Some figs need fig wasps to pollinate their fruit. But are we eating dead wasps every time we bite into a fig?
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Imagine for a minute that you’re a pregnant woman. Still with me, guys? Now, the only way you can give birth is if you crawl into a small, cramped cave made out of chocolate. And the tunnel to this cave is so cramped that the only way you can get through is by cutting your own arms off “127 Hours” style. Once you’re in this cave you give birth! Then you eventually die from either exhaustion or starvation.
Sounds pretty grim, right? As if giving birth wasn’t difficult enough, what I just described to you is the life cycle of the fig wasp. Their role in the pollination of figs is crucial, both to the propagation of their species and the survival of fig trees.
This arrangement between wasp and plant is called “mutualism,” and it’s evolved over millions of years. Without the wasps you wouldn’t have figs. And vice versa. And yes, most of the figs we eat contain at least one dead wasp.
But more on that later. First, let’s talk pollination.
A fig is technically just a flower with its petals folded inside. There are male figs – which are inedible, and called caprifigs – and female figs, which we eat. But in order to create seeds (and tasty fruit), the female figs need to receive some pollen from the male figs. Since the figs’ reproductive bits are tucked away, wind and bees can’t help as they do with lots of plants. Enter the fig wasp.
So okay… let’s get away from the whole pregnant lady/chocolate metaphor thing and break down how this wasp/fig mutualism process works. For a dude fig plant to share its pollen with a lady fig plant, a female fig wasp needs to enter a male fig. She crawls through a narrow passage in the fig called an ostiole. It’s so cramped that her wings and antenna break off along the way.
But the messed up thing is that these lady fig wasps don’t know is whether they’re entering a male caprifig or a female fig. If it’s a caprifig, she’ll find its male flower parts perfectly shaped for her to lay eggs into. The eggs hatch into larvae and grow within the fig’s petals.
The male wasps hatch first and are born blind and flightless. They mate with their female counterparts (yes… I guess they’re technically brothers and sisters) and start eating an exit tunnel through the fig. The wasp dudes can’t escape, though, so they die inside.
But the females collect the fig’s pollen, crawl out of the tunnel and fly away in search of a new fig plant to lay their eggs in. These wasps are only a few millimeters long, but they can fly up to 20 kilometers (12.4 miles) to find the right species of fig plant. When they arrive, they deposit their natal fig’s pollen, lay their eggs, and the whole process starts over again.
But if a female wasp enters a female fig, she won’t be able to lay her eggs because of a long part of the flower called a stylus. She’ll probably die, but at least she’s delivered the pollen. An enzyme inside the fig called ficin breaks down her corpse into protein, ingesting the dead wasp and making it part of the ripened fruit.*
Just so we’re clear, those crunchy bits you’re chewing in figs aren’t bits of dead wasp or larvae; they’re the fig’s seeds. And anyway, you should get used to the idea of occasionally eating an insect by accident. The FDA considers certain amounts of insect content in various foods “natural” and “unavoidable” – and it’s really not hazardous, just gross.
Nature’s Little Magician The Fig Wasp. By: Andersen, Christie B., Cricket, 00906034, Sep2005, Vol. 33, Issue 1
Fig-Wasp Upset. By: Milius, Susan, Science News, 00368423, 4/26/2003, Vol. 163, Issue 17
Nature’s recourse. By: Milius, Susan, Science News, 00368423, 7/31/2010, Vol. 178, Issue 3
Big on figs. By: Kinnaird, Margaret, International Wildlife, 00209112, Jan/Feb2000, Vol. 30, Issue 1