Extant Elephants
Living elephants belong to two genera: Loxodonta and Elephas. They are thought to have shared a common ancestor with the extinct mammoths and all members of the Elephantidae. In 2006 Shoshani incorporated all extant and extinct Elephantidae, including stegodontidae and Primelephas, into the superfamily he called Elephantiformes.
Top: A female African Bush Elephant with her calf Middle: Range of the living African Elephant Above: Map showing the global distribution of Loxodonta remains.
The family Gomphotheriidae, which includes the Cuvieronius and Gomphotherium, is closely related to the Elephantidae along with the family Mammutidae which includes the mastodons (not to be confused with Mammuthus).

Both species of Loxodonta were previously combined under the same title ‘African Elephant’ as there was little evidence to separate them. However, in 2010 DNA sequence analysis was carried out resulting in the separation of the two subspecies because they are genetically diverse regardless of morphological similarity.

Loxodonta, greek for ‘oblique sided tooth’, live in Africa. They are larger in stature than the Elephas of Asia and fossils of this genus have only ever been found in Africa. It is therefore presumed that this genus is more primitive than the other extant genus residing in Asia. The two species of Loxodonta are:

African Bush Elephant (Loxodonta Africana)

The larger of the two African elephants, this species lives in sub-Saharan Africa however, its fossils have been found as far north as Libya. African Elephants have two ‘fingers’ on the end of their trunks and both males and females have tusks. The Bush Elephant only has four toenails on its front feet and three on its back feet; this is different to both the Forest Elephant and Asian Elephant who both have five toenails on their front feet and four on the back feet.

African Forest Elephant (Loxodonta cyclotis)

The Forest Elephant is found, unsurprisingly, in central Africa mainly in the Congo Basin. They are smaller than the Bush Elephant and it was originally thought there was a third species; the Pigmy Elephant living in the Congo basin. Genetic analysis has shown that these are just smaller versions of Forest Elephants, probably due to lower cover and different environmental conditions. These should not be confused with ancient ‘dwarf elephants’. The Forest Elephant has subtle differences in morphology to the Bush and Asian Elephants, for example they have a smoother forehead which is less convex and rounder ears. The Forest Elephant is not classified by the IUCN however its vulnerability status varies throughout its habitat due to habitat fragmentation.

The Asian Elephant (Elephas maximus)

Elephas maximus is the extant species of Asian Elephant. There are three subspecies denoting habitat area: Sri-Lanka Elephas maximus maximus, Sumatra Elephas maximus sumatranus and mainland Asia Elephas maximus indicus. The Asian Elephant is the largest land animal in Asia however, it is still smaller than the African Elephant. Their ears are smaller and flatten against the body; this could be due to differences in heat loss strategy and a decreased need to hear over long distances. The subtle differences continue with a different number of toenails and only one ‘finger’ on the trunk. Also, female Asian Elephants do not have tusks.

The Asian Elephant is listed as endangered by the ICUN however, poaching still occurs and numbers are declining rapidly. Despite this downward trend, humans and elephants have a good working relationship with elephants being domesticated and trained to carry heavy items during construction; they are also large tourist attractions. It is quite ironic how elephants are being used by humans to pull down trees and transport their own natural habitat for human use. Perhaps this issue should be addressed by conservationists.

Top: Elephas maximus Above: Map showing the global distribution of Elephas remains.
Above: an Asian elephant hauling munitions in Sheffield in 1917
Relationship with humans

Poaching is still one of the many problems conservationists face when protecting elephants; elephants are classed as a ‘near threatened species’ on the IUCN Red List and a ban on the ivory trade in 1989 has greatly reduced the number of elephants being needlessly killed however, illegal trade is still rife. One documented incident recorded the killing of more than 100 elephants in the Zakouma National Park, Chad in 2006.

Another major issue with elephant conservation is the fact that the human population is expanding and settlements are moving into natural elephant habitat. The species seen to be most affected by this is the African Forest Elephant (Loxodonta cyclotis). Its habitat has been severely fragmented over the past few years and population numbers are declining rapidly. Human safety has to be taken into consideration and many elephants are shot because they enter the settlement and raid houses for food. Elephant intelligence studies suggest that they do not forget favourite areas and if humans have settled in the elephant habitat then confrontation is likely to occur.

Elephants have a large part in human history; they were traditionally tamed in Asia and used in large numbers to scare off the enemy during wars. War elephants are thought to have been influential in Hannibal’s victory over the Roman Empire in 218 BC. Elephants are able to move over difficult terrain and are still used today to enter the most inaccessible parts of the jungle. Most recently, elephants were used by the BBC to carry cameras filming tigers in their natural habitat.

Reference

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