For quite some time, there has been debate over the genetic origins of the Borneo's Asian elephants. One theory is that about 250 years ago, the Sultan of Sulu was given Asian elephants as a gift. According to that theory, today's Borneo elephants are descendents of those Asian elephants. But new evidence now suggests that the elephants are instead a distinct population that was isolated 18,000 years ago at the time Borneo was cut off from the mainland.

Find out more: Borneo Elephants: From Pest to Priority (National Geographic)