RATS could soon be the next weapon in the fight to detect land mines. A Tanzanian local newspaper reported that a project, a joint enterprise between Sokoine University of Agriculture and a Belgian NGO, is underway to train African giant pouch rats to identify the presence of land mines by smell. The rodents are to be trained to recognise the smell of TNT. According to Belgian researchers, rats are a better choice than dogs in that they have a better sense of smell, are cheaper to keep and maintain and are more resistant to certain tropical diseases. Also as rats are smaller more can be transported and they are suitable for repetitive tasks. Laboratory rats are been trained to mark a mine area and to pinpoint the position of individual landmines. To identify the minefield, laboratory rats are given soil samples to smell, and indicate the presence of dynamite vapour by pressing one of two levers. Once the minefield has been mapped, the rats sniff out a landmine and sit beside it waiting to be rewarded with food, The catch say researchers, is that it may be necessary to have the rats on a leash working an area of maybe 10-15 square metres at a time to prevent them from running off.