If you think eating insects is gross, you may be in the cultural minority. Throughout history, people have relished insects as food. Today, many cultures still do.
Ten thousand years ago hunters and gatherers ate bugs to survive. They probably learned what was edible from observing what animals ate, according to Gene DeFoliart, a professor emeritus of entomology at the University of Wisconsin-Madison.
"Eating insects certainly is an old tradition," he said.
The ancient Romans and Greeks dined on insects. Pliny, the first-century Roman scholar and author of Historia Naturalis, wrote that Roman aristocrats loved to eat beetle larvae reared on flour and wine.
Aristotle, the fourth-century Greek philosopher and scientist, described in his writings the ideal time to harvest cicadas: "The larva of the cicada on attaining full size in the ground becomes a nymph; then it tastes best, before the husk is broken. At first the males are better to eat, but after copulation the females, which are then full of white eggs."
The Old Testament encouraged Christians and Jews to consume locusts, beetles, and grasshoppers. St. John the Baptist is said to have survived on locusts and honey when he lived in the desert.
In the mid-19th century Maj. Howard Egan, a superintendent of the Pony Express in Nevada, observed a Paiute Indian hunt where the quarry was neither bison nor rabbit, but rather the wingless Mormon cricket.
Major Egan later described how the Paiute dug a series of large trenches, covered them with straw, then drove hordes of crickets into the excavated trap. The Indians set the straw on fire, burning the crickets alive.
Paiute women then gathered bushels of the charred bugs and brought them back to camp to make flour for bread—an important seasonal source of protein.
Many types of insects appear on menus today. Bugs remain a traditional food in many cultures across Africa, Asia, and Latin America, DeFoliart said.
In Ghana during the spring rains, winged termites are collected and fried, roasted, or made into bread. In South Africa the insects are eaten with cornmeal porridge.
In China beekeepers are considered virile, because they regularly eat larvae from their beehives.
Gourmands in Japan savor aquatic fly larvae sautéed in sugar and soy sauce. De-winged dragonflies boiled in coconut milk with ginger and garlic are a delicacy in Bali.
Grubs are savored in New Guinea and aboriginal Australia. In Latin America cicadas, fire-roasted tarantulas, and ants are prevalent in traditional dishes. One of the most famous culinary insects, the agave worm, is eaten on tortillas and placed in bottles of mezcal liquor in Mexico.
But despite its long tradition—and current favor among at least half of the world's peoples—eating insects is still rare, not to mention taboo, in the United States and Europe.
One reason, DeFoliart said, is that after Europe became agrarian, insects were seen as destroyers of crops rather than a source of food.
"We became invested in livestock, and bugs became the enemy," said David George Gordon, a biologist and the author of The Eat-a-Bug Cookbook.
Manfred Kroger, a professor emeritus of food science at Penn State University in University Park, says what people choose to eat is conditioned by culture.
Many Westerners readily consume shrimp and lobster (which, like insects, are arthropods) along with pork and oysters—foods other cultures reject as dirty.
"We have 200 to 300 staple foods that we pass down from generation to generation—and trying new foods is always a touchy subject," Kroger said.
Kroger is anything but a lone voice in the wilderness when he argues that there are many nutritional benefits to eating insects.
Hamburger, for example, is roughly 18 percent protein and 18 percent fat. Cooked grasshopper, meanwhile, contains up to 60 percent protein with just 6 percent fat. Moreover, like fish, insect fatty acids are unsaturated and thus healthier.
DeFoliart, the Wisconsin entomologist, says that not only are insects nutritious and delicious, they could be an environmentally friendly source of human protein requirements.
"In our preoccupation with cattle, we have denuded the planet of vegetation," DeFoliart said. "Insects are much more efficient in converting biomass to protein."
Insect farming is arguably much more efficient than cattle production. One hundred pounds (45 kilograms) of feed produces 10 pounds (4.5 kilograms) of beef, while the same amount of feed yields 45 pounds (20 kilograms) of cricket.
Noting the widespread use of pesticides in industrial agriculture, DeFoliart said, "People are poisoning the planet by ridding it of insects, rather than eating insects and keeping artificial chemicals off plants that we eat."