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This is the VOA SpecialEnglish Science Report.
Scientists say African elephants that live in the forest andthose that live in grasslands are different enough to be consideredseparate kinds, or species. Until now, scientists believed allAfrican elephants were the same genetically. They have longrecognized the clear differences between African and Asianelephants.
One genetic researcher said the difference between the two groupsof African elephants is as large as the difference between a lionand a tiger. Researchers from the United States and Kenya announcedthe discovery in the publication Science.
They examined genetic differences in almost two-hundred Africanelephants in grasslands and forests. They collected tissue from morethan twenty groups of elephants in the wild over a period of eightyears. They did so by firing small sharp objects into the elephants.The darts removed small pieces of skin and then dropped to theground.
The researchers examined the genetic material from the elephants'skin. They found great differences between the African elephantsliving in the forest and those that live on the grasslands.
The grassland elephant has large ears and curving ivory tusks.People can see these elephants in zoos and in visits to Africa. Theforest elephant is smaller and has round ears. Its tusks arestraighter and longer. The ivory is slightly pink in color. Theforest elephant is not often seen in the wild. Only one Africanforest elephant is in a zoo. It is in Paris, France.
The researchers say genetic differences show that the two kindsof African elephants began to develop into separate species morethan two-million years ago. The research also shows that allgrassland elephants are genetically the same. This means they alldeveloped from one recent ancestor. The forest elephants, however,are genetically different from each other. This means that elephantsin forest groups rarely mate and reproduce with members of othergroups.
The researchers say that only about two-hundred-thousand Africanelephants live in the forests. These elephants face a greater threatto their survival than other elephants. The threats are from landdevelopment and other human activity. Scientists say it is importantthat the African forest elephant be recognized as a separate speciesso it can be protected.
This VOA Special English Science Report was written by NancySteinbach.