The Secrets Of The Venus Flytrap
The Venus flytrap is one of the world’s most iconic plants, partially in thanks to the 1986 cult classic Little Shop of Horrors. But while we all know Venus flytraps don’t eat people, few people know that they rarely eat flies. They prefer ants and other insects that crawl helpfully into their traps. They’s also not a tropical species—they’re endemic to a small area of land in North and South Carolina, a region that’s being impacted by climate change.
And in our latest Macroscope video, researchers Elsa Youngsteadt and Laura Hamon are rushing to understand more about the Venus flytrap before it’s too late. Science Friday video producer Luke Groskin joins Ira to talk about what we know and don’t know about this famous carnivorous plant.
Luke Groskin is Science Friday’s video producer. He’s on a mission to make you love spiders and other odd creatures.
[MUSIC PLAYING] IRA FLATOW: That music means only one thing– it’s a special video coming up. Did you ever have a Venus flytrap as a kid? Yeah, I did. Don’t you think it– you know, didn’t you think it came out of a mysterious tropical island, right? Guess what? The flytraps are– they’re not tropical. They’re endemic to a tiny area of land in North and South Carolina, right here in the good old USA. No wonder I couldn’t keep mine alive– I lived in the wrong place!
And did you know that Venus flytraps, they rarely eat flies? They prefer ants and other things that crawl into their traps. But the most worrying fact of all is that Venus flytraps are being threatened by climate change and development where they live. And in our latest Macroscope video– that’s what the sounds were for– researchers are hurrying to figure out what else we don’t know about Venus flytraps before it’s too late.
Joining me now to talk about it is Science Friday video producer Luke Raskin. Welcome back.
LUKE RASKIN: Hi, Ira.
IRA FLATOW: From the land of the Venus flytrap.
LUKE RASKIN: Indeed indeed.
IRA FLATOW: So we don’t know that Venus flytrap plant as well as we think we do. What are some of the surprising things that you learned about them while you were going out there?
LUKE RASKIN: Well, the first thing that’s, to me, most surprising is that it has a flower. I mean, I’ve seen them in plenty of hothouses, but I’ve never actually noticed that they actually have a flower, because most people don’t grow them properly, so they don’t actually flower. So there’s this big, beautiful, bucolic white flower with a little yellow in the center.
So that was pretty amazing. Also, that they have multiple traps– that was pretty fascinating to learn about. And it was also fascinating to learn that they have– they grow in non-tropical areas, as you mentioned, and that they live in poor soil. So that was also fascinating to learn about. There’s a lot about these plants that we don’t know about. I mean, we know a lot about their traps– they’re well-studied. But the basic ecology, and what is the lifecycle of these plants, and how they reproduce– not a lot is known about it.
IRA FLATOW: And speaking of the flower, one of the things you showed is in beautiful video stuff of you flying– you swatch the– they’re not flies that get trapped in there, right? There are bugs that crawl in there.
LUKE RASKIN: No, it’s usually ants and spiders.
IRA FLATOW: Ants and spiders. Yeah, but then how does the flytrap avoid eating the animals that it needs to pollinate the plants?
LUKE RASKIN: So this is the big– I mean, there’s a question about its conservation. You can’t protect a plant without understanding how it reproduces. But then, there’s a bigger evolutionary question, which is, you have a carnivorous plant that eats insects. And it needs those same– that needs insects, also, to reproduce– to pollinate itself.
IRA FLATOW: Right.
LUKE RASKIN: It has very large pollen, and so it’s very unlikely that it’s going to pollinate itself. And so these researchers at the North Carolina State University, they’re studying, how does a plant, a carnivorous plant, get by? And they have a couple of theories. The first is that there’s a big distance between the traps and the flower. There’s about a foot, usually. And so most of the things that pollinate the plant are going to be flying bugs, like little sweat bees, and butterflies, and things like that, and the rest are all on the ground.
So there’s the distance. And then, there’s also– it could be the color. The plants are– the flowers are this bright white, and the plants, the traps, are this green with a little bit of hues of purple and red. And then, lastly, there’s the smell. And they’re studying that this past summer and in upcoming field seasons, where they put little cups in front of the flowers, and cups in front of the traps, and they actually try to collect the actual chemicals– volatile chemicals– coming out of them to see what induces– what could be inducing– different insects to come over and check it out.
And of course, you’re like, OK, this seems like a lot just to find out how a plant doesn’t eat its own pollinator. But if you really want to protect these plants– and they do need their pollinators– you’ve got to figure out how they reproduce.
IRA FLATOW: Talking with Luke Raskin and Science Friday from WNYC Studios, talking about his latest Macroscope video of these Venus flytraps. And we learned that they’re endangered, right?
LUKE RASKIN: Yeah.
IRA FLATOW: They only live in that part of the world? Who knew?
LUKE RASKIN: Well, yeah, exactly. Like you said at the top, that you would think it’s a tropical species– it’s not a tropical species.
IRA FLATOW: Yeah.
LUKE RASKIN: There’s only a tiny, tiny section of North Carolina– a little bit of South Carolina, as well– where these plants live. And so they require– they have very specific environmental requirements. So they need a lot of fire. The fire burns away the taller shrubs and the grasses so that the plant can get sunlight. And if you have a lot of development going on, you probably don’t want a lot of fire going on. So there’s that problem.
And then, there’s this other problem where people are actually going out there at night, and collecting them by the hundreds, and selling them on the black market. So yeah, there’s a black market for flytraps.
IRA FLATOW: Poaching.
LUKE RASKIN: Yes, there’s poachers.
IRA FLATOW: It’s like, they’re not orchids, they’re flytraps. Wow.
LUKE RASKIN: Yeah, and it is actually a crime in North Carolina to actually– to go out and take these, with some serious penalties. And there’s been several cases in the past five years where people have been caught, and they’re facing jail time.
So yeah, these people are going out and taking them, and if you take a hundred or several hundred of these plants from an area, and they only live in a small area, and there’s not that many of them, you are making a significant hit on the population. So, yeah, the black market trade of flytraps is real.
IRA FLATOW: So you’ve got to be careful, if you buy one at a store, that it’s not poached.
LUKE RASKIN: Yeah, I mean, if you go to a greenhouse and you see one of these plants, find out where it came from. Just ask, like, where do you get it from? There are not many distributors of flytraps in the world, and most of them are not getting their fly traps from North Carolina, from where they’re found. So just ask.
IRA FLATOW: Just– yeah.
LUKE RASKIN: Yeah, it’s not hard information to find out.
IRA FLATOW: Thank you, Luke.
LUKE RASKIN: Thank you.
IRA FLATOW: Luke Raskin, it’s a wonderful Macroscope video. It’s up on our website. It’s sciencefriday.com.
One last thing before we go. 28 years ago today, November 8, 1991, the first episode of Science Friday aired. Can you believe it? We’re entering our 29th year. And one of our first guests was the late Sherwood Rowland, who explained the phenomenon of how chlorofluorocarbons– CFCs– from spray cans were creating a hole in the ozone.
SHERWOOD ROWLAND: What they do do is go up into the atmosphere, up into the stratosphere, above most of the ozone layer. And when they get above most of the ozone layer, they can absorb short-wavelength ultraviolet radiation from the sun. What this does is release chlorine atoms. Chlorofluorocarbons contain chlorine, fluorine, and carbon. And when they release the chlorine atoms, a long chain reaction in which each chlorine atom can take out 100,000 molecules of ozone ensues.
IRA FLATOW: Dr. Sherry Roland later went on to share the Nobel Prize in Chemistry for that work. So as we enter our 29th year, we plan to bringing you even more of the same important research, big thinkers, with plenty of time for whimsy, curiosity, and discovery, too. Thank you for listening to all these years.