subspecies substantially chronologically overlapped, though later work suggested that this chronological overlap was likely overstated.[3]

A 2020 PhD thesis by Steven Zhang, focusing primarily on skull morphology again challenged the monophyly of Elephas recki as a whole, finding that while E. r. ileretensis and E. recki recki has a close relationship with Eurasian Palaeoloxodon. which genetic data shows is closely related to African elephants (

Loxodonta), the other named E. recki subspecies were likely unrelated, and more closely related to true members of the genus Elephas (which contains the living Asian elephant). Zhang suggested that E. r. brumpti was synonymous with "Elephas" planifrons, primarily known from the Late Pliocene-Early Pleistocene of the Indian subcontinent, and that this species should be placed into Phanagoroloxodon, while E. r. atavus should be elevated to full species status as a true member of the genus Elephas. However, while Sanders (2023) accepted that E. r. brumpti was unlikely to be closely related to E. recki recki, he rejected the synonymity of E. r. brumpti with "Elephas" planifrons (though he suggested that the two may be sister species), and questioned their placement in Phanagoroloxodon, while he considered the relationship of E. r. atavus to E. recki recki to be uncertain.[3]

Outside its core East African distribution. It has also been suggested that material from

Gesher Bnot Ya'akov (otherwise attributed to P. antiquus) in northern Israel, the Middle Pleistocene (c. 500,000 years ago) Ti's al Ghadah site in northern Saudi Arabia, and the late Middle Pleistocene Shishan Marsh site in Jordan, belongs to P. recki recki.[7][8][9][3]

Description

Members of the species were larger than any living elephant. A large mostly complete male specimen of P. recki atavus

hypsodonty).[12]

Ecology

All named subspecies of P/E. recki, regardless of true evolutionary relationships, are thought to have been dedicated grazers, with the molar teeth of later subspecies showing greater adaption to grazing than earlier subspecies.[1]

Evolutionary history

Following the emergence of P. recki in Africa, at the end of the Early Pleistocene, around 800,000 years ago, a population of P. recki recki migrated out of Africa, giving rise to the Eurasian radiation of Palaeoloxodon.

Middle Pleistocene to Late Pleistocene age. Following the extinction of P. iolensis it was replaced by the modern African bush elephant (Loxodonta africana).[1]

Relationship with humans

At several sites across Africa, remains of P. recki have been found associated with stone tools. In some cases like Olduvai FLK, these are likely coincidental, but in others which bears cut marks, these likely represent evidence of butchery by

handaxe and other bifaced tools, and displays cut marks and fracture marks indicative of butchery, though the fracturing of the skull, which has been suggested to be the result of an attempt to extract the brain, may alternatively be the result of postmortem trampling.[14]

Gallery

References

  1. ^
    S2CID 198190671
    .
  2. ^
    doi:10.1016/j.quaint.2004.04.015
    .
  3. ^
    ISBN 978-1-315-11891-8
    .
  4. ^ Beden, M. 1980. Elephas recki Dietrich, 1915 (Proboscidea, Elephantidae). Èvolution au cours du Plio-Pléistocène en Afrique orientale. Geobios 13(6): 891-901. Lyon.
  5. ^ Beden, M. 1983. Family Elephantidae. In J. M. Harris (ed.), Koobi Fora Research Project. Vol. 2. The fossil Ungulates: Proboscidea, Perissodactyla, and Suidae: 40-129. Oxford: Clarendon Press.
  6. ^ Beden, M. 1987. Les faunes Plio-Pléistocène de la basse vallée de l’Omo (Éthiopie), Vol. 2: Les Eléphantidés (Mammalia-Proboscidea) (directed by Y. Coppens and F. C. Howell): 1-162. Cahiers de Paléontologie-Travaux de Paléontologie est-africaine. Centre National de la Recherche Scientifique (CNRS). Paris.
  7. ^
    S2CID 213676377
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  8. hdl:10072/142575
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  9. ISSN 0033-5894
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  10. doi:10.4202/app.00136.2014
    .
  11. ISSN 0891-2963
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  12. S2CID 883007
    .
  13. ISBN 978-1-78570-965-4
    , retrieved 2020-04-14
  14. ISSN 2571-550X
    .
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