SOME VISIONARIES hope that insects will play a big role in future human diets. Insects are nutritious, being packed with protein. Unlike hot-blooded mammals and birds, which use a lot of energy to keep themselves warm, they are efficient converters of food into body mass. And in some parts of the world they are, indeed, eaten already.
Well, maybe. But it will take some serious marketing to persuade consumers, in the West at least, that fricasseed locusts or termiteburgers are the yummy must-haves of 21st-century cuisine. The visionaries might nevertheless prove correct that insects will contribute to human nutrition—just not in the way they imagine.
What is actually happening is that a band of entrepreneurs are breeding insects as animal fodder—particularly fish food. Grown on cheap inputs, then crushed and formed into meal, they will thus provide all of the nutritional advantages the visionaries talk of, but at one remove from people’s dining tables instead of being served up directly for lunch.
The two most promising species are flour beetles and black soldier flies, specifically the larval stages of these animals. Flour-beetle larvae, better known as mealworms (pictured above), have been used as fish food for a long time—they are excellent bait for anglers and are bred commercially on a small scale for this...