WEBVTT - Do Figs Really Have Dead Wasps In Them? 0:00:02.040 --> 0:00:09.879 Welcome to brain stuff from how stuff Works. Hey, I'm 0:00:09.960 --> 0:00:12.880 Christian Seger, and this is brain stuff. Imagine for a 0:00:12.920 --> 0:00:16.279 minute that you're a pregnant woman. Still with me, Guys, now, 0:00:16.320 --> 0:00:18.280 the only way you can give birth is if you 0:00:18.400 --> 0:00:22.040 crawl into a small, cramped cave made out of chocolate, 0:00:22.360 --> 0:00:24.560 and the tunnel to this cave is so cramped that 0:00:24.600 --> 0:00:26.759 the only way you can get through is by cutting 0:00:26.760 --> 0:00:30.520 your own arms off a seven hours style. Once you're 0:00:30.520 --> 0:00:34.040 in this cave, you give birth, then you eventually die 0:00:34.159 --> 0:00:38.000 from either exhaustion or starvation. But guess what, you gave 0:00:38.040 --> 0:00:41.880 birth to fraternal twins. Unfortunately, your son was born blind 0:00:41.960 --> 0:00:44.120 and all he can do is dig more tunnels by 0:00:44.200 --> 0:00:47.479 chewing through the chocolate. Your daughter needs these tunnels to 0:00:47.479 --> 0:00:50.760 get out so she can begin this horrible reproductive cycle 0:00:50.960 --> 0:00:55.000 all over again. Sounds pretty grim, right, as if giving 0:00:55.000 --> 0:00:57.600 birth work difficult enough. What I just described to you 0:00:57.720 --> 0:01:00.440 is the life cycle of the fig wasp. Their role 0:01:00.480 --> 0:01:03.240 in the pollination of figs is crucial both to the 0:01:03.240 --> 0:01:07.280 propagation of their species and the survival of fig plants. 0:01:07.319 --> 0:01:11.160 This arrangement between wasp and plant is called mutualism, and 0:01:11.200 --> 0:01:14.240 it's evolved over millions of years. Without the wasp, you 0:01:14.240 --> 0:01:17.520 wouldn't have figs and vice versa. And if you're following 0:01:17.520 --> 0:01:20.520 my logic here, yes, that means that most of the 0:01:20.520 --> 0:01:23.320 figs we eat have at least one dead female wasp 0:01:23.480 --> 0:01:27.679 inside of them. Because we're usually eating processed figs, we 0:01:27.800 --> 0:01:30.640 often don't realize that a fig is technically just a 0:01:30.680 --> 0:01:34.840 flower with its petals folded inside. In the late nineteenth century, 0:01:34.959 --> 0:01:38.880 American farmers started importing fig trees to California, but they 0:01:38.920 --> 0:01:42.600 couldn't figure out why their trees were fruitless. Finally, after 0:01:42.640 --> 0:01:45.679 traveling to Turkey, they observed how fig wasps emerged from 0:01:45.720 --> 0:01:48.960 the edible figs and flew to the inedible ones. One 0:01:48.960 --> 0:01:52.120 grower went back to California with this knowledge and performed 0:01:52.160 --> 0:01:56.560 the first artificial pollination on his trees by manually transferring 0:01:56.600 --> 0:01:59.960 pollen with a toothpick. When he cut open the fruit, 0:02:00.040 --> 0:02:02.440 tea thought he saw seeds in the figs, but what 0:02:02.480 --> 0:02:05.720 he was looking at was actually wasp larvae. It wasn't 0:02:05.800 --> 0:02:09.919 until eight that the U. S Department of Agriculture experimented 0:02:09.919 --> 0:02:14.080 with live fig wasps. After several seasons, the wasps and 0:02:14.240 --> 0:02:18.800 the fig trees finally produced a successful crop. Today, farmers 0:02:18.800 --> 0:02:22.320 separate their male and female trees over a distance and 0:02:22.400 --> 0:02:26.680 use controlled wasps delivered in paper sacks to guarantee that 0:02:26.720 --> 0:02:30.520 their figs will ripen. Turkeys still the largest producer of 0:02:30.560 --> 0:02:33.480 figs in the world, but in just a century, California 0:02:33.520 --> 0:02:38.360 became the second largest, registering fifteen thousand metric tons of 0:02:38.400 --> 0:02:42.120 the fruit per year. So, okay, let's get away from 0:02:42.120 --> 0:02:45.320 the whole pregnant lady chocolate metaphor thing and break down 0:02:45.400 --> 0:02:50.000 how this fig wasp mutualism process works. For a fig 0:02:50.000 --> 0:02:53.080 plant to share its pollen with another, a female fig 0:02:53.120 --> 0:02:56.840 wasp needs to enter an unripe fig. She crawls through 0:02:56.919 --> 0:03:00.560 a narrow passage in the fig called an osteo. It's 0:03:00.600 --> 0:03:03.520 so cramped that her wings and antenna break off along 0:03:03.600 --> 0:03:06.400 the way, But it doesn't matter, because, as Juicy j 0:03:06.600 --> 0:03:09.960 once said to Katy Perry, there's no going back. But 0:03:10.080 --> 0:03:13.320 what these lady fig wasps don't know is whether they're 0:03:13.440 --> 0:03:17.840 entering a male capra fig or an already edible female fig. 0:03:18.200 --> 0:03:21.120 If it's a capra fig, she'll find its male flower 0:03:21.200 --> 0:03:24.120 parts are perfectly shaped for her to lay eggs into 0:03:24.639 --> 0:03:28.200 the eggs hatch into larvae and grow within the figs petals. 0:03:28.840 --> 0:03:32.600 The male wasps hatch first and are born blind and flightless. 0:03:32.960 --> 0:03:35.960 They mate with their female counterparts yes, I guess that 0:03:36.040 --> 0:03:39.320 technically means their brothers and sisters, and then they start 0:03:39.400 --> 0:03:43.000 eating an exit tunnel through the fig. The wasp dudes 0:03:43.120 --> 0:03:46.400 can't escape, though, so they die inside, but the females 0:03:46.440 --> 0:03:48.920 collect the figs pollen, crawl out of the tunnel, and 0:03:49.000 --> 0:03:51.440 fly away in search of a new fig plant to 0:03:51.560 --> 0:03:54.720 lay their eggs in. These wasps are only a few 0:03:54.760 --> 0:03:57.880 millimeters long, and they can fly up to twenty kilometers 0:03:58.040 --> 0:04:01.600 or twelve point four miles to find the right species 0:04:01.600 --> 0:04:04.880 of fig plant. When they arrive, they deposit their natal 0:04:04.880 --> 0:04:08.080 figs pollen, lay their eggs, and the whole process starts 0:04:08.120 --> 0:04:12.440 all over again. There are, however, two exceptions. About point 0:04:12.520 --> 0:04:15.960 three to five percent of the time, fig wasps don't 0:04:16.000 --> 0:04:19.800 collect the pollen they're supposed to, and the figs aren't pollinated. 0:04:20.040 --> 0:04:22.600 When this happens, the fig doesn't grow seeds and the 0:04:22.680 --> 0:04:26.680 tree may drop it. Any wasp offspring will die from 0:04:26.720 --> 0:04:30.720 the collision. Also, if a female wasp enters an already 0:04:30.880 --> 0:04:33.600 edible fig, she can't lay her eggs. Because of a 0:04:33.640 --> 0:04:37.479 long part of the flower called the stylus, she'll probably die, 0:04:37.880 --> 0:04:41.320 but at least she's delivered the pollen. An enzyme inside 0:04:41.360 --> 0:04:45.040 the fig called feistin breaks down her corpse into protein, 0:04:45.560 --> 0:04:48.320 ingesting the dead wasp and making it part of the 0:04:48.400 --> 0:04:51.760 ripe and fruit. So just so we're clear here, those 0:04:51.760 --> 0:04:54.719 crunchy bits that you're chewing on in figs, those aren't 0:04:54.720 --> 0:04:58.320 bits of dead wasp. There the fig seeds, and anyway, 0:04:58.600 --> 0:05:01.200 you should get used to the idea of occasionally eating 0:05:01.200 --> 0:05:05.600 an insect by accident. There in lots of agricultural products peanut, butter, 0:05:05.920 --> 0:05:12.800 canned corn, and even coffee can have insect bits in them. 0:05:12.880 --> 0:05:14.840 Check out the brain stuff channel on YouTube, and for 0:05:14.960 --> 0:05:17.359 more on this and thousands of other topics, visit how 0:05:17.400 --> 0:05:32.200 stuff works dot com.