Africa's Forest Elephants Called Separate Species

The following story was written by Will Dunham and ran in the August 23, 2001, issue of Reuters.

Elephants dwelling in Africa's lush tropical rain forests are genetically distinct from the better-known elephants that roam the continent's grasslands and merit being classified as a separate species, scientists said on Thursday.

All of Africa's approximately half a million elephants until now have been considered a single species that officially is listed as "threatened." But a team of elephant experts and geneticists, in a study appearing in the journal Science, found that the two types of African elephants are no more related at the genetic level than lions and tigers and should be regarded as distinct species. The researchers said the genetic evidence indicates the two African species diverged about 2.6 million years ago. This means the world has three species of elephants -- the world's largest land animal -- including the Asian elephant.

The designation of Africa's forest elephants and those living on the vast savannas as separate species has important conservation implications, particularly because many forest elephants live in forests in politically unstable Central African nations, conservationists said. Scientists long have noted how different the forest elephants look from their savanna cousins. Nick Georgiadis, a biologist at the Mpala Research Center in Kenya, said he recalls his reaction when he first saw forest elephants.

"I was certainly accustomed to seeing savanna elephants and was amazed. The forest elephants are totally different. It's a completely different animal," he said in a telephone interview from South Africa.

Forest elephants are smaller than the savanna elephants -- which grow up to 11 feet (3.3 metres) at the shoulder, 25 feet (7.5 metres) long and weigh six tonnes -- and have more rounded ears and straighter, thinner tusks. The skull shape also differs between the two.

GENETIC DIFFERENCES SOUGHT

Georgiadis joined with geneticists from the U.S. National Cancer Institute (NCI) in Frederick, Maryland, to test whether genetic differences accompanied the morphological differences. He spent eight years collecting tissue samples from 195 elephants from 21 separate populations in 11 of the 37 nations where the behemoths live. To collect the samples, Georgiadis shot darts into elephants in the wild. The darts retrieved a plug of skin then popped out and fell to the ground, leaving the animal unhurt.

"They're really quite distinct," O'Brien said. "It seems that there is no question that reclassifying the African elephant as two separate species is warranted," added University of Washington conservation biologist Samuel Wasser.

The differences between the forest and savanna elephants is more than half as big as the differences between the African elephants and the Asian elephant, the researchers said. The data also indicated there was scant inter-breeding between the African forest and savanna elephants.

Most people have never seen a forest elephant. Only one lives in captivity, housed in the Paris Zoo. Of the roughly 500,000 elephants in Africa, about 150,000 are forest elephants and 350,000 are savanna elephants, experts said. Most of the forest elephants can be found in the dense forests of the Democratic Republic of Congo, the Central African Republic and Cameroon, according to Peter Stephenson, coordinator of the World Wildlife Fund's African elephant program. The largest concentrations of savanna elephants are in Botswana, Zimbabwe, Zambia, South Africa, Tanzania and Kenya, he added.

"The forest elephant is actually found in much more dangerous territory," in terms of human threats from wars, logging, mining, development and poaching, Stephenson said.

The scientists proposed the scientific name Loxodonta cyclotis for the Forest elephants and retaining the existing species name Loxodonta africana for The savanna elephants.

NCI scientists Stephen O'Brien, Alfred Roca and Jill Pecon-Slattery sequenced portions of four genes from each of the samples to measure the genetic differences. The DNA differences between the two types of African elephants were not quite as broad as the genetic divergence between human beings and chimpanzees, for example, but was as great as the differences between tigers and lions, they found.