Palaeoloxodon namadicus: Difference between revisions

Some authorities historically regarded ''P. namadicus'' and the European [[straight-tusked elephant]] (''P. antiquus'') as the same species due to their similar skull morphology.<ref>{{cite journal |last1=Ferretti |first1=M.P. |date=May 2008 |title=The dwarf elephant Palaeoloxodon mnaidriensis from Puntali Cave, Carini (Sicily; late Middle Pleistocene): Anatomy, systematics and phylogenetic relationships |journal=Quaternary International |volume=182 |issue=1 |pages=90–108 |bibcode=2008QuInt.182...90F |doi=10.1016/j.quaint.2007.11.003}}</ref> ''P. namadicus'' shares similarities to other species of ''[[Palaeoloxodon]],'' which includes a large crest (the parieto-occipital crest) at the top of the skull that anchored the [[splenius muscles]] used to support the head, which is more developed in males than in females. Later research suggested that ''P. namadicus'' can be distinguished from ''P. antiquus'' by its less robust (more elongate) limb bones and more stout cranium (including a better developed parieto-occipital crest), and the presence of a depression in the infraorbital region behind the eyesocket not found in ''P. antiquus''.<ref name=":0">{{Cite journal |last1=Larramendi |first1=Asier |last2=Zhang |first2=Hanwen |last3=Palombo |first3=Maria Rita |last4=Ferretti |first4=Marco P. |date=February 2020 |title=The evolution of Palaeoloxodon skull structure: Disentangling phylogenetic, sexually dimorphic, ontogenetic, and allometric morphological signals |journal=Quaternary Science Reviews |language=en |volume=229 |pages=106090 |bibcode=2020QSRv..22906090L |doi=10.1016/j.quascirev.2019.106090 |s2cid=213676377}}</ref> Like other large ''Palaeoloxodon'' species, the tusks were likely proportionally large, though no complete tusks are known. One partial tusk was estimated to be {{Convert|3.66|m|ft}} long and over {{Convert|120|kg|lb}} in weight when complete, larger than the largest recorded [[African bush elephant]] tusk.<ref>{{Cite journal |last=Larramendi |first=Asier |date=2023-12-10 |title=Estimating tusk masses in proboscideans: a comprehensive analysis and predictive model |url=https://www.tandfonline.com/doi/full/10.1080/08912963.2023.2286272 |journal=Historical Biology |language=en |pages=1–14 |doi=10.1080/08912963.2023.2286272 |issn=0891-2963}}</ref>

[[File:Palaeoloxodon namadicus-bpk.jpg|thumb|Life restoration]]Fossils of ''Palaeoloxodon namadicus'' are known from the northern and central Indian subcontinent, including the [[Narmada River|Narmada]] and [[Godavari River|Godavari]] valleys, and the [[Indo-Gangetic Plain]].<ref>{{Cite journal |last=Ghosh |first=Rupa |last2=Sehgal |first2=R. K. |last3=Srivastava |first3=Pradeep |last4=Shukla |first4=U. K. |last5=Nanda |first5=A. C. |last6=Singh |first6=D. S. |date=November 2016 |title=Discovery of Elephas cf. namadicus from the late Pleistocene strata of Marginal Ganga Plain |url=http://link.springer.com/10.1007/s12594-016-0521-7 |journal=Journal of the Geological Society of India |language=en |volume=88 |issue=5 |pages=559–568 |doi=10.1007/s12594-016-0521-7 |issn=0016-7622}}</ref> Based on [[stable isotope ratio]]s of carbon and oxygen and the morphology of their teeth, it is suggested that ''P. namadicus'' tended towardshad a [[Grazing (behaviour)|grazing]]-mixed feeding diet,<ref name=":4" /><ref name=":5">{{Cite journal |last1=Maurya |first1=Sakshi |last2=Ghosh |first2=Rupa |last3=Sehgal |first3=Ramesh Kumar |last4=Srivastava |first4=Pradeep |last5=Shukla |first5=Uma Kant |last6=Singh |first6=Abhishek Pratap |last7=Sarangi |first7=Shushanta |date=September 2022 |title=Stable Isotopic studies of the herbivorous mammals from the Marginal Ganga Plain, India: implication for the palaeo-environmental reconstruction |url=https://onlinelibrary.wiley.com/doi/10.1002/gj.4522 |journal=Geological Journal |language=en |volume=57 |issue=9 |pages=3935–3948 |doi=10.1002/gj.4522 |issn=0072-1050}}</ref> with a specimen found on the banks of the [[Dhasan River]] suggested to have primarily consumed [[C4 carbon fixation|C₄]] grasses.<ref name=":5" /> The species is suggested to have primarily inhabited open [[grassland]] habitats.<ref name=":4" /><ref name=":5" /> Its arrival on the subcontinent coincides with a shift in the diet of contemporaneous ''[[Elephas hysudricus]]'' (the ancestor of the living [[Asian elephant]]) from a grazing diet towards [[Browsing (herbivory)|browsing]]-mixed feeding, possibly as a result of [[niche partitioning]].<ref name=":4">{{Cite journal |last1=Patnaik |first1=Rajeev |last2=Singh |first2=Ningthoujam Premjit |last3=Paul |first3=Debajyoti |last4=Sukumar |first4=Raman |date=2019-11-15 |title=Dietary and habitat shifts in relation to climate of Neogene-Quaternary proboscideans and associated mammals of the Indian subcontinent |url=https://www.sciencedirect.com/science/article/pii/S027737911930263X |journal=Quaternary Science Reviews |language=en |volume=224 |pages=105968 |doi=10.1016/j.quascirev.2019.105968 |bibcode=2019QSRv..22405968P |issn=0277-3791 |s2cid=210307849}}</ref>

''P. namadicus'' is primarily known from the Indian subcontinent.<ref name=":0" /> Remains attributed to ''P. namadicus'' have also been reported across Southeast Asia (including Malaysia, Myanmar, Laos, and Vietnam, and the island of [[Sulawesi]] in Indonesia) and as well as China.<ref>{{Cite journal |last1=Louys |first1=Julien |last2=Curnoe |first2=Darren |last3=Tong |first3=Haowen |date=January 2007 |title=Characteristics of Pleistocene megafauna extinctions in Southeast Asia |url=https://linkinghub.elsevier.com/retrieve/pii/S0031018206004032 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=243 |issue=1–2 |pages=152–173 |doi=10.1016/j.palaeo.2006.07.011|bibcode=2007PPP...243..152L }}</ref><ref>{{Cite journal |last1=Geer |first1=Alexandra A. E. |last2=Bergh |first2=Gerrit D. |last3=Lyras |first3=George A. |last4=Prasetyo |first4=Unggul W. |last5=Due |first5=Rokus Awe |last6=Setiyabudi |first6=Erick |last7=Drinia |first7=Hara |date=August 2016 |title=The effect of area and isolation on insular dwarf proboscideans |url=https://onlinelibrary.wiley.com/doi/10.1111/jbi.12743 |journal=Journal of Biogeography |language=en |volume=43 |issue=8 |pages=1656–1666 |doi=10.1111/jbi.12743 |bibcode=2016JBiog..43.1656V |issn=0305-0270 |s2cid=87958022}}</ref> However, the status of Chinese ''Palaeoloxodon'' is unresolved, with other authors considering the remains to belong to ''[[P. naumanni]]'' (otherwise known from Japan) or the separate species ''[[Palaeoloxodon huaihoensis|P. huaihoensis]]''. The postcranial remains of ''Palaeoloxodon'' from China are substantially more robust than Indian ''P. namadicus'' and in many respects are more similar to those of ''P. antiquus'' and their skulls lack the infraorbital depression characteristic of Indian ''P. namadicus'' specimens'','' making their referral to ''P. namadicus'' questionable.<ref name=":0" />

The oldest specimens of ''P. namadicus'' in India are thought to be over 700,000 years old, dating to the early Middle Pleistocene,<ref name=":0" /> having evolved, like other Eurasian ''Palaeoloxodon'' species from a migration of a population of ''[[Palaeoloxodon recki]]'' out of Africa.<ref>{{Citation |last=Lister |first=Adrian M. |title=Ecological Interactions of Elephantids in Pleistocene Eurasia |date=2004 |url=https://www.researchgate.net/publication/264788794 |work=Human Paleoecology in the Levantine Corridor |pages=53–60 |access-date=2020-04-14 |publisher=Oxbow Books |isbn=978-1-78570-965-4}}</ref> ''Palaeoloxodon namadicus'' is thought to have become [[extinct]] during the [[Late Pleistocene]], making it one of four [[megafauna]] species native to the Indian subcontinent suggested to have become extinct during the Late Pleistocene, alongside fellow [[proboscidea]]n ''[[Stegodon|Stegodon namadicus]]'', the equine ''[[Equus namadicus]]'', and the hippopotamus ''[[Hexaprotodon]],'' along with the local extinction of [[Ostrich|ostriches]], as part of a [[Late Pleistocene extinctions|global wave of megafaunal extinctions]] during the Late Pleistocene.<ref name=":2">{{Cite journal |last1=Jukar |first1=A.M. |last2=Lyons |first2=S.K. |last3=Wagner |first3=P.J. |last4=Uhen |first4=M.D. |date=January 2021 |title=Late Quaternary extinctions in the Indian Subcontinent |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=562 |pages=110137 |doi=10.1016/j.palaeo.2020.110137 |s2cid=228877664 |doi-access=free|bibcode=2021PPP...56210137J }}</ref><ref name=":1">{{Cite journal |last1=Turvey |first1=Samuel T. |last2=Sathe |first2=Vijay |last3=Crees |first3=Jennifer J. |last4=Jukar |first4=Advait M. |last5=Chakraborty |first5=Prateek |last6=Lister |first6=Adrian M. |date=January 2021 |title=Late Quaternary megafaunal extinctions in India: How much do we know? |url=https://linkinghub.elsevier.com/retrieve/pii/S0277379120307022 |journal=Quaternary Science Reviews |language=en |volume=252 |pages=106740 |doi=10.1016/j.quascirev.2020.106740 |bibcode=2021QSRv..25206740T |s2cid=234265221}}</ref> The exact time of extinction of these taxa is unclear due to the uncertantiesuncertainties regarding dating, but indirect dating from several sites suggests that ''P. namadicus'' became extinct within the last 50,000 years, with some records possibly as late as 25,000 years ago, implying that ''P. namadicus'' overlapped with modern humans in the region.<ref name=":1" /><ref name=":2" />

There is little direct evidence for human interaction with ''P. namadicus.'' One of the only Middle Pleistocene sites for which there is evidence for human interaction with elephants in the Indian subcontinent is from Galander, near [[Pampore]] in the [[Kashmir Valley|Kashmir valley]], where an individual of ''Palaeoloxodon'' indeterminate to species, which has a weak parietal-occpitialoccipital crest much different from individuals typically attributed to ''P. namadicus,'' was found to have its bones delibrately fractured by humans using stone tools, possibly for the purposes of butchery. At the site [[Mousterian|Mousterian/Mode III]]-grade tools made of basalt were found, suggesting a late Middle Pleistocene age (approximately 400-130,000 years ago) for the site. There is no evidence that the elephant was hunted, and it may have been scavenged after dying of natural causes.<ref>{{Cite journal |lastlast1=Bhat |firstfirst1=Ghulam M. |last2=Ashton |first2=Nick |last3=Parfitt |first3=Simon |last4=Jukar |first4=Advait |last5=Dickinson |first5=Marc R. |last6=Thusu |first6=Bindra |last7=Craig |first7=Jonathan |date=October 2024-10 |title=Human exploitation of a straight-tusked elephant (Palaeoloxodon) in Middle Pleistocene deposits at Pampore, Kashmir, India |url=https://linkinghub.elsevier.com/retrieve/pii/S0277379124003950 |journal=Quaternary Science Reviews |language=en |volume=342 |pages=108894 |doi=10.1016/j.quascirev.2024.108894|doi-access=free }}</ref>