Evolution and taxonomy of African elephants

African elephants

Genetic research has raised the possibility that the two classic forms of elephant in Africa are separate species rather than subspecies of Loxodonta africana. Museum research has uncovered populations with a mosaic of features. 

There are two forms of African elephant, with different distributions and very marked physical differences:

• The bush or savanna elephant is distributed in eastern and southern Africa. It has a large and rangy body, very large and triangular ears, massive tusks which curve outwards and forwards and a distinctly saddle-shaped back.
• The forest elephant occupies much of central and western Africa. It has a distinctly smaller, more compact body, smaller, rounded ears, narrow, long and downward-pointing tusks and a straighter back.

Subspecies or species?

In the past, the two forms have been treated as subspecies of Loxodonta africana:

• L. a. africana (African bush elephant)
• L. a. cyclotis (African forest elephant)

Recent genetic research has raised the possibility that they are separate species:

• L. africana
• L. cyclotis

This question is important because it helps shape the conservation policies of international organisations like:

• The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)
• International Union for Conservation of Nature (IUCN), which publishes the IUCN Red List of Threatened Species

Our research

• Transition zone elephants
  A 2004 expedition to Ghana studied a population of elephants in the transition zone between the classic savannah and forest forms. We found a mosaic of features, including body size as large as savannah elephants, tusk and head shape like forest elephants and intermediate ear shape.
• Ear shape
  A further study investigated ear shape by comparing a series of populations across Africa. Although the difference between some classic forest and savannah populations is clear, others show a range of forms, making them difficult to classify as one or the other.

These studies indicate that both genetic and anatomical data are needed to correctly classify all populations of elephants. We hypothesise that ‘intermediate’-looking animals are a result of hybridisation, or the adaptation of some populations of forest origin to a more open environment in West Africa.