Proboscidea
| Proboscidea | |
|---|---|
| Scientific classification | |
| Kingdom Information | |
| Domain | Eukaryota |
| Kingdom | Animalia |
| Subkingdom | Bilateria |
| Phylum Information | |
| Phylum | Chordata |
| Sub-phylum | Vertebrata |
| Infraphylum | Gnathostomata |
| Class Information | |
| Superclass | Tetrapoda |
| Class | Mammalia |
| Sub-class | Theria |
| Infra-class | Eutheria |
| Order Information | |
| Order | Proboscidea |
| Population statistics | |
Proboscidea is an order of mammals distinguished by an elongated facial trunk, of which the the three species of elephant are the only living examples. The order was proposed in 1811 by German entomologist and zoologist Johann Karl Wilhelm Illiger (1775 – 1813).
Description
Proboscidea include the largest land animals alive today, as well as possibly the largest land mammals of all time. Of living species the largest African elephant (Loxodonta aficana) ever recorded (the Fenykovi elephant, now in the Smithsonian Institution) was shot in Angola in 1955; it weighed about 10.7 tonnes (12 U.S. tons) and stood 13 feet, 2 inches at the shoulder.[1][2] The slightly-smaller Asian elephant (Elephas maximus) had a maximum recorded height of 11 feet 9 inches and eight tons in one individual recorded in 1985. Extinct species were even larger; at least two species - Mammut borsoni and Palaeoloxodon namadicus - had a body mass exceeding in size the largest known land mammal (Indricotherium) as well as some sauropod dinosaurs.[3][4]
Apart from their massive size their most striking features are a long trunk, or proboscis, a flexible nose strong enough to lift heavy objects, and at least as is known in living elephants these trunks contain 150,000 individual muscles. Their skin is up to 1.5 inches thick and gray in color, with the skin of African bush elephants more heavily wrinkled than their Asian counterparts; many extinct species, particularly the woolly mammoth (Mammuthus primigenius) had extensive body hair. All species possess ivory tusks, with several species bearing tusks in both the upper and lower laws. To support the weight of the tusks - which can be 11 feet or more in length - probscideans have a very large head bearing a number of air-filled cavities which not only reduce the weight of the entire skull, but also allow for an enormous increase in the volume of the skull surface, allowing the attachment of large neck muscles and enabling these animals to bear the weight of, and effectively use, the ever-growing tusks.