Elephants have become the latest creatures to join humans in the battle to detect explosives and potentially save lives.
Researchers in South Africa have proven that the enormous creatures can sniff out explosives using their keen sense of smell.
It was first noticed that elephants can detect explosives in Angola, when the creatures returned following a war in 2002, which left the ground littered with mines.
Researchers wanted to uncover whether elephants could smell the explosives, or whether they avoided certain areas because elephants had died there in the past.
To make their findings, experts gave elephants in Bela-Bela, a town north of the South African capital of Pretoria, smelling tests.
The remarkable animals were able pick up TNT samples 73 out of the 74 times in a line of buckets, according to Ashadee Kay Miller, a zoology student at the University of the Witwatersrand in They only failed 3.6 per cent of the time over 502 buckets that contained the explosive, which was dissolved in acetone on filter paper. All other buckets were filled with acetone and filter paper only.
And in a second set of tests, the animals detected TNT in 23 out of 23 buckets when “distractor odours” such as tea, bleach, soap and gasoline were placed in the other buckets, she said.
The study received major funding from the US military. But Stephen Lee, head scientist at the US Army Research Office, said that despite their skills, the animals won’t be put to work at war.
“There's never an intention that we're going to use elephants on the battlefield,” Lee said.
Instead, researchers aim to learn how an elephant smells, and apply this to electronic sensors.
Other creatures which help to sniff out explosives include dogs, who can also be made sensitive to contraband and other illegal items; while a group called APOPO has deployed rats to detect mines in Angola and Mozambique. The rodents are also tasked with screening people for Tanzania for tuberculosis, which they do by evaluating sputum samples.
In Croatia, where mines were left from the 1990s Balkan wars, researchers noted that bees gathered at pots containing a sugar solution mixed with TNT, though the insects have not been used for de-mining.