Do we know enough about all crops of the world before we step into teasing evolution within the pool of a tiny number of species? Not well discussed and not well understood, an important tropical crop in Africa and other parts of the world reports: "Yam not a grain, yet I feed 60 million people every day. Yam a productive and valuable crop for farmers, getting as large as 2.5 meters long and weigh up to 70 kilograms. However, you know so little about how much I can give". Read the full story about the efforts of the Global Crop Diversity Trust (GCDT) for saving endangered yams in this month's Scientific American.