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→‎Classification: rm a sentence that's hopelessly mixed up, off context and non-cited. In any case the extinct North American Gomphotheres have never had any close relation to the Elephantidae
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[[File:Comparative view of the human and elephant frame, Benjamin Waterhouse Hawkins, 1860.jpg|thumb|"Man, and the elephant" Plate from [[Benjamin Waterhouse Hawkins|Hawkins]] ''A comparative view of the human and animal frame'', 1860]]
[[File:Comparative view of the human and elephant frame, Benjamin Waterhouse Hawkins, 1860.jpg|thumb|"Man, and the elephant" Plate from [[Benjamin Waterhouse Hawkins|Hawkins]] ''A comparative view of the human and animal frame'', 1860]]
{{See also|List of elephant species|Elephants}}
{{See also|List of elephant species|Elephants}}
The family diverged from a common ancestor of the [[Mammutidae]], which includes species termed as [[mastodon]]s. The [[author (zoology)|author]] of Mammutidae also published [[Gomphothere|Gomphotheriidae]], more closely related to Elephantidae, which also includes species previously described as ''[[Mastodon]]''. The classification of proboscideans is unstable and has been frequently revised.
The family diverged from a common ancestor of the [[Mammutidae]], which includes species termed as [[mastodon]]s. The classification of proboscideans is unstable and has been frequently revised.


[[File:Phylogenetic Tree of Elephants and Mammoths 2010.png|thumb|350px|The most accurate [[phylogenetic tree]] of the elephants and mammoths as of 2010]]
[[File:Phylogenetic Tree of Elephants and Mammoths 2010.png|thumb|350px|The most accurate [[phylogenetic tree]] of the elephants and mammoths as of 2010]]

Revision as of 21:19, 3 July 2015

Elephantidae
Temporal range: Pliocene - Holocene, Pliocene–Holocene
A male Asian elephant (Elephas maximus) in the wild at Bandipur National Park in India
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Superfamily: Elephantoidea
Family: Elephantidae
Gray, 1821
Type species
Elephas maximus
Genera

The Elephantidae are a taxonomic family, collectively elephants and mammoths. These are terrestrial large mammals with a trunk and tusks. Most genera and species in the family are extinct. Only two genera, Loxodonta (African elephants) and Elephas (Asiatic elephants), are living.

The family was first described by John Edward Gray in 1821, and later assigned to taxonomic ranks within the order Proboscidea. Elephantidae have also been revised by various authors to include or exclude other extinct proboscidean genera.

Classification

"Man, and the elephant" Plate from Hawkins A comparative view of the human and animal frame, 1860
See also: List of elephant species and Elephants

The family diverged from a common ancestor of the Mammutidae, which includes species termed as mastodons. The classification of proboscideans is unstable and has been frequently revised.

The most accurate phylogenetic tree of the elephants and mammoths as of 2010

The following cladogram shows the placement of the genus Mammuthus among other proboscideans, based on hyoid characteristics:[1]

Elephantidae
Elephantinae
Loxodontini

Loxodonta (African elephants)

Elephantini
Palaeoloxodontina

†Palaeoloxodon

Elephantina

Elephas (Asian elephants)

Mammuthus (Mammoths)

The systematics of the living subspecies and species, the modern elephants, has undergone several revisions. A list of extant Elephantidae, excluding the extinct species of the two genera, includes:[2]

Elephantidae
Elephas (Asiatic)
E. maximus Asian elephant
E. m. maximus Sri Lankan elephant
E. m. borneensis Borneo elephant
E. m. indicus Indian elephant
E. m. sumatranus Sumatran elephant
Loxodonta (African)
L. africana African bush elephant
L. cyclotis African forest elephant
Skeleton of Mammuthus meridionalis at MNHN

Scientific classification of Elephantidae taxa embraces an extensive record of fossil specimens, over millions of years, some of which existed until the end of the last ice age. Some species were extirpated more recently. The discovery of new specimens and proposed cladistics have resulted in systematic revisions of the family and related proboscideans.

Elephantidae are classified informally as the elephant family, or in a paleobiological context as elephants and mammoths. The common name elephant primarily refers to the living taxa, the modern elephants, but may also refer to a variety of extinct species, both within this family and in others (see Elephant (disambiguation)). Other members of Elephantidae, especially members of Mammuthus, are referred to by the common name mammoth.

Evolutionary history

Evolution of elephants from the ancient Eocene (bottom) to the modern day (top)

Although the fossil evidence is very certain, by comparing genes, scientists have discovered evidence that Elephantidae and other proboscideans share a distant ancestry with Sirenia (sea cows) and Hyracoidea (hyraxes).[3] These have been assigned with the demostylians to the clade Paenungulata. In the distant past, members of the hyrax family grew to large sizes, and the common ancestor of all three modern families likely was some kind of amphibious hyracoid.[citation needed] One hypothesis is that these animals spent most of their time underwater, using their trunks like snorkels for breathing.[4][5] Modern elephants have this ability and are known to swim in that manner for up to six hours and 50 km (31 mi).

In the past, a much wider variety of genera and species were found, including the mammoths and stegodons.[6][7]

See also

References

  1. ^ a b Attention: This template ({{cite doi}}) is deprecated. To cite the publication identified by doi:10.1016/j.quaint.2007.02.003, please use {{cite journal}} (if it was published in a bona fide academic journal, otherwise {{cite report}} with |doi=10.1016/j.quaint.2007.02.003 instead.
  2. ^ Shoshani, J. (2005). "Order Proboscidea". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. ISBN 978-0-8018-8221-0. OCLC 62265494.
  3. ^ Ozawa, Tomowo (1997-04-24), "Phylogenetic Position of Mammoth and Steller's Sea Cow Within Tethytheria Demonstrated by Mitochondrial DNA Sequences", Journal of Molecular Evolution, 44 (4): 406–413, doi:10.1007/PL00006160, PMID 9089080 {{citation}}: |access-date= requires |url= (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
  4. ^ West, John B. (2001), "Snorkel breathing in the elephant explains the unique anatomy of its pleura", Respiratory Physiology, 126 (1): 1–8, doi:10.1016/S0034-5687(01)00203-1, PMID 11311306
  5. ^ West, John B.; Fu, Zhenxing; Gaeth, Ann P.; Short, Roger V. (2003-11-14), "Fetal lung development in the elephant reflects the adaptations required for snorkeling in adult life" (PDF), Respiratory Physiology & Neurobiology, 138 (2–3): 325–333, doi:10.1016/S1569-9048(03)00199-X
  6. ^ Todd, N. E. (2001). African Elephas recki: time, space and taxonomy (pdf). 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.
  7. ^ Todd, N. E. (2005). Reanalysis of African Elephas recki: implications for time, space and taxonomy. Quaternary International 126-128:65-72.
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