Sri Lanka, March 25 -- This piece is written in the context of the searing heat experienced in the country. It is a warning to study and respond.

Food systems have been changing since the beginning of human history, during which humans hunted and gathered for food nomadically. By contrast, today's food systems are complex and globally interconnected, as food products may be grown in the United States, processed in China, and then distributed in South America. Throughout history, parts of the world have experienced continuous periods of hunger, often because of war, plague, or hostile weather. The past 70 years' technological advancements counteract this, and increasing global cooperation has begun to suggest the possibility for nations t...