Elephants can 'sniff out' explosives

Researcher Ashadee Kay Miller at the University of the Witwatersrand in Johannesburg said that the giant animals were able pick up TNT samples 73 out of the 74 times in a line of buckets.

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.

Stephen Lee, head scientist at the US Army Research Office, said that there's never an intention that they're going to use elephants on the battlefield, 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, which 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.