Landmines have a very long history. The first mines were apparently designed and built by the Chinese in the 13th century. Deadly during the wars in which they were buried, they remain deadly for decades afterwards, maiming and killing civilians by the hundreds. For that reason, the Ottawa Treaty, which only covers anti-personnel mines, was drawn up in 1997 and as of 2010, it has been ratified by 156 countries. The most powerful countries in the world, including the United States, Russia, and China, have not signed.

The problem of active minefields remains long after wars are concluded. Locating and then removing them involves the use of metal detectors but metal detectors are useless against almost all anti-personnel mines, because they are constructed of plastic, specifically to prevent detection. Dogs are used to find mines because they can smell the chemicals used in the devices, but dogs are expensive to train. Enter rats. Watch this very interesting video.

Bart Weetjens came up with the idea and established a non governmental organization (NGO) called APOPO to advance his mission. There is also an associated website called HeroRats that explains in more detail in the FAQ section how the rats are trained and used. Fascinating.