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Detector elephants: gentle giants sniff out explosives

- Wits University

An African elephant detects dangerous TNT using its extraordinary sense of smell.

Shot in November 2015, this incredible footage shows Chishuru, a 17-year-old male bull, carefully checking a row of white plastic buckets – one of which contains the explosive material.

The huge animal raises its right leg to signal that he has found the tiny amount of TNT which is placed on a cotton swab.

In 2007, researchers discovered that an elephant herd in Angola, who were being tracked using GPS technology, purposely avoided landmine fields left over from the civil war – which had claimed the lives of many elephants.

When Chishuru was tasked with finding the TNT for the first time in over a year, he did so quickly without any refresher training.

“Elephants have a much better sense of smell than dogs do,” says Miller.

“We can say this primarily because they have more than double the amount of olfactory receptor genes in their DNA. Not only do elephants have a better sense of smell, but there is a lot less effort required in maintaining them as a biosensor.”

Michael Hensman, manager of Adventures with Elephants, said they initially set out to try and figure out how elephants were able to avoid those areas and it seems to be related to olfaction.

“We are never going to put elephants in to a dangerous situation like minefields where they could get hurt,” he says.

“The idea is to remotely collect samples and bring those samples out to the elephants for landmine area reduction.”

This research has been largely funded by the US Army Research Office. Researchers are also looking at other applications for the elephants, including cancer and diabetes screenings.