The rats involved in finding land mines in Mozambique have been bred to be the size of raccoons, The Boston Globe reports. While the squads of mine-sniffing rats were mocked at first, officials are considering using them in the Democratic Republic of Congo, Zambia and other countries where unexploded mines remain common.
In Tanzania, trained rats sniff sputum samples at four medical clinics. The rats have found more than 300 cases of TB that hadn't been diagnosed by medical staff.
Bart Weetjens of Belgium got the idea for the trained rats while he was in Africa working on land mines. The rats are trained to scratch when they smell the vapor from land mines or the smell of disease. When they scratch, their handlers signal them with a clicker and then reward the animals with a piece of fruit or a nut.
Weetjens was asked why the rats don't simply scratch to get food.
"That would be human behavior," he told the Globe. "The rats are more honest."