Are There Dead Wasps In Figs? | Gross Science


Figs are one of my favorite foods. They’re sweet and floral, and there’s something
about the texture that I find so delightful—the outside is soft, but the seeds in the middle
give you this totally satisfying crunch. But it turns out that many species of figs
contain the bodies of dead wasps. I’m Anna and this is Gross Science. Figs aren’t exactly your typical fruit. You can think of them as packages that contain
all of the fig tree’s flowers within them. But if the flowers are trapped inside the
fig how do they get pollinated? Well, that’s where fig wasps come in. In most species, pregnant female fig wasps
carrying pollen are attracted to young figs. They enter through a tiny opening at the fig’s
bottom that’s highly selective—it usually only lets in the exact species of wasps that
pollinate it. But, even the pollinators have a hard time
getting in. Most lose their wings and antennae in the
process. The wasp’s goal is to find a home for her
babies. And the perfect home is inside the fig’s
female flowers—those are the ones that would produce seeds if they were fertilized. So, the mama wasp drops a fertilized egg inside
as many of the female flowers as she can—sometimes, up to a few hundred. But she can’t get to all of them. Along the way, she winds up fertilizing the
rest of the flowers with the fig pollen she’s carrying, and those flowers begin developing
seeds. Once the wasp is finished laying eggs, she
usually dies inside the fig. Each baby wasp begins to grow, encased in
a protective structure that the plant forms called a gall. The male wasps mature first. When they emerge, they find the galls of the
female wasps, many of whom are their sisters, poke inside, and impregnate them before they’ve
even hatched! Then, the males die inside the fig, but not
before boring tiny holes through the fig’s skin. When the females do emerge, the fig has just
started producing pollen. The female wasps pick up some of that pollen
before making their way through the holes their brothers drilled, and go off to find
a new fig to start the cycle again. But the story’s not over. At this point, our fig’s seeds are finally
mature and ready to be planted. And that happens when the ripe fig is eaten
by animals, which poop out the seeds, spreading fig plants far and wide. Of course, humans eat figs, too. So, when you bite into a fig are you actually
eating the bodies of dead wasps? Well, if you’re getting your figs from the
supermarket, then most likely not. See, humans and figs have a really long history—we’ve
probably been domesticating them for over 11,000 years. So, while there are over 750 species in the
world, most of the figs we eat are a species called the “common fig,” which humans
have had a huge hand in creating. In fact, some common figs are seedless and
don’t require pollination at all. Other varieties of common fig do need to be
pollinated, but have separate male and female trees, and we only eat fruits from the female
ones. I’ll put a link in the description to a
great explanation of how common fig pollination happens, but long story short, female wasps
can only manage to lay eggs in the the figs from male trees, not female ones. But they can’t tell the difference between
the two types of trees. So, if a wasp does enter a female fruit, she’ll
pollinate it, and either manage to escape or die inside the fig. And then that fig might make it to your table. Frankly, one wasp here and there isn’t enough
to deter me from eating these things. But if you’re still feeling squeamish, just
think about it this way: by eating that fig, you’re benefitting from a complex and in my
view, beautiful partnership—or, what’s called a “mutualism”— between two very
different species. One that’s been delicately crafted by around
90 million years of evolution. And that certainly whets my appetite—at
least for curiosity, if not for dinner. MMMM! But also ew.

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