Although Borneo is home to many animals found nowhere else in the world, the largest creature roaming its jungles, the Asian elephant, had always been dismissed as a descendant from domesticated animals brought in during colonial times. A new genetic study proves otherwise. They are home-grown, ancient pachyderms, deserving of a subspecies name of their own.
Elephants in Borneo are limited to the northern tip of the island. The story goes that the population stems from a few animals presented to the Sultan of Sulu, who ruled that part of Borneo, by the East India Trading Company around 1750, says geneticist Prithiviraj Fernando of Columbia University in New York City. But in the 1950s, zoologists noted that the Borneo population looked different from other Asian elephants: They have smaller skulls and some differences in the tusks, which did not jibe with their supposed feral background.
To solve this conundrum, Fernando and colleagues from the United States, India, and Malaysia delved into the DNA of the animals. They collected dung and blood samples from 20 elephants on the Malaysian part of its range to isolate one mitochondrial and five chromosomal genes. They then compared these with the same genes in hundreds of elephants from elsewhere in southern Asia. The results do away with the myth of recent introduction, says Fernando. Genetically, the Borneo elephants are very different and cannot be matched with any known populations, domestic or wild. Based on the mutation rate in the mitochondrial gene, the researchers estimate that the animals became isolated on Borneo some 300,000 years ago, when the island was still part of the Asian mainland. Indeed, after additional anatomical studies, they will probably deserve to be raised to subspecies level, they predict. The findings are published this week by the Public Library of Science, Biology.
Conservationists believe that the new data warrant more stringent protection for the dwindling population of 1500 or so elephants, which are short of natural habitat and are often shot by disgruntled plantation owners. Michael Bruford, a conservation geneticist at Cardiff University in Wales who runs a research project on large mammals in Borneo, says the findings mean Borneo's elephants are more than just a curiosity--they're a unique population worthy of greater appreciation.
Related sites
A story on Prithiviraj Fernando's work
World Wide
Fund for Nature Malaysia's site on Asian Rhino and Elephant
Conservation Strategy
)
)
)
)
)
)
)
)
)
)
)
