THE SOLUTION
Tom Gilbert, a geneticist at the University of Copenhagen, has found that leeches are a great way to track down rare creatures. He was inspired after a colleague monitoring rare tapirs in Malaysia was bitten by a terrestrial leech (a common annoyance in tropical rainforests) and wondered whether the blood inside it could be used for DNA analysis. Gilbert tested the idea by feeding 40 leeches goat blood. After he ground them into a paste, he found that every one contained goat DNA, even four months after its last meal. In 2010, Gilbert tried the method on 25 leeches that had been collected in Vietnam. “We kind of hit the jackpot,” he says. Twenty-one leeches contained DNA from mammals, two of which were extremely rare. Although there was no evidence of the saola, Gilbert did find DNA from the Annamite striped rabbit. (Scientists first discovered the animal in a Laotian food market in 1995 but have hardly seen it since.) Gilbert is now analyzing the recent meals of leeches collected in countries including Indonesia, Malaysia, and Madagascar.
AND: Here’s a look at some of zoology’s most wanted rare species.
1) THYLACINE
The striped meat-eating Tasmanian tiger was a marsupial the size of a large dog. Though experts largely agree the last one died in a zoo in 1936, some people hold out hope.
2) JAVAN RHINO
This heavily hunted ungulate may be extinct, but up to 50 might survive on the western tip of Java.
3) SAOLA
Scientists estimate that between a few dozen and a few hundred of this deerlike animal live in the remote Annamite mountains of Vietnam and Laos.
4) GREATER BAMBOO LEMUR
Despite its name, this primate weighs only five pounds. Researchers suspect that some 100 to 160 live in disappearing bamboo forests in Madagascar.
5) ANNAMITE STRIPED RABBIT
Scientists believe that this rabbit (and its reddish rump) might be hiding in the same areas as the saola.
