I recently dropped a small fortune on a haul of purpleish figs at the farmers market. What was I going to make? What wasn't I going to make? Figs in a stunning caprese salad. Figs on yogurt with honey and pine nuts. Figs covered in bacon bits and maple syrup. Then, while doomscrolling, my fig dreams were crushed by one 56-word viral tweet. I learned that many figs are pollinated by fig wasps, and that those tiny bugs die inside each fleshy pod. The bounty in my fridge suddenly took on a sinister quality. I needed to know: Were all of my figs filled with dead wasps? The answer, I learned, is both yes and no.
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Figs have many secrets. They are actually inverted flowers. Each hollow ball of vegetal tissue is lined with hundreds of tiny buds that bloom inside the pod, says ecologist Mike Shanahan, author of Gods, Wasps and Stranglers: The Secret History of Fig Trees. The flowerettes in certain edible varieties produce a fruit-covered seed, which is what gives some figs their iconic crunch. Technically, they're known as aggregate fruits, says Louise Ferguson, an extension specialist at the UC Davis Department of Plant Sciences. In other words, the interior of each fig develops from hundreds of individual fruiting flowers.
These days, many of the fig varieties that we buy in grocery stores and at farmers markets in the US don't require pollination. Mission, those purplish-black ones I bought, Sierra, Celeste, Adriatic, Kadota, and the Brown Turkey fig can all self-pollinate, says Ferguson. But the Calimyrna, which has a yellow-green skin and is typically sold dried, requires fig wasps for pollination. "There's no real way to tell from the outside, but if the fig contains seeds it will have been pollinated [by a fig wasp]," says Shanahan.
Because sweet, shy figs bloom internally, many of the 800-plus varieties across the world require an intimate type of pollination to ripen into an edible fruit. All figs are made up of both male and female flowers. But the ones we eat are generally harvested from dioecious species, says Shanahan. In these (about 400) varieties, all the figs on each tree behave as either male or female.
To pollinate these species, a female fig wasp, just a couple of millimeters long, forces her way into a non-edible, unripe male-behaving fig where she lays her eggs in the flowers. Along the way, her antennae snap and her wings are yanked from her body-"it's a tight squeeze," says Shanahan-leaving her no way out. Her wingless male offspring mate with the winged female offspring (yes, their sisters) before using their huge jaws to chomp tunnels through the fig that will allow the ladies to leave.
But before she bids adieu, that fertilized female wasp collects pollen from the male flowers. Then she squeezes out the engineered escape routes, leaving her brothers and mother for dead inside the fig. It's her duty. Out in the world, she takes flight in search of specific figs, guided by smell, in which to lay her eggs. If the female wasp enters a male-behvaing fig, the process repeats identically; she sacrifices her life to further the cause. But if she mistakenly burrows into a female-behaving fig, there's no room for her to lay eggs. "She will only pollinate these flowers, and will die without producing offspring," says Shanahan. These pollinated flowers inside the fig pod then produce individual fruits and seeds, which ripen to attract seed-dispersing animals (to poop into more fig trees) and humans like me (to turn into baked custard).
Either way, the life of a female fig wasp is rarely greater than 48 hours-not even long enough for her to eat a meal-and all roads lead to certain death.
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"There's no fig wasp in there by the time people are eating the fruit," says Ferguson. The female fig produces an enzyme that completely digests the exoskeleton before hungry humans can take a bite. To be clear: "The crunchy bits are seeds, not wasp parts," she adds.
Humans started cultivating figs about 10,000 years ago, says Shanahan. But the relationship between fig trees and their pollinator wasps is one of the tightest and longest running codependencies (in a good way) that you'll find in nature. Each species of wasp can only pollinate its corresponding species of fig. And both fig and fig wasp are utterly reliant on one another to survive-a phenomenon called mutualism. It's a coevolution that's been happening for around 80 million years, says Shanahan. "The relationship was going on long before the last of the giant dinosaurs were extinct."
Though you mightn't be able to sense the fig's vitality from a store-bought cookie, they're one of the most essential plants on earth. Their pods feed more animals than any other fruit, says Shanahan. This is because figs are grown year-round, and are available to birds and mammals when many other foods aren't. It's a silver lining born of the relationship between fig and fig wasp. Because of their short lifespans, "there must always be some unripe figs for them to find and lay eggs in," says Shanahan. "Otherwise, they would go extinct."
I'm not going to let the well-digested remains of a bug keep me from eating this ancient treat. As Daniel Janzen wrote in the 1979 paper, How to Be a Fig, "Who eats figs? Everybody." Long live the fig-and long live its precious little fig wasps.