Palaeoloxodon recki

Palaeoloxodon recki is an extinct species of elephant native to Africa from the late Pliocene to Middle Pleistocene. During most of its existence, it represented the dominant elephant species in East Africa. Its descendant taxon or last evolutionary stage, Palaeoloxodon iolensis, is known from remains found across Africa of late Middle Pleistocene to Late Pleistocene age. Both P. recki and P. iolensis are thought to have been grazers, based on isotopic and morphological evidence. Following the extinction of P. iolensis it was replaced by the modern African bush elephant (Loxodonta africana).[1] At the end of the Early Pleistocene, a population of P. recki migrated out of Africa, giving rise to the Eurasian radiation of Palaeoloxodon.[2]

Palaeoloxodon recki
Temporal range:
Size comparsion of a 40 year old adult male from Koobi Fora
Life restoration by Mauricio Antón
Scientific classification edit
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Family: Elephantidae
Genus: †Palaeoloxodon
Species:
†P. recki
Binomial name
†Palaeoloxodon recki
(Dietrich, 1894)
Synonyms

Elephas recki

A large male specimen of P. recki from Koobi Fora, Kenya, suggested to have been approximately 40 years old when it died, was estimated in a 2016 study to have measured 4.27 metres (14.0 ft) tall and weighed 12.3 tonnes (12.1 long tons; 13.6 short tons).[3]

Taxonomy

The species was initially named from specimens found at Bed IV in Olduvai Gorge, Tanzania by Wilhelm Otto Dietrich in 1915, originally as a subspecies of the European straight-tusked elephant, what is now called Palaeoloxodon antiquus, as Elephas antiquus recki. Arambourg in 1942 described additional specimens of the species from 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.[4] M. Beden [5][6][7] identified five subspecies of Palaeoloxodon recki, from oldest to youngest:

  • P. r. brumpti Beden, 1980
  • P. r. shungurensis Beden, 1980
  • P. r. atavus Arambourg, 1947
  • P. r. ileretensis Beden, 1987
  • P. r. recki (Dietrich, 1916)

New research indicates that the ranges for all five subspecies overlap, and that they are not separated in time as previously proposed. The research also found a wide range of morphological variation, both between the supposed subspecies and between different specimens previously identified as belonging to the same subspecies. The degree of temporal and geographical overlap, along with the morphological variation in P. recki suggests that the relationships between any subspecies are more complicated than previously indicated.[8][4] While previously placed in Elephas, most modern researchers place the species within Palaeoloxodon. Contemporary research has questioned the attribution of many specimens of Palaeoloxodon recki to the species,[9] with a preliminary phylogenetic analysis done in 2018 finding that some remains attributed to P. recki (including the proposed subspecies P. r. brumpti and P. r. atavus) were more closely related to Elephas and Mammuthus, leading to the suggestion that E/P. recki in its broader sense is a wastebasket taxon, though the type material from Olduvai Gorge is clearly assignable to Palaeoloxodon.[10]

References
  1. Manthi, Fredrick Kyalo; Sanders, William J.; Plavcan, J. Michael; Cerling, Thure E.; Brown, Francis H. (September 2020). "Late Middle Pleistocene Elephants from Natodomeri, Kenya and the Disappearance of Elephas (Proboscidea, Mammalia) in Africa". Journal of Mammalian Evolution. 27 (3): 483–495. doi:10.1007/s10914-019-09474-9. ISSN 1064-7554. S2CID 198190671.
  2. Lister, Adrian M. (2004), "Ecological Interactions of Elephantids in Pleistocene Eurasia", Human Paleoecology in the Levantine Corridor, Oxbow Books, pp. 53–60, ISBN 978-1-78570-965-4, retrieved 2020-04-14
  3. Larramendi, A. (2016). "Shoulder height, body mass and shape of proboscideans" (PDF). Acta Palaeontologica Polonica. 61. doi:10.4202/app.00136.2014.
  4. Todd, Nancy E. (January 2005). "Reanalysis of African Elephas recki: implications for time, space and taxonomy". Quaternary International. 126–128: 65–72. doi:10.1016/j.quaint.2004.04.015.
  5. Beden, M. 1980. Elephas recki Dietrich, 1915 (Proboscidea, Elephantidae). Èvolution au cours du Plio-Pléistocène en Afrique orientale]. Geobios 13(6): 891-901. Lyon.
  6. 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.
  7. 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.
  8. Todd, N. E. 2001. African Elephas recki: Time, space and taxonomy. In: Cavarretta, G., P. Gioia, M. Mussi, and M. R. Palombo. The World of Elephants, Proceedings of the 1st International Congress. Consiglio Nazionale delle Ricerche. Rome, Italy. Online pdf Archived 2008-12-16 at the Wayback Machine
  9. Larramendi, Asier; Zhang, Hanwen; Palombo, Maria Rita; Ferretti, Marco P. (February 2020). "The evolution of Palaeoloxodon skull structure: Disentangling phylogenetic, sexually dimorphic, ontogenetic, and allometric morphological signals". Quaternary Science Reviews. 229: 106090. doi:10.1016/j.quascirev.2019.106090.
  10. H. Zhang Elephas recki: the wastebasket? 66th Symposium of Vertebrate Palaeontology and Comparative Anatomy, Manchester. (2018)
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