From the Vault: Carnivorous Plants

Are humans truly safe from the hunger of meat-eating plants? Can we trust the trees that loom over us? In this episode of Stuff to Blow Your Mind, Robert and Joe discuss myths and fictions of killer trees, the science of carnivorous plants and the curious absence of mean-eating plants in our natural world. (Originally published October 18, 2016)

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Episode Transcript

Speaker 1 (00:05):
Hey, you welcome to stuff to blow your mind. My
name is Robert Lamb and I'm Joe McCormick. And it
is Saturday. The vault hangs open, and it is a
October vault. Isn't that right, Robert? That's right. That is
why the vault is full of monstrous, curling, twisting vines.
This week. Vines. They just want to grab hold of

(00:26):
you and just drag you down into the carnivorous undergrowth.
This was an episode published originally on October eighteen about
carnivorous plants and uh, and so we hope you will
stay around for the Tree of Terror. Yeah, imagine there's
gonna be a little bit of a little shop of
horrors in this one. Maybe I think we remember everything
we referenced. We talked about that what's that um William

(00:49):
Friedkin movie with like the killer Enchanted Tree, Killer Enchanted Tree.
Oh well, we talked about in the spoil it for you.
I've already forgotten what it is and now I'm gonna
have to look it back up because that's sounds amazing. Okay,
without any further ado, let's just jump right into it,
back into the vault, back into the embrace of the Vines.

(01:12):
Welcome to Stuff to Blow your Mind from how Stuff
Works dot com. Hey, welcome to Stuff to Blow your Mind.
My name is Robert Lamb and I'm Joe McCormick and Robert.
I want to put you in a scenario a bit seasonal.
Oh yeah, that's a seasonal Halloween scenario. Do you do

(01:33):
you want to go with me on a hike high? Alright,
it's late October and you are on a solitary fall
hike through the woods, and the leaves are starting to
turn orange and red. The air is dry, and you
feel like an adventure, so you head off trail. Not
always a good idea, but let's just say you're brave.
If this is how all terrible stories start, how all

(01:55):
tragedies begin, you leave the trail, Well, it starts very nice.
So you're off trail and you find a little mountain
brook and it's twisting among the rocks, and you decide, oh,
how sweet, I'm gonna follow this upstream, maybe I'll find
its source. And on the way you come across a
cluster of what looked like oak trees, thick trunks with
roots spread out exposed over the bank of the brook,

(02:18):
and there's an odd smell. It's a little bit sweet
with just a hint of deep earthiness, kind of like
overripe fruit. So you approach the stand of trees and
the ground is covered with a mat of these beautifully
colored fallen leaves. And as you come near the trunk
of the nearest tree, your foot knocks against a smooth

(02:38):
stone tangled in the outer roots. But wait a second,
that's no stone. It's smooth and white, partially buried with
two eye shaped hollows. And then suddenly, with a rushing
sound and a scattering of leaves up into the air,
something envelopes you. The light gets blotted out. You feel
these wooden fibers pressing into your skin from all sides.

(03:01):
What's going on? You struggle to free yourself, but you
find that you're becoming sluggish, disoriented. There's a powerful smell,
your throat burns, and then the digestive enzymes come. Another
visitor disappears into the grove of the killer tree. Ah.
I knew it was a killer tree once the digestive

(03:22):
enzymes in the woods started happening, because my first instinct
would be, oh, something was in the tree. I got
myself tangled and then something was in the tree and
it jumped down upon me, some sort of predator of
some sort. I guess that's the more logical thing to think, right, Yeah,
at list until the wood comes, or that somebody has
set some kind of trap for you. This is a
human design, That's probably what I would guess. But Robert,

(03:44):
what first comes to your mind when I say killer tree?
I'm sure you've got like a fictional anchor point that
you go to. Oh, I mean there's so many, uh,
there's so many examples of killer trees, and especially in fantasy, right,
I mean it makes you think of the ants or
especially like the dark sort of tree people from Dungeons
and Dragons. I'm not really familiar with those. Well, what

(04:06):
happens when you fight a tree person? Well, you know,
they're big, they're wooden, they're they're lumbering. I think there
are a few a few different varieties. There's they're basically,
you know, they're animate trees, and then they're sort of
wooden people, and they're good and good ones and they're
bad ones. Of course, the ants that we encounter and
the Lord of the Rings are are are good. So
when you're battling a tree person do you like, do

(04:28):
you have to have a paladin with a blessed wood
chipper or something. I don't recall there being a requirement
for magical weapons. Of course, you know, some creatures can
only be fought with natural weapons, but with the with
magical weapons. But I believe that the tree creatures in
this case are just big, tough trees, because that's the
thing they're they're they're they're large, They're flesh is different

(04:50):
than us. So the idea of them becoming animate, the
idea of them turning against us is terrifying. Uh, and
they do turn against us. I mean, we live in
a very um uh tree friendly city. So anytime the
wind blows, anytime the anytime the rain freezes, the trees
rattle and threaten us. When they fall, they can cause

(05:11):
significant damage and even loss of life. There is a
killer tree hanging over our house right now. Rachel and
I are working on getting something done about that. But yeah,
it's this old dead pecan tree. It just looks like
it is aching to plunge its killer branches through somebody's roof.
And so yeah, there, of course killer trees in reality,
but the kind we're thinking of are the ones that

(05:33):
are a little more conscious with some directed actions the agency,
maybe some arms, some tentacles, some some gaping maws with
thorn teeth. Of course one of the big ones, and
this one entered my mind when you were taking me
through descriptions. Of course, in poulter Geist, there's that just
horrifying scene that scarred me from an early age, where
you have you have multiple things going on it once,

(05:54):
like there's the creepy clown um doll on the bed,
but then there's the tree outside the window. It's like
trying to eat the child man. So I haven't seen
Poulder guys in years. I honestly don't remember this scene.
I guess I gotta go back to one of many.
They throw a lot of nightmare imagree up against the
wall and up up their amount of it sticks. So
I gotta tell you that this episode. I wanted to

(06:16):
do this topic because I was inspired by having recently
watched the William Friedkin horror movie The Guardian from nineteen
for the first time. I remember the trailer for this
is like a creepy babysitter, creepy nanny, but I never
saw it, so I don't know what the what the
gimmick is. Well, I'll give you the premise. It's about
a couple who has a baby and they're looking for

(06:37):
a nanny because they both want to go right back
to work immediately, so they're looking for a nanny to
take care of their child, and they end up going
with Camilla, the British nanny, who unfortunately is a druid
who has got a tree friend, and her tree friend
is a killer tree friend, and she likes to take
babies to the tree sacrifice them to the tree. Except
it's this weird thing where the tree sort of observe

(07:00):
orbs the baby, and then you can see the baby's
face embedded in the surface of the tree. So I
guess that the baby kind of melts into the tree
and becomes petrified. Anyway, she she's an evil druid, kidnaps babies,
sacrifices them to a killer tree. There are scenes where
the tree kills people. There's like Camilla gets attacked in
the woods by some by some creeps who just happened
to be hanging out in the woods, and the tree

(07:21):
defends her by essentially smashing them and tearing them up.
So would you say this is part of the Druids ploitation,
uh movement of the nineties. Man, if only there were
such a genre, I would be all over that. I
would be like a film scholar of the genre. But anyway,
so do I recommend this movie. It's not a good movie,
but it's William Friedkin, so it's like a well made

(07:43):
bad movie, if that makes any sense. He there's a
there's a certain segment of his filmography that that definitely fits.
That always worth checking out if you're a fan of his.
But you know, maybe not Tough Shell. I guess I'd
say it's not good, but it's worth seeing, especially since
the spoiler alert the client max of the film involves
a chainsaw. Oh well, of course it would. Um, of course,

(08:04):
there are plenty of other cinematic examples of animate trees,
murdering trees, and just murderous plants. Um. Aside from ants,
there's the I don't know if anyone remembers the sexy
Matron tree from the Last Unicorn. The tree becomes animate
and attempts to love our hero to death, or one

(08:25):
of our two heroes, the male hero s Medric I believe,
and uh this sounds troubling. Yeah, she has like huge
bosoms and all um weird, it's a it's a weird
It's a weird film when you look back on it.
Lots of strange elements. Uh. Scott Smith's novel The Ruins
and the two movie adaptation of it, the concerns man
eating vines. Yeah, and they're sort of infectious, right, So

(08:48):
it's not just that the vines reach out and grab you,
but that there's a spore element where they contaminate you
with some kind of plant germ cell. I think so, yeah, yeah,
which is interesting when you start getting into some of
the the technical possibilities of man eating plants. Um, let's
say already mentioned Poulter guys. There, of course the vines
and evil dead that are rather notorious. There are some

(09:10):
man eating plant action in Chinese Ghost Story, which I
have not seen yet. After reading a synopsis of part
of it yesterday, it's moved back up to the top
of mine must watch list. You got the whamping Willow
and Harry Potter, you have you have a version of
the the evil dead vines that are mentioned in A

(09:30):
Cabin in the Woods. They quote angry molesting tree, which
I think you only see like a a just a
fragment of it as it like snatches a guard in
one scene. Man Cabin in the Woods is full of
just great little freeze frame moments. Oh yeah, tremendous. Uh.
They're various kaiju that, you know, giant monsters that have

(09:51):
had plant elements to them and certainly planning with fun
guy elements to them. And I believe one of Michael
Shay's Niffed stories features a carnivorous plant kind of like
a venus fly traffic suchet has a like a humanoid
female part in the middle to lure males inside it. Weird,
but I don't have a clear memory of that, so
maybe I'm imagining it, but it seems like the kind

(10:13):
of thing that would be in one of his stories. Now,
almost all of these seem like modern fictional inventions. Do
are there? Are there animated trees, animated predatory trees or plants?
Going back in mythology, I would expect to find such
a thing. I expected to find some better examples, and
I was not able to find any. Um, not to

(10:35):
say that I didn't miss something, But the closest, the
closest example that I came across, and I got excited
about this was is that is this example of something
called a jidra uh and this is from the traditions
and folk beliefs of the Middle East. But here's the
caveat as related by medieval European travelers. And this is

(10:55):
a theme we're going to see time and time again.
The plants become animate and man killing only in foreign
environments entered by westerners, right, European and American travel writers
and cataloguers of things going on in places other than Europe,
in America and the America's talk about man eating plants,

(11:16):
right and in this case as again as related by
medieval European travelers, and this was explained by Carol Rose
and are always excellent giants, monsters and dragons Encyclopedia. Uh.
The idea is this thing emerges from the ground like
a plant, and and it's rooted in place, and it
just consumes anything in its vicinity, you know, cattle, small animals,

(11:37):
and of course humans. The only way to kill it
is to detach it from its root, essentially chop it down.
And if you do, then you get to harvest its bones,
because I guess it has bones which would be valuable. Um.
It has bones. Apparently that's according to the myth. So
I don't know if this means that it literally has
bones and it's a like a rooted mammal creature vertebrate
creature of some sort, or if bones and by bones

(12:00):
we mean it's like it's it's would you know, you
know that does sound valuable because you could probably use
the bones of the Jidra to make a totally vegan stock, right,
so you roast the bones and then make it make
like you'd make a chicken stock or something, but this
would be vegan, I said, depending, well, depending on exactly
how you classify a monster like this. Now, I should
also add that it's thought that this myth probably also

(12:22):
derived from the man Drake, So you know, European influence
the idea of the man Drake, which is this kind
of like animal um vegetable hybrid creature, and then this
kind of evolves into this tail of the j dra okay,
And I find it curious, though, you know, I looked
around for more examples, couldn't find it. I would have

(12:43):
expected plenty of the Elder, the noted first century Roman
historian who often spoke of foreign monstrosities, to have like
a clear cut example of a man eating plant in
foreign land. Oh yeah, plenty of the elders like the internet, right,
like if you can think it up, it's on there,
and if you can imagine it, plenty road about it. Yeah,
like people like beast people in other lands, the people

(13:04):
with the bellies, the with head it had nowls in them.
I mean all sorts of strange humanoid monstrosities, beastly monstrosities, dragons, etcetera.
So why no man eating plants? I don't know. Now, Robert,
did you ever see him? Night shamelans the happening. I
did not. I saw the trader. It happened. There was
some happening, and it happened, and it was about trees

(13:25):
that were trying to kill Mark Wahlberg. I have no
idea why they want to do that. But it wasn't
really predatory behavior. It was more like vindictive jerk behavior.
So the trees didn't want to eat us. They were
like tired of us being abusive to them. So it's
even less uh in less biologically sound, yes, than than
any of the examples we've looked at this far. So yeah,

(13:46):
obviously this idea of the killer tree, the man eating
plant is one that captures our imagination very easily. And
I think I've got a theory as to while, and
let me know what you think of this. I think
the reason we like the image of the killer tree
and it shows up in all these stories reas, is
because the idea of a man eating plant has a
certain level of why not to it? Right? So, there

(14:07):
are creatures in nature that kill large animals with claws
and teeth and tentacles and venom and such, and plants
have things that are equivalent to this. They've got thorns, vine, tendrils, poisons.
Trees are much larger than us, and in one sense
they are apt to be much quote stronger than any
animal prey that would try to resist them. So why not,

(14:29):
you know, if the continent of Australia can produce an
animal that has the fur of a mammal in the
bill of a duck, why couldn't some deep, unexplored forest
harbor a tree that can reach out with a vine
covered in venomous thorns and snatch a hiker, wrap him up,
roll tight until he turns blue, and then pull him
down into a crevice in the root structure and treat
him like a soft salty meal. Yeah, I agree, I

(14:52):
think on on on one hand, certainly, we look at
all the variety of nature, we see what's possible within nature,
and you ask yourself, we'll wind a in this exists.
Maybe it does exist. Maybe some you know, a third
or fourth hand tail that I've heard about a man
eating plant is from a traveler is actually true. And
on the other hand, I think the reason it's so
appealing is because it's abhorrent, the idea it's crossing category

(15:16):
exactly inherent taboo. Yeah, because I find myself kind of
like if I see an example of an insect preying
on a on a vertebrate, like invertebrates eating vertebrates, something
that kind of like it's wrong, has got a frog
in its web. Yeah, it's like that. You're not supposed
to move in that direction because stick to your your

(15:36):
own invertebrate kind. But of course it happens. Now, of
course I wouldn't actually blame the spider for that. I
think that's perfectly fine. But no, no, no, no, no
judgments spiders. But but from our human standpoints, even more important,
because we've largely removed ourselves from the risk of fredation
like which is a pretty remarkable thing in the grand

(15:56):
scheme of things, right, and so we don't have to
worry about other animals eating us. And the idea of
another animal eating us is strange and awful and terrifying.
Even more so the idea that a tree could do it. Yeah, yeah,
I totally see. It goes backwards on the chain, the
food chain, right, it's reversing the food chain. That's it's
not supposed to be this way. So, except for the

(16:18):
fact that we've never seen things like this happened, at
an intuitive level, it's like, what's so implausible about it? Uh?
Then at the same time, I think we may be
able to come up with some good biological reasons we
don't actually see organisms like this. But according to some
we must say, not very credible accounts, there is nothing
all that implausible about the man eating tree, the killer tree,

(16:41):
because people have written about these things as if they
actually exist within the past few hundred years, and that
hearsay was more more powerful previous times exactly. So I
want to talk about one source, a very weird biology
book from the eighteen eighties called Sea and Land, written
by a guy named James William Buell. Now, just glancing

(17:02):
through this thing and looking at the author's introduction, it
is obvious that this is not a source of credible
scientific information. It's more one of those nineteenth century natural
Wonders books. You've ever seen these kind of things, where
there you know, like, wow, look at all these illustrations
of animals in their natural habitats. But they're all grossly inaccurate,
and it's really not all that different from various versions

(17:24):
of Plenty's work from previous times, exactly, except it's you know,
eighteen hundred years later, however, whenever Plenty was living, Yeah,
exactly so, but it's got all these allegations of weird
sensational creatures mingled in with reports about real animals, and
I have to also say, like a very Eurocentric sense
of exoticism about the planet. So there's that kind of

(17:45):
unsavory element to it. But it's also full of gruesome
and probably highly inaccurate illustrations about various animals and attack modes.
Some of these illustrations are great. There's a good one
of an orangutang apparently kicking a man to death, one
of a swordfish stabbing at a sailor through the hull
of a boat. Not impossible, extremely rare. But as we've

(18:06):
discussed in our Jumping Fish episode, it it has happened, okay,
or well, individuals have been stabbed, boats have been stabbed.
I don't know if anyone, I don't I don't remember,
of both happen, it would be really bad luck. Yeah,
but yeah, in this case, it looks like the swordfish
is trying to kill the guy. Okay, but in any case,
there's another one that's awesome. It's a giant crab hanging
from a tree, lifting a goat up into the tree

(18:28):
with its claw as if to devour it. But then
finally a tree with tentacles pulling a human victim into
the crown of its trunk. I have to say these
different accounts here. I couldn't help but think of a
Simpson episode, and I don't even remember the context, but
there being a scene where like a gorilla is in
a tree and a shark comes out of the river

(18:50):
underneath it and eats the gorilla as an example of
like natural predation or something. Oh wow, But yeah, So anyway,
so you Will says that travelers have told him stories
of a carnivorous plant that grows in Central Africa and
South America. And he says it's so voracious it even
resorts to eating humans. And I want to read a

(19:11):
quote from the book. He says, quote. This marvelous vegetable
minotaur is represented as having a short, thick trunk, from
the top of which radiate giant spines, narrow and flexible,
but of extraordinary tenaciousness, the edges of which are armed
with barbs or dagger like teeth. Instead of growing upright

(19:31):
or at an inclined angle from the trunk, these spines
lay their outer ends upon the ground, and so gracefully
are they distributed that the trunk resembles an easy couch
with green drapery around it. Uh. Then he goes on
to say that the unfortunate traveler will come along and
quote the moment his feet are set within the circle
of horrid spines, they rise up like gigantic serpents and

(19:55):
entwine themselves about him until he is drawn upon the stump,
when they speedily dry of their daggers into his body
and thus complete the massacre. The body is crushed until
every drop of blood is squeezed out of it, and
becomes absorbed again by the gore loving plant when the
dry carcass is thrown out and the horrid trap is

(20:15):
set again. I'm some elements of that sound reasonable, especially
later when we get into real world carnivorous plants and
the idea that plants are living things that that live
and move at an entirely different speed. And therefore when
you see like fast moving actions such as from a
venus fly trap, it is very much like a like

(20:38):
a crossbow, a heavy crossbow that has been painstakingly loaded
over time and then sprung. So I could I could
see this idea of like a sprung trap working within
the conceivably working within the confines of of of actual botany. Yeah. Yeah,
with a certain type of movement, you can imagine it.
Less so when especially with something we're going to hear

(20:58):
about in the second though. I also want to add
a funny note that, in contrast to the passage I
just read that in the introduction, Bull says his purpose
in writing the book is to quote bring us into
a closer relation with and a better understanding and appreciation
of the mysterious and infinite wisdom of Nature's God. I
mean that certainly sounds like a devil created tree. There

(21:22):
ever is such a thing. But anyway, um so Bull
says that a gentleman of his acquaintance who lived sometime
in Central America affirms the existence of a plant like
this there, except was with a few variations. So he
says that instead of lying on the ground, the filaments
of the plant quote moved themselves constantly in the air,
like so many huge serpents in an angry discussion, occasionally

(21:46):
darting from side to side as if striking at an
imaginary foe. Now that sounds completely That sounds like not
a plant. Yeah, I mean the closest thing I can
think of that is, say, like a pussy willow with
with the wind blowing through it, you know, right. But anyway,
He goes on to describe how this tree would crush
its prey and an embrace of spines, and he compares
it to the method of execution from alleged medieval torture

(22:08):
dungeons known as the iron Maiden. He also claims that
in some regions, the locals are said to punish criminals
by casting them into the tree, which is, to anybody
practicing witchcraft, you go straight into the tree, and that
the plant is known as yatte vo Spanish for I
see you. Though I double checked the translation, Apparently it
has a tensed inflection really meaning I already see you,

(22:31):
which is even a little creepier. I do like that
a and almost certainly non existent man eating plant. The
comparison is made to the almost certainly non existent, at
least functional and functional terms iron maiden. Yeah, yeah, that
that is the case, right. Like I've heard, there's no
good evidence that iron maidens were actually used. That is

(22:51):
my understanding. That they became kind of you know, they
became it. They were an invention and then took on
a new life. Is kind of a fetish, I him
for those that wish to possess tortuous objects. Weird anyway.
I hate to be a downer, but I think we
can be pretty certain that this is all a bunch
of nonsense. Like this, this just sounds like complete fabrication.

(23:14):
There may be maybe or maybe massive, massive exaggerations of
something people actually saw that was in reality nothing like
what's being described. There are no trees with killer squid
tentacles that we know of, and I don't even I
think we can just say there are no such trees,
because it doesn't make any biological sense to have trees
with writhing tentacles that move around constantly. Yeah. The closest

(23:37):
thing I can think after this would it would be
the fact that, yes, vines grow on the ground, and
you could trip over a vine, you're like becoming tangled,
and you could hit your head on a rock or yeah,
sort of passive entrapment. That makes more sense, but hardly
a scenario that that I could see plants evolving to
utilize as part of their you know, their primary survival

(23:57):
um tactic. Right. But we will talk about the biological
possibilities of such a you know, mega fauna eating plant
later on in this episode. But we should say that
the yata Vo and and Bules accounts here are not
the only supposedly true accounts, or at least presented as
true by the by the recounters of of these man

(24:19):
eating plants or these giant killer trees. Yeah, and these
next two examples, like our previous two examples, are exotic
trees and a foreign land as experienced or at least
related by Westerners. So there's the Madagascar tree. And this
was something of a sensation at the time appearing in
publications of the seventies. The idea here was that you

(24:41):
had Western missionaries led by a German explorer called Carl Leachy,
and they accounted a tribe of cave dwelling tribespeople in
Madagascar who made sacrifices to a man eating plant um.
There's a fun quote from this so where they talk
about the atrocious cannibal that had been so inert and

(25:02):
dead came to sudden savage life. The slender, delicate palpy
with the fury of starved serpents, quivered at the moment
over her head. Then, as if instinct with demonic intelligence,
fastened upon her in sudden coils round and round her
neck and arms. Then, while her awful screams and yet
more awful laughter, rose wildly to be instantly strangled down

(25:24):
again into a gurgling moon, the tendrils, one after another,
like great green serpents, with brutal energy and infernal rapidity,
rose retracted themselves and wrapped her about in fold after fold,
ever tightening with cruel swiftness and savage tenacity of anaconda's
fastening upon their prey were well and whoever wrote it,

(25:48):
because that's one tremendous run on sentence. I love it.
It's true you can't stop for a breath. That that
is obviously some sensational detail. That does not sound like
like an account intending on clinical accuracy. Yeah, I I
do not buy it for second. So though some people
have the plant has achieved something of cryptid status. Even

(26:08):
the governor of Michigan, Chase Osborne, claimed that it was legit,
but no evidence has ever been presented, and it seems
to have been a little more than a literary fabrication. Yeah.
That just seems like another one of those kind of
like Eurocentric stories of the exotic weirdness of other lands. Yeah,
I mean another example, and I'm not going to go
into the jail on this one. But Phil Robinson, in

(26:30):
one writing in Under the Punka described tales of man
eating trees in southern Egypt, and this one is called
the Nubian tree. Um. Yeah, I all these accounts, they
really they have this sort of ickiness to it of, oh, well,
a Westerner being. Westerners live in a special land where
trees know their place, and we're we're above even predation

(26:52):
by by other vertebrates. But but it's like everybody wants
these things to exist, Like you can't stand the idea
that they're not real. You just don't want them to
be near you. They're they're hidden in some other place
where you don't live, a savage land full of savage people,
according to these recounters. Yeah, yeah, And I'm not trying
to say that that's like the the only element at

(27:13):
play here. I mean also, just like the idea of
man eating plants is really cool. I don't want to
suggest that the desire to encounter a man eating tree
is necessarily linked to some kind of colonial xenophobia, right,
but but I feel like there are some elements there
that are that are little key to to modern readers.
All Right, well, you know, on that note, let's take

(27:33):
a quick break, and when we come back, we will
we will ask the question, indeed, a question that the
Glenn Danzig may have asked, Uh, why do plants kill?
All right, we're back. Tell me, Joe, why do why
do the plants kill? Well, that is a good question

(27:54):
because in the realm of the well known, of course,
there are plants that kill. Right, So we've been talking
about trees that prey on humans in in these legendary accounts,
that are pretty obviously false. But there are plants that
kill not just with defensive toxins and thorns, but with
predatory tactics. They've got specially designed morphological features to trap, poison, paralyzed, dissolve,

(28:17):
and digest prey animals, generally insects. These are the predatory flora,
if you will, the eaters. So let's discuss a few
scientific facts about the eaters. First, I think we should
ask the question why would a plant kill to eat?
I mean, think about it for a second. A defining
feature of what makes a plant the plant kingdom is

(28:40):
the fact that plants, unlike us, are autotrophs. They make
their own food, so the energy that they need to
survive they get from photosynthesis. There's energy and the sunlight
coming down from the sky, and they use that energy
from pure sunlight to create a chemical reaction where they
react carbon dioxide from the air and water in the

(29:00):
end producing chemical energy in the form of glucose sugars.
I mean, when you look at the the energy economy
of life on Earth, generally speaking, plants are the only
ones with a with an ethical get out of jail
free card, right like well, I mean, I guess you
also microorganisms that ar tropes. But yeah, but but everything
else is having to consume something else for its energy,

(29:21):
has to steal its energy. But here we have all
these plants getting the energy from the sun. Well, it
seems cut and dry. I wouldn't let him off the
hook too much for the for the ethical quandaries, because
plants and will not necessarily plants, but auto trophes did
some atmospheric engineering that led to great extinction events and
killed probably more organisms than any mediator ever has. Yes,

(29:41):
but anyway, so plants get most of their energy from
this harmless process, why would they ever need to trap
and insect and digest it. That just seems like it's
it's redundant. It doesn't make any sense. And to find
the answer, we can look at where these carnivorous plants
usually live. So most often you're going to find them
in inhospitable growing conditions, the nutrient poor soil of bogs,

(30:06):
fins and swamps, places where there might be plenty of
access to sunlight, hopefully water too. But in the words
of the old man from pet cemetery, the ground is sour.
There is not enough nutrition in the ground, And so
what does nutrition mean for a plant? This is the
first fact. By the way, carnivorous plants eat for nutrients,

(30:27):
not for energy. They don't need the chemical energy within you.
They need your compounds or your molecules. So, just like
human beings, plants rely on the environment for essential nutrients. Right. So,
if if you're stuck in an environment where you get
plenty of food energy through sugar, but you have no
dietary access to some essential nutrient like vitamin C, your

(30:49):
health will deteriorate. You've probably read about this on on
old like ships, you know, the sailors out on the
war or whatever. Exactly. So, without vitamin C, you're gonna
start to experience some not so great symptoms. You're gonna
have dry splitting hair, rough scaly skin, inflamed gums and
gum bleeding, nose bleeds, wounds, and bruises that won't heal.

(31:13):
This is all because your body can't synthesize vitamin C
on its own. You have to get it from your diet,
and eventually, if your diet is really deficient in vitamin C,
you're gonna develop scurvy, in which you experience extreme fatigue,
loss of strength in the connective tissues all over your body,
Like your body needs vitamin C in order to make
collagen these for these connecting tissues and uh, and you're

(31:36):
also gonna have fragility in the walls of your blood vessels,
which is as not good as it sounds. Likewise, plants
need essential nutrients to write that. They can't make everything
they need to survive within their bodies. They have to
get it from their environment. And one example of this
is nitrogen. So most plants get nitrogen through their roots

(31:56):
from the soil around them. They reach out into the
ground with all of their root and they pull up
these molecules. They pull up these nitrogen atoms from the ground.
And if the soil is nitrogen poor or gets robbed
of nitrogen somehow, like apparently this can happen if there's
over introduction of carbon into the soil, plants in the
area can suffer nitrogen deficiency, which is kind of a

(32:18):
scurvy for plants. You see with the stunted growth, leaves
turning yellow and pale, and body structures that look kind
of wilted or sick. So, if you are the plant
equivalent of a vitamin C starved sailor with bleeding gums
and fragile joints living in this nutrient poor soil. Where
do you get your essential nutrients? Well, you could snatch

(32:39):
up and digest something that has plenty of nutritious molecules
in it, like an insect, you know. And and we
discussed in a previous episode, the Weird Mushroom episode that
you see this exact scenario play out with with oyster
mushrooms in which there's a nitrogen deficiency and therefore they
have adapted to prey on nematodes and in some cases spiders. Wow,

(33:04):
I didn't know that. Yeah, it's pretty crazy. And then
of course we turn around and eat the oyster mushrimps. Well,
they are delicious tasting. You never eat a spider on purpose,
but who knows how many times you you get one
down the chain. That's the old myth, right, the average
person eats sixty spiders a night. I think it's crawled
right in there. That's a myth, right, that's not true,

(33:24):
that's an Yeah, that's an exaggeration of the myth on
my part. Alright, so we have okay, so here's another
fact about carnivorous plants. Uh So the this trick, this
insect eating trick in order to get nitrogen and other
nutrients that the plant needs. It's a good trick. And
for that reason, the carnivorous phenotype evolved multiple times independently,

(33:47):
So there was no one carnivorous ancestor plant that all
carnivorous plants today can be traced back to. This is
an example, or scientists think this is an example of
what's known as convergent evolution. So it would be kind
of like flight. There's no one flying animal that all
flying animals today evolved from. Flight is a solution that

(34:08):
was reached by evolution in different branches of the tree
of life, independently and at different times. Uh coast three
different times. Yeah, Carnivory in in plants is the same way.
It's a survival strategy that's so good. Different branches on
the tree of life adopted separately in separate evolutionary contexts. Uh.

(34:28):
Let's let's go to a third fact related to the
previous one. Carnivorous plants come in a lot of different varieties.
You're probably familiar with venus fly traps, but the superstars, Yeah,
but they're not the only ones. There are multiple different
types of carnivorous plants. It actually occurs in According to
one source, I found at least nine families, nineteen genera,
and six hundred species of plant, and so it could

(34:50):
be more by now. Yeah, I think just a few
years ago it was that I saw a source saying
five hundreds. So apparently just continually or discovering new examples. Yeah,
So what are the different types of carnivorous plants. Well,
you have a few different models, a few different methods
out there. First of all, snap trap plants, venus fly traps,
water wheel plants. This is the the iconic example of

(35:14):
the little trap that slowly opens and then a fly
lights in the middle and the gates close over it.
So it's it's kind of a trigger plate kind of. Yeah,
it's exactly has a trigger plate. It works very much
like a like like I said, like a like a
wolf trap or a fox trap or a bear trap. Right,
and uh, and these are you know, these are famous
because they're beautiful, they're they're relatively easy to cultivate or

(35:36):
at least by the store and keep alive for a
certain period of time in your home. I had one
when I was a kid one time and I think
consolation for the fact that my mom took me to
a very long, boring time at a plant nursery where
she was buying some flowers or something. I asked and
returned to get this venus fly trap, and I got
it and it was very cool. But I recall I

(35:58):
got at home and I couldn't get it to close
on any thing. Oh yeah, I remember being I never
had one as a kid, though certainly it would be
the only plant I would have been interested in as
a child. I had. I had one for a while,
maybe ten years ago. My wife and I had one
called Monster Tom, and we kept hoping it would catch flies.
I would be one of those things where you would
let a fly live in the house because you're like,

(36:19):
all right, let Monster Time take care of it. I
don't think the Monster Time ever ate a single fly,
but it was still a beautiful little plant app around.
I wonder if the domesticated venus fly traps have gotten soft,
you know, maybe they just don't pray on flies, like
they just know they've got to have like big beautiful eyelashes, right,
I mean, because but of course, these these are known
as the snap trap plants, and they're not the only

(36:39):
kind of This also includes water wheel plants, right do
we say that? Yes, Okay, I'm sorry, but there are
plenty of other kinds too well, like how about pitfall traps. Oh. Yeah,
the main example of this being picture plants. Yeah, which
is which is one? I believe they have them in Newfoundland, Canada,
and that's where I kind of encountered them early on

(36:59):
one really good yeah, or at least some variety of them,
because they're pretty widespread and these are lovely specimens. The
leaves fold into deep, slippery pools field with digestive ensigns,
So it's essentially a champagne flute that's filled with insect death. Yeah,
but with it's got the slippery slide going down into it. Yeah,
so the the insect light slides down scot and the

(37:22):
goo and dissolves. So it's it's it's kind of monstrous,
but also be their beautiful plants. So you seem a
lot of botanical gardens. I'm always seeing them, often with
some kind of chemical attractant to to bring the insects in,
to lure them down. Uh. And then there there's something
I've read about the special surfaces, right, like the surfaces
on the lip of the picture plant becomes slippery when wet,

(37:44):
so it's hard to scramble back up them and just
kind of slide, uh intellectably down into the pit. Yeah,
and of course it's worth worth reminding everyone. Like one
of the key things here is that is that plants
and insects and have a hat if a long history
with insects serving as pollinators for for so for so
many different plant varieties. Oh yeah, there's actually a study

(38:07):
about that I want to mention in a few minutes here.
But anyway, the picture plants, Yeah, that's so they're they're
they're numerous varieties of this. And the earliest fossil evidence
of a carnivorous plant might be a picture plant, uh,
the mid early Cretaceous uh Archaeomorpha long as servia, was

(38:28):
discovered in what's now northeastern China, and researchers are now
split on the matter, with newer research arguing than it
might not be a picture plan at all, some of
the others, especially the earlier papers, saying that, oh this,
this definitely is a picture plan or at least sort
of a proto picture plant, and so it's it's kind
of a problematic fossil right now. But there's a possibility

(38:50):
other than that that there's not a whole lot of
fossil evidence of carnivorous plants. So any dreams you might
have out there listeners for a for like a prehistoric
giantly like a giant one that's eating dinosaurs or prehistarring mammals, Uh, well,
it's not in the fossil record at any rate. Man,
that's a bummer. Three. History gives us giant toads, giant scorpions,

(39:12):
but no giant carniverous plants. Of course, there are other
varieties of carnivorous plants as well. There are lobster trap plants. Oh,
these are great. There They go by the pickle jar principle, right, Yeah,
you reach in, you grab the pickles, and you can't
get your hand back out right or indeed, as the
name applies, lobster traps various crab traps. Does anyone has
ever used these? Know that the creature crawls in, but

(39:35):
then it can't quit get out again. And that's exactly
how these plants that do that with through special structures
that end up trapping the creature. Yeah, I think there's
a certain element of this and I think it's actually
a type of picture plant, but it had there's an
element of easier to get in and apparently easy to
get out until you're inside. In uh In the cobra lily,

(39:59):
this cool example of an American carnivorous plant that I found.
It grows in I think northern California and southern Oregon.
Uh And it's this beautiful looking plant that has a
has a picture and is in some way carnivorous. But
it's got an opening on the bottom and then the top.
It's kind of translucent so the light can come through,
so I assume to an insect, it looks kind of

(40:19):
like you can exit through the top until you get inside,
all right. Up next, we have sticky traps a k a.
Flied paper traps, and examples here include sun dues and butterwartz.
So the leaves exude a sticky substance that catches lighting insects.
Pretty pretty basic, but hey, it's a winning design. I mean,

(40:40):
I've I've got the willies from glue traps because I
know the stories of people who have tried to use
glue traps to catch rodents in their house. And that's
just a sad scene. Yeah. The tragedy of glue traps
is that they sound humane on the surface of things
not but they're they're not at all, especially when you
when you realize that reptiles that gets caught in them,

(41:00):
they're going to suffer a long time because they've evolved
to to to go a long time between meals. Uh so, hey,
if you do. I have had to remove a snake
from a glue trap before, and if you use oil,
that will really help. I think I think we used
olive oil and we're able to free a specimen. Yeah,
that's amazing. Well, well, I don't know, it's amazing. I

(41:21):
didn't know you were such a hero, Robert. Well, it was.
I feel like, can you come get my cat out
of the tree? Can you come get my snake out
of a glue trap? Well? I have you. I have
found that if I am if I encounter an animal
with my son, I'm often even more humane, Like not
not so much snakes, because I generally am going to
be cool with snakes. But this most recent trip, we
came across some blackwood of spiders and like, actually three,

(41:45):
you're like really close to um to a house, and uh,
you know, normally once the instinct that I grew up
with is if you find a blackwoodo of spider, you
go ahead and kill it because it's you know, it's
a highly it's it's not a good animal have around.
You don't want that thing by me, right, I feel
like we should learn to resist that impulse. I think
so too. I like, you know, if it's not hurting us,

(42:07):
then we shouldn't crush it. So we just checked it out.
We actually caught one and put it in a little
glass and looked at it for a little bit and
then released it further away from the house. But then,
of course there is one other major type of of
of carniversus plant, right, these suction traps. Yes, these involve
highly modified leaves in the shape of a bladder with
a hinge door lined with trigger hairs. H So these

(42:30):
are the ones, if I'm picturing them correctly. Um, these
are the ones that kind of remind one of of
pipe organs with a little bit on the top, like
a little lid on the top of the organ pipe. Yeah, okay,
I don't think I've ever seen that, or maybe it's
more like no, no, it's more like the I'm I'm
comparing it to cartoons. I think in my mind we

(42:51):
have like a steam engine or something, and they have
the little top that flips up on the top of
the the sauce pipe. Yeah, kind of similar to that. Okay,
uh so, hey, let's hit the next fact about carnivorous plants.
Among the killer plants, you've got a couple of different
major varieties, right, So you've got carnivores and then you've
got the proto carnivores proto carnivorous plants. So what what

(43:14):
would we mean by that? A proto carnivorous plant is
a plant that has the tendency to catch and kill prey,
but doesn't yet have the capacity to directly digest the meal. So,
for example, there are some picture plants that do not
produce their own digestive enzymes, but rely on bacteria to
dissolve organic matter in the traps. And some botanists would

(43:36):
class proto carnivorous plants as taxons that are part of
the way. They're right there on the evolutionary path to
becoming carnivores. Yeah, it's interesting when we consider that that
many carnivore lineages, you know, they enter into the carnivore
game via proto carnivore lifestyle. Yeah, so yeah, it's it's

(43:57):
it's it's kind of like seeing evolution in action, and
I can't help it. To consider the relationship between figs
and fig wasps, that's interesting, which I think is a
great example of, you know, a complex relationship, really a
mutualistic relationship between a plant and a particular insects species.
I've never heard this mentioned as an example of of

(44:19):
a carnivorous plant, but Robert tell us how it goes down.
What's the relationship? All right? Well, uh, again, it's a
mutualistic relationship. But there there's some there's some nutrients absorbed
to at the end of the story. So the basic
scenario here is that fig trees need wasps to transport
pollen from one plant to the other. The plant provides
a fig wasp with their only source of food and

(44:41):
shelter um. What we call a fig is actually a
structure called a seconium, and it's really more of an
inverted flower than a fruit, with all its reproductive parts
located inside. And after a female fig wasp flies over
from her home fig plant, she has to travel to
the center of seconium to lay her eggs, and to

(45:02):
get there, she climbs down a narrow passage called the
osteo passage is so cramped that she scrapes off her
wings and her antenna during the descent. It's just a real,
real nightmare scenario. And then once inside, there's no getting
back out and flying to another plant. Uh, it's like
like finding a narrow hole in a cemetery and climbing
down into a grave, just ripping a bunch of skin
off in the process. And then when she's down there, well,

(45:25):
she better hope she's in the right place because fig
plants boast two kinds of figs, male caprifigs and then
female edible figs. If she if she winds up an
inedible with fig she eventually dies from exhaustion or starvation.
She can't lay her eggs there, the stylus is in
the way, but she at least delivers the pollens, which
is kind of a cool, a cruel trick, right. Um,

(45:46):
we see the mutualistic aspect here, but it also kind
of breaking down right Like the right plant, the plant
gets what it wants, but the wasp doesn't get what
it wants. Now she enters the male caprifig, she'll find
male flower parts perfectly shaped to hold the eggs. She'll
eventually lay. The eggs grow into larva, which then developed
into male and female wasps, which emerge after hatching. The blind, wingless,

(46:10):
wingless male wasp will spend the remainder of their lives
digging tunnels through the fig. The female wasps then emerge
through these tunnels and fly off to find a new fig,
carrying pollen with them. Now, and that is a crazy process, Yeah,
it is. It's it's it's wondrous, wondrous. I had figs
in my backyard this this year, and uh I thought

(46:31):
about it every time I went out there to check
on them. Well, wait, then, is it accurate to say that,
in some sense the fig tree is consuming the wasp
that is stuck inside it. Yes, because this is what
happens in the death fig um. When a female wasp
dies inside an edible fig, and enzyme in the fig
called icing breaks down her carcass into protein. So the

(46:55):
fig basically digests the dead insect, making it a part
of the resulting ripened fruit. The crunchy the crunchy bits,
and the figs, though or seeds, not anatomical parts of
the wasp in case, and he was wondering. Now, One
thing I do think about here is that a fig
tree doesn't seem to me to be something that is
suffering from a lack of nitrogen or some other nutrient

(47:18):
or or is it. I mean that that's not my
understanding that it's necessarily suffering, but it just gets some
kind of maybe even if it could survive without these wasps,
I'm not saying I know that it could, but even
if it could, it just gets a little extra boost.
I guess it's like using every part of the buffalo, right,
I mean, the wasp is in there, it's it's not

(47:39):
going anywhere. Why not digested? Why not digested? I mean
to sort of anthromorp anthropomorphize the evolutionary process here of bit.
But it's it's an interesting example. I think of certainly
a complex relationship, a mutualistic relationship where it's kind of
like thinking of it as a corporation. Right, So you
have you have Big Treek Corp. You know, and they

(48:03):
have all these different departments, and most of the departments
are related to fruit production and UH and and wasp
relations but there is definitely a wasp dissolving and digesting department.
It's not the primary department. It's on the basement. Yeah,
it's in the basement, but it's still plays a role
in the overall company structure. Okay, okay uh. And it's

(48:25):
you always got to put the payroll in. Yeah. Now,
I wanted to see if there was any interesting new
research from this year on on carnivorous plants, and I
can't across one paper I thought was kind of interesting.
It's called Pollinator prey conflicts and carnivorous Plants when flower
and trap properties mean life or death from scientific reports

(48:48):
published this year in and it was studying plants of
the genus Drosera, which are the sun dues. Right, we
talked about those the sticky trap plants, and its studied
how the play an't solve a particular problem if you've
thought about this. If you're a carnivorous plant that wants
to draw insects into a death trap, but you're also

(49:09):
a flowering plant that wants insects to spread your pollen
for reproduction, how do you make sure that you don't
trap and kill the insects that you need to pollinate
your flowers. Um, I'm about to say a metaphor for
this that might be the worst metaphor I've ever tried
on this show, So so stop me if I'm going
off the rails. It's kind of like if if you

(49:32):
couldn't have sex without the help of a certain species
of live wild rat, but you also have rat traps
all over your house, like kill traps. This would seem
to lower your reproductive fitness. So instead, what the drosera
plants do and study is they offer different visual, spatial,

(49:53):
and chemical signals that selectively attract nonpollinators to the traps,
so that they've adapted to have selective appeals in the
traps versus in the pollinating structures. What's kind of like
imagining these, um, these hotels and horror movies where they
cannibalize the guests, like you gotta keep your YELP rating
up enough you get more guests, Exactly, You've got to

(50:15):
have enough real guests. But then at the same time,
you need guests to eat, so you've got to find
that balance. Yeah, So in in my horrible analogy, it
would be sort of like having traps that are designed
to to kill all the rats, except your sex rat
that you need for reproduction. So yeah, let's let's discuss
the real carnivorous plants, the plants that really do prey

(50:37):
on vertebrates. Okay, well, we've got to start by discussing
the alleged ones that prey on vertebrates. So the one
I want to start with is the Pulla chill Insis. So,
this is a bromiliad plant that grows in the arid
parts of the Andes in South America. It's known as
Pulla chill insists. And it's sort of because it's a bromiliad,
it's going to be a cousin of like the pineapple,

(50:59):
and it kind of looks like a pineapple. It looks
like a giant, woody pineapple with yellow green spikes extending
out at an inclined angle from the trunk. And it
has been widely reported on popular websites and a few
news sources that this plant is known as the quote
sheep eating plant because it sometimes feeds on the carcasses

(51:20):
of livestock caught in its spines. For example, there's ABC
news piece about how the Royal Horticultural Society and Great
Britain managed to grow one of these plants in a
greenhouse in Surrey, and the story was about how the
plant was about to flower. I think it takes a
long time to do that, But the article claims quote
in the andies it uses its sharp spines to snare

(51:44):
and trap sheep and other animals, which slowly starved to death.
The animals then decay at the base of the plant,
acting as a fertilizer. The RHS feeds its specimen on
liquid fertilizer, and then the quote a horticulture is saying
that obviously would be problematic who feed this plant quote
its natural diet um. So, despite these reports, most of

(52:06):
which sort of repeat the same thin summary claims over another,
over and over, I have been unable to find any
evidence in the scientific literature that these plants are really
known to do this to trap and kill large animals
like sheep, And honestly, looking at a bunch of pictures
of them, I'm also having a hard time seeing how
this would happen, like they look like they would be

(52:29):
painful to fall into, but not deadly traps. Also, I've
read a few accounts of people who claim to work
around the puya and don't report anything about this. So
this makes it seem to me like this phenomenon of
sheep becoming trapped in puya growth, dying, and then fertilizing
the base of the plant is something that maybe conceivably

(52:50):
could happen by coincidence. Like I guess you could accept
that rotting animal flesh is generally a decent fertilizer, but
it probably doesn't happen off and enough to qualify as
a real evolutionary adaptation by the plant. Yeah. And plus,
I mean, there are plenty of animals that are already
going to play prey on a sheep, And then if
you're having sheep that are raised and based on an

(53:13):
artificial population of sheep, they're gonna be there's gonna be
a higher susceptibility to strange it unnatural deaths. Right. Yeah,
So I'm skeptical of this one. I think unless somebody
can send us some really good evidence that this actually
takes place, I'm going to say this one actually looks
like a myth to me that has somehow made it
into news reports. I think that is a safe bet.

(53:33):
But then there's another one that is definitely not a myth.
Though we have to be a little careful and how
we characterize it. So I want to talk about nepenthees,
the tropical picture plants. So these are pitfall traps, right,
Like we've talked about picture plants where they've got a uh,
they've got a deep well that has some killer fluids
in it, and they want you to fall in and

(53:55):
get stuck and die and dissolve. Now it's it's definitely
worth saying that the natural prey of these plants are invertebrates.
They're going to be insects. But some of these traps
can grow like more than forty centimeters deep or hold
up to two liters of digestive fluid. That's huge. That's

(54:15):
like a you know, that's like a big soda bottle.
Like with some of its various species having traps this big,
it's sort of natural to wonder if anything bigger than
an insect ever gets digested, And I'd say the answer
appears to be both no and yes. So, like I said,
first of all, invertebrates are clearly the main prey of

(54:37):
these plants. Um they they appear insectivorous by evolutionary design,
But animals come into the picture as well. One one
sense is more mutualistic. Like, there are several picture plants
that seem to have this non predatory symbiotic relationship with
vertebrates like birds, bats, and shrews. And it works like this.
You've got a picture and it's got sweet eat nectar

(55:00):
all along the outer surface, and a bird or a
forest rodent comes along besides, I want some of that nectar,
And while it's hanging out of the opening of the
picture plant, it just happens to deposit some feces inside. Now,
normally you would not expect an organism to have an
adaptation that incentivizes animals to poop inside it. But guess

(55:21):
what those feces are rich in nitrogen? Yeah, exactly the
nutrients that the plant would normally need to get by
killing insects. So there are types of picture plants that
also seem to provide like a roosting shelter for bats
as well, and the bats to do the same thing.
They poop into the plant and the plant gets some
sweet nitrogen out of it. But with some of the

(55:45):
larger tropical pictures, what if a small mammal or two
fall all the way in, would it be able to
get out? And if not, would the plant eat it?
I think the answer is dinging ding. You bet. This
is this nightmare scenario I encounter anytime I use a
composting toilet. Oh. No, those things smell bad enough anyway. Yeah,

(56:07):
even when they do. I was in a really good
one last week. Oh I shouldn't bad mouth, and I'm sorry.
I've been near one that smelled really bad. But it's
still horrifying because especially like in my case, I'm putting
my son on it, and I was like, oh, he
could just fall right down there, and then I guess
I'd have to go down there too, like the fluke man. Right, Yeah,
oh man, this is a horrifying scenario falling into a

(56:28):
picture trap. God. So here's the evidence. There is a
photo and video documentation online of a nepenthes research expedition
that took place first in October, and they were going
to Mount Victoria in the Philippines and they were studying
specimens of nepenthees at in Burrow I wouldn't named after

(56:50):
our our favorite at in Burgos endemic to the region
and with the species not and not Attenburgh. But they
found one picture of this plant that contained a wild
caught dead tree shrew, and they showed it in photos
and on video, and a return expedition two months later
showed the skeletal remains of the shrew covered in a

(57:12):
sort of layer of first So essentially all the soft
tissues of the tree shrew appeared to have been digested
by the plant. So does the picture plant naturally target
vertebrate mammals as prey. Probably not, but if there's one
on offer, yeah, I don't mind if I do. That
seems to be the approach. But now the real question

(57:33):
is could it be possible for a real world plant
to be the man eating tree, that the killer tree
that would trap and kill large megafauna like a deer
or a bear or a human being mm or even
something like a raccoon? Right? I mean, oh yeah, it's
settling for a raccoon medium size because because the even

(57:54):
the the bat possibility and the shrew possibility is kind
of iffy, right, So anything larger than it becomes increasingly fantastic. Yeah.
So I will say, first of all, I found no
evidence that a plant like this already exists. We'll start
with the bad news, but the good news or maybe
the bad news, who knows what's good and bad. It
depends where you stand on plants killing and eating humans.

(58:15):
Is that there's some interesting leads. So first of all,
I want to consider the possibility of a proto carnivorous
bramble trap. So I watched a video blog and this
is not scientific information. This was a video blog by
an Irish sheep farmer, and this guy was personally insisting
that the BlackBerry brambles on his land are carnivorous, or

(58:37):
he called them carnivorous. I think more accurately you would
call them proto carnivorous. But if he's correct, But here's
his argument. He says by demonstrating how his sheep become
trapped in these brambles all the time, they get like
they get their wooly coats caught in the hook like thorns,
and then they struggle and they get more and more
tangled in the branches as they struggle to a escape.

(59:01):
That's kind of interesting. I guess the idea is that
they get caught, they can't escape, they die. It's kind
of like what was being alleged with the Puya chilensis,
that they would fall down near the base of the plant,
rot and fertilize the soil. Well, even if they in
doing this, if they didn't kill the animal outright, if
they even if they didn't allow starvation to occur, they

(59:22):
could conceivably you could conceivably have the plant just holding
it long enough for a predator to come take advantage
of it, eat part of it, and then but still
leave portions of the creature to rot. Oh, that's interesting too,
I hadn't thought about that now. I do want to
say I'm not going to endorse the hypothesis of carnivorous
brambles here because I think we don't have evidence that

(59:44):
that's necessarily what's going on. I think you'd have to
demonstrate that this is actually an adaptation towards which bramble
evolution was shaped like where they're similar wooly animals native
to the regions wherever these plants evolved. Would one of
these animals rotting at the base of the bramble plant
really provide enough nutrition incentive to make a major difference

(01:00:06):
in survival and reproduction like a would the would the
nutrients it provides matter enough for this to be an
evolved trade that is targeted by selection. Yeah, Because to
come back to the fig tree, scenario. Think of it
as a well run corporation. At what point does do
the do the masters that do the do the CEOs

(01:00:27):
of the border directors or whatever we're going to invest
in the processing division. Yeah, it's like, tell me more
about this, uh, this, this, this sheep eating division that
you're working on this project. All right, let's hire some
more people, let's let's invest more in that, and let's
bump it up in the overall hierarchy exactly. So. I
haven't seen evidence that that's what's going on with the brambles. Yeah,
but given all these questions, I do want to say

(01:00:48):
I could believe it's possible that some bramble type plant
could establish an evolutionary pathway toward proto carnivary and eventually
full carnivalary, starting with accidental snagging. This accidental snagging of
sheep and other unfortunate creatures that are covered in suicide
vel crow. You know, this reminds me of a specimen

(01:01:08):
that I encountered in Arizona last week, and that's the
death's claw or heartbrogaph item, also known as a grapple
plant or a wood spider wood spider that is gold.
They're pretty gnarly looking. Um. They they're from the sesame family.
But they're a hooked fruit. So it starts when it's growing.
Initially it kind of looks like a weird green banana.

(01:01:29):
And apparently it can be consumed. Uh we did. I
did not eat one, but I was told that, yes,
some people have things they can do with these. Um.
But it starts off like a banana and then it
kind of splits in the middle, and so it ends
up like you imagine you're like your hand making the
devil horns and then imagine if you had super long,
curvy fingernails on both of the protruding fingers. Yeah. And

(01:01:54):
so what it does is when a a mule deer
or a prong horn a horse or even a human
comes along, Uh, it latches onto the ankle. These these
these the devil horns here latch around and it becomes
and it carries the the fruit across you know, long distances. Um,
and it doesn't does not hurt the animal in question.

(01:02:17):
And actually they seem to have anti inflammatory properties that
are utilized in some folk medicines. But if this is possible, yeah,
why not a grappling mammal killing root as well, yeah, again,
I guess we'd have to come back to the question
of is the incentive there is the evolutionary incentive big
enough to work on these powerful structures. Yes, another way

(01:02:38):
to ask this question. Another scenario for this. How about
a human sized snap trap, sort of like what I
pictured in the grove of the killer tree at the beginning.
So imagine this. It's a venus fly trap, large enough
to capture and digest a deer or a bear or
a human like, not not so much necessarily like a
little shop Ahara's audrey too, but just a giant venus

(01:03:01):
fly trap. Just a trap doesn't mean a thing. Yeah,
it doesn't sing or leap out, but just large enough
to lay a trap that could snag a larger creature. Yeah.
So uh. There are obviously plants that move quickly. The
venus fly trap is one example of them. There's you know,
plants usually exhibit very slow motion motion that's expressed through

(01:03:21):
growth patterns rather than through fast moving of plant tissues.
But there are plants that fast moving tissues. You touch
a fern and sometimes the leaves can close. The venus
fly trap can snap closed. I'm not sure how big
and how sturdy, you can scale up those fast movements
and plants like I've never seen a plant with huge,

(01:03:42):
strong structures that exhibit fast movement. All the all the
ones I know of with fast moving body parts tend
to be pretty small. Yeah. Yeah, anytime you you see
the same thing when you're talking about giant gorillas. Right,
anytime you scale up morphology, you're gonna run into various
engineering limits and you end up having to change the
design in order to make it conceivably work. And then

(01:04:06):
in some cases, is it even possible to upscale that design? Yeah,
but let's just imagine. Let's say, okay, imagine you can
scale up fast moving plant body parts. Uh. Still a
couple of problems here. It doesn't take a lot of
compression strength to hold in a fly or a spider,
but imagine how many pounds of compression force it would

(01:04:26):
take to hold in a human or a bear that's
fighting to get out of a trap. This would have
to be a really strong, big, powerful plant. And I
guess my question is why would a plant evolves such
an extravagant morphological contrivance And does it even make sense
to imagine how it gets to there? Because remember carnivorous

(01:04:46):
plants tend to practice animal predation in order to offset
nutrient deficiencies in the soil. Right, that's the whole reason.
We go back to their growing in inhospitable conditions. They
can't get the nitrogen or some of their nutrients they need,
so they need to pray on animals to get those little,
those little molecules. But what would an organism grown in
such poor soil be able to attain human trapping size?

(01:05:09):
To begin with? Like, how does it get that big
and that powerful if it hasn't been trapping humans? The
whole way would have to It would have to sort
of like be scaling up as it goes, catching bigger
and bigger animals as it gets bigger. Ye, And why
would you why would it? Why would it evolve to
depend on increasingly larger and increasingly um, you know, more

(01:05:30):
rare uh specimens? Why why would it would be making
it's it's there would be there would be a tipping
point where it would just be making its work harder
for itself, and and therefore there would be less uh less,
it would be less advantageous to its evolutionary set. Yeah.
And another thing to remember as we've said on the
show before. In evolution, we've always got to keep in

(01:05:51):
mind bigger is not necessarily better. It seems better to
us because we like bigger trucks, but bigger bodies are
not necessarily better. Or as ms will not tend to
grow larger unless there's a clear survival advantage or reproduction advantage. Right,
it comes down to what the environment will bear, what's competitive.
I just just a few seconds ago, I I said
evolutionary ascent, which we often use in talking about humans.

(01:06:14):
But that's kind of a misnomer because evolution, in the
same way that there's no evolution, is not an upward
or downward movement. It is just a movement um. And yeah,
if you start thinking about it in terms of there
being a goal other than survival, other than propagation, than
you muddy the waters. So yeah, the the human size

(01:06:35):
snap trap, I'm going to say that that's something that
maybe could be engineered. You know, I could imagine in
the future, if you're you're tinkering with plant genomes trying
to create something weird, it's possible that that that's sort
of a a physical uh, something that's physically attainable and
plant morphology. I don't know, it might not even be that.
But even assuming it is that, it doesn't seem like

(01:06:56):
something that would arise in nature, right. It would need
to be a mad science who decided, you know, he
or she wanted a large man eating plant. Maybe you know,
an evil dictator who wanted it to live it at
the bottom of a trap door or continue feeding witches too. Yeah,
or how about this, how about a bio toilet for
for spaceship gardens. So going back to the picture plant idea,

(01:07:20):
encouraging animals to poop in it, like a compos bio
biological compost, biologically engineered compost toilet. Or maybe it's engineered
by a British nanny who is a druid who has
had her tree killed with a chainsaw that she used
to worship for years. She needs a new god and
so she genetically she studies genetics, she you know, masters

(01:07:42):
the art of crisper gene editing, and then she makes
this thing or has she just merely entered into contract
with the space toilets who overthrew another alien species because
they were tired of just being pooped into. Okay, Robert,
I think we're done. Yeah, we've got off the deep
end here, but I think we've covered some We've covered
some fictional ground here, We've covered covered some mythological, some

(01:08:04):
cryptid ground, as well as the the the the more
solid soil of of actual scientific inquiry, and nothing aid
us in the process. So I guess we're doing okay.
It would be a good way to go, though. It
would be a noteworthy way to go, not a pleasant
way to go. But yeah, it'd be good to be remembered. Yeah. Yeah,

(01:08:25):
because none of these scenarios, I think we can agree,
none of the scenarios of carnivorous plants actually sounds pleasant.
All of it takes place, that death ends up occurring
at the slow rate that is, uh, that is typical
of of the plant's slower approach to life. You'd really
be hoping a bear would come along and get into you. Yeah,

(01:08:47):
all right, So there you have it, carnivorous plants. Um. Hey,
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(01:09:10):
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(01:09:30):
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(01:10:01):
playin the foot part part