The Venus Flytrap and Other Carnivorous Plants
https://archives.nbclearn.com/portal/site/k-12/browse/?cuecard=40263
General Information
Source:
Creator:
NBC Today Show
Gene Shalit
Resource Type:
Copyright:
Event Date:
Air/Publish Date:
03/21/1977
03/21/1977
Copyright Date:
Clip Length
Video News Report
NBCUniversal Media,
LLC.
1977
00:10:59
Description
Biologist Allan Swenson describes and demonstrates how a Venus flytrap and other insect-eating plants
capture and digest flies and other insects.
Keywords
Venus Flytrap, Plants, Carnivorous Plants, Prey-Trapping Plants, Sundews, Drosera, Purple Pitcher Plant,
Flies, Insects, Bugs, Housefly, Fruit Fly, Mosquito, Gnat, Roach, Cockroach, Aroma, Scent, Insect
Attractant, Trap, Trigger Hairs, Snap, Close, Pocket, Airtight, Digest, Digestion, Enzymes, Protein,
Breakdown, Nitrogen, Nutrients, Husk, Tentacles, Secrete, Secretion, Spine-Lined Mouth, Food Storage,
Roots, Bulb, Bulb Plant, Photosynthesis, Moisture, Mucilage, Hydraulics, Humidity, Boggy Soil, Bogs,
Swamp, Moss, Sphagnum Moss, Soil, Nutrient-Deficient Soil, Habitat, Terrarium, House Pete, Show and
Tell, Science Fair, Science Supply Company, Allan A. Swenson, "Cultivating Carnivorous Plants",
"Insectivorous Plants", Charles Darwin, Amazon, Brazil, Adaptation, Biology
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Page 1 of 5
Citation
MLA
"The Venus Flytrap and Other Carnivorous Plants." Gene Shalit, correspondent. NBC Today Show.
NBCUniversal Media. 21 Mar. 1977. NBC Learn. Web. 20 March 2015
APA
Shalit, G. (Reporter). 1977, March 21. The Venus Flytrap and Other Carnivorous Plants. [Television
series episode]. NBC Today Show. Retrieved from https://archives.nbclearn.com/portal/site/k12/browse/?cuecard=40263
CHICAGO MANUAL OF STYLE
"The Venus Flytrap and Other Carnivorous Plants" NBC Today Show, New York, NY: NBC Universal,
03/21/1977. Accessed Fri Mar 20 2015 from NBC Learn: https://archives.nbclearn.com/portal/site/k12/browse/?cuecard=40263
Transcript
The Venus Flytrap and Other Carnivorous Plants
GENE SHALIT, reporting:
Have you ever sat down to dinner ready to bite an asparagus and worry that the asparagus might bite you
back? Of course not, asparagus has been tamed, it wouldn’t hurt a fly. You cannot say that however about
the Venus flytrap, a crafty plant that dines on houseflies, fruit flies, and all sorts of tiny winged beasties
that dine out. These plants are carnivorous, and Allan Swenson knows so much about them that he has
produced a book telling you how to raise carnivorous plants in your very own home. It’s called
“Cultivating Carnivorous Plants”, and this morning he’s going to show us some. Good Morning, Allan
Swenson.
ALLAN SWENSON (“Cultivating Carnivorous Plants”): Howdy, howdy.
SHALIT: These plants really eat bugs and things?
SWENSON: Oh they do indeed. I’ve traveled the world looking for them all over the place. In fact twenty
years worth of my life, chasing these little things to the Mountains of Moria and to the Brazilian jungles,
I’ve got a little Brazilian sun doing here. But people probably know most about this, the Venus flytrap.
This little thing catches insects beautifully. It’s got a trigger mechanism just like your hands. And you,
just assume there are three trigger hairs on your hands, it opens up cocked like this.
SHALIT: Can I go like that, I’m the fly.
SWENSON: You touch one,
SHALIT: Yea.
SWENSON: Nothing happens. You touch two and it’ll snap like this, and then it’ll slowly close up as the
© 2008-2015 NBCUniversal Media, LLC. All Rights Reserved.
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fly struggles, and digest it with enzymes. So why don’t we try just to take a little fly.
SHALIT: We have a real fly, folks.
SWENSON: While I was chasing him around, I hit him on the head a little bit. And let’s see how we do
with this little fellow here. Now these have been bouncing around an airplane, so I’m not sure they’re
going, whoop!
SHALIT: Oh my god he’s going to eat your tweezers.
SWENSON: There he has it.
SHALIT: How fast did that close?
SWENSON: Well, a good trap with plenty of moisture will snap at about a twentieth of a second. And
they, they’re quite lethal on the flies, insects and mosquitoes. They make great pets too because you don’t
have to feed them, and they don’t have to be sprayed to get rid of insects, they catch the insects and they
use them for food.
SHALIT: Now wait, you’re going to fast for me.
SWENSON: Oh.
SHALIT: There’s a live fly, goes in there, why does he go in there in the first place, is he inquisitive or
what?
SWENSON: Aroma and scent of the plant, it gives out an insect attractant and the fly goes in and lands to
see what’s going on.
SHALIT: Okay, now the fly lands in there and this guy closes in a twentieth of a second.
SWENSON: Right.
SHALIT: When the fly lands, is he in any way immobilized, is there any poison or something in there,
SWENSON: No.
SHALIT: That makes him unable to fly out again?
SWENSON: He’s just caught by these little fingers on the edge of the leaf. And they hold him in there
and he struggles. Now we have, I brought along some slides I took while I was taking for the book.
SHALIT: Okay. Slide.
SWENSON: Now this will show you the open trap with, you can barely see the three little trigger hairs on
the trap. And then once it snaps, like we just showed you, you can see the next picture will give you an
idea of what the, little insect trying to get out of the flytrap, as it struggles a little bit more, it finally makes
an airtight pocket, then the enzymes do the digesting, they break down the protein of the insect and that’s
how they get their nitrogen, their nutrients to grow.
SHALIT: Okay, so the fly’s in there and the fly is digested by enzymes in the plant. Is the entire fly
consumed in two days, how long does that process take?
SWENSON: Four or five days, and then,
SHALIT: Four or five days, if I opened up the plant will I see any fly in there?
SWENSON: You will see the husk, what remains, the hard part of it. They couldn’t actually eat a roach or
something hard because it’s just too crisp for them, gives them indigestion.
SHALIT: Now what do they do with the, with the husk of the fly? They go,
SWENSON: It’ll normally wash out when you’re watering it, or it’ll blow away, or you can just scoop it
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out a little later on. They keep growing more from the bulb and you’ll have some traps will get two, three
inches long perhaps, I’ve seen them not quite three inches but a good size trap after the plant’s been
growing for awhile.
SHALIT: Now Allan if you had ten of these in a home, would that keep your home fly free?
SWENSON: Actually not Gene, because they do attract more insects. And once they close, the attraction
is still there.
SHALIT: In other words, they attract more flies than they can eat?
SWENSON: More or less.
SHALIT: They’re greedy.
SWENSON: Yes. They do indeed.
SHALIT: So there’s a lot of leftovers flying around your house.
SWENSON: They do even in the wintertime, you know you’ll bring in some fruit and vegetables, and
you’ll find little fruit flies come in, because they’re very small you won’t catch them in the flytrap too
well, but we have other types. Now this, this little one here, these the sun use.
SHALIT: Which are? Right here?
SWENSON: These little ones in here.
SHALIT: Okay.
SWENSON: They’re very nice for terrarium plants, they get bright red in the sun, and they wrap tentacles
around an insect.
SHALIT: Can we put that out here,
SWENSON: Sure.
SHALIT: So we can really see this?
SWENSON: I think we can.
SHALIT: Let’s just, that’s it right there. Now these are sundews.
SWENSON: Those are sundews right there, right here.
SHALIT: And those are tiny.
SWENSON: They’re tiny.
SHALIT: Now what can they catch?
SWENSON: Well the next slide will show you what they can catch. Because they’ve got good capacity to
grab a little insect, and as the insect struggles it wraps its tentacles right around it, and the little juices are
secreted with the enzymes in them, and that’ll catch the fruit flies, the little gnats, and the mosquitoes.
SHALIT: Now, I have to ask you a question. All the plants with which most people are familiar live on
sunlight and water and so forth. Now how did such a plant come into being, why did it need to go after
meat?
SWENSON: Well many people that I’ve talked to around the world, while I’ve been studying these, there
are about four hundred types of carnivorous plants, and they have the wrapping technique, the snapping
technique. This little one has a spine-lined mouth.
SHALIT: What’s it called?
SWENSON: This is called a purple pitcher plant.
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SHALIT: Purple pitcher plant.
SWENSON: It has hollow pitchers, and all the carnivorous plants grow in the boggy soils or swamps that
are very deficient in plant food or nutrients. So they’ve adapted over the years just as Charles Darwin
described in his book, in fact he even wrote a book called “Insectivorous Plants.” But this one, to get its
nutrient when it has none in the soil, it has a spine lined mouth and the spines all point downward. The
bug gets attracted and smells something good and goes flying around, buzzes in here and starts to walk
down. Well, then it gets a little smart, it says aha, I’m in trouble. Turns around but the spines point the
wrong way, so it pushes against the spines and the spines flip it back into the soup. And the soupy broth in
here, liquid that’s pulled up with the enzymes in it in the hollow pitcher, and that digests the insect for the
meal for the plant.
SHALIT: Since most of my friends don’t live in the bogs of Brazil, they are going to have to buy plants
like this if just for fun they decide they would like to have as a house pet, a carnivorous plant. Now, what
will urban dwellers do for food for a Venus flytrap in the wintertime when there are very few flies
around?
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