Hungry PlanetBy: Peter Menzel, Faith D'Aluisio On the banks of Mali's Niger River, Soumana Natomo and his family gather for a communal dinner of millet porridge with tamarind juice. In the USA, the Ronayne Caven family enjoys corndogs on a stick with a tossed green salad. This age old practice of sitting down to a family meal is undergoing unprecedented change as rising world affluence and trade, along with the spread of global food conglomerates, transform diets