When the civil war in Angola ended 15 tears ago, elephant populations slowly started to return to their pre-conflict grazing grounds. The only problem was millions of landmines remained undetonated across Angola, killing many elephants as they returned to the region. Data collected from collared elephants moving through the affected areas showed the herds had learned to avoid the minefields over the years. Researchers have attributed this to their supreme sense of smell, which is why they are having elephants smell samples collected by unmanned vehicles in areas suspected of having landmines in order to support demining operations.