for National Geographic News
Genetic fingerprinting shows that Africa's forest and savanna elephants are as different from one another as lions and tigers and should be considered as two genetically distinct species, an international group of researchers reports.
Up until now, elephants have been divided into two speciesAsian and African. However, there has been considerable debate among experts as to whether the differences between Africa's forest and savanna elephants were significant enough to identify them as separate species. The DNA evidence, reported in the August 24 issue of the journal Science, provides a definitive answer to the long-debated controversy.
The finding has implications for both international law and conservation strategies.
If there are two species, there are both fewer elephants in each population and they're more endangered than previously assumed, according to Nicholas Georgiadis, a biologist at the Mpala Research Center in Kenya and co-author of the study.
Seventy years ago there were between three million to five million elephants in Africa. Today there are around 500,000 elephants in Africa. Forest elephants comprise around one-third of that number, living in the equatorial forests of central and western Africa. The savanna or bush elephant is found throughout the grassy plains and bushland of the continent.
Forest elephants are smaller and have straighter and thinner tusks, rounded ears, and a distinct skull shape.
The social structure of the two species also differs. The family units of savanna elephants typically contain about ten individuals. Sometimes several families join to form a clan with up to 70 members, led by a large female. Forest elephants live in much smaller groups.
The differences between the two have long been noted, says F.V. "Loki" Osborn, an elephant researcher based in Zimbabwe.
Raphael Ben-Shahar, an elephant expert at Oxford University, says, "Up until DNA fingerprinting tests, species were defined on the basis of morphological and anatomical differences." Using the old classification yardsticks, the forest elephant was merely a subspecies of the savanna elephant. However, there was widespread disagreement among taxonomists as to whether the differences between the two elephant types were significant enough to denote separate species, he says.
The DNA evidence should put the controversy to rest.
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