AlertNet: Back in 2010, farmers in northern Malawi were advised to stop growing local maize varieties and switch to faster-maturing hybrids, to protect them from a shortening rainy season. Now, less than three years later, the government is urging them to start planting indigenous varieties again, alongside the newer ones, because researchers have found the local maize more resilient to weather extremes. Such stories hint at the difficulty of adapting to changing conditions that can be very hard to predict....