OK, And so without further ado, I am very excited and honored to
introduce you all today to a colleague and a dear friend of mine,
Doctor Jess Stevens.
Doctor Stevens is an assistant professor in the Department of Biology and the Co
coordinator of the Biology Education Program at Westfield State University.
She completed her BS in Biology at Butler University,
a Master of Science in Biology at Auburn University,
and her PhD in Plant Biology from the University of Georgia.
After completing her doctoral degree, she worked as a post doctoral researcher
at the University of Pittsburgh and then as a conservation scientist at the
Atlanta Botanical Center, Atlanta Botanical Gardens before starting
her faculty career, which is where we first interacted with
one another years ago in Rhode Island.
Dr.
Stevens research focuses on the evolutionary ecology of plant
interactions, especially in carnivorous plants.
She has published widely in peer reviewed journals and currently mentors
undergraduate students conducting research on projects that include the
influence of urbanization on plant communities.
In addition to her biology research, Doctor Stevens is a dedicated educator
who has published peer reviewed journal articles on effective college teaching
and works on grant funded projects to advance STEM education.
Please join me in welcoming Dr.
Stevens as she delivers her talk entitled Revisiting Darwin's Insectivorous Plants,
Modern Insights into Carnivorous Plant Evolution.
Thank you.
Can you hear me?
Let's see, which one is it?
This one?
Can you hear me?
It was working.
It's not.
Is it loud enough here?
I'll just use the microphone, I guess.
OK, hold on.
All right.
Can you hear me?
I'll try to project my voice as loud as I can.
So thank you all for coming today.
And thank you for the invite.
I'm really excited to be here at Salem State and talk about one of my favorite
things, which is carnivorous plants.
So usually when I give this talk, I focus more on my research.
But today I'm going to go more broadly into Darwin because it's his birthday and
I kind of just want to poll you guys.
What do you think of usually when you hear the name Charles Darwin just yell
out anything?
What's the first thing that you think of that people hear?
You know, when they think of of Charles Darwin,
what is the first thing they think of?
Evolution.
Evolution, what else?
Galapagos, barnacles, What else?
What was that?
Beaks.
Beaks, yes.
Are Darwin finches, Right.
So you might not know that Darwin was also an avid botanist,
so a lot of people think right away of his obsession with animals and so forth.
But he was a big botanist.
He actually was really fond of things like orchids.
He wrote a whole book on orchids.
But he was also really fond of carnivorous plants and at his time they
called them insectivorous plants.
So when he was on vacation in Sussex in England,
he actually walked across this species up here, Drosa Drosara rhondafolia,
which is a sundew.
And he was mesmerized by this plant.
He saw a mat of them in a little low lying area and they get their name Sundew
because they look like they have do on the leaves and they kind of sparkle and
glisten in the sun.
And at the time, many people wrote off the fact that they
always got insects stuck to them as something is just kind of, oh,
that happens.
There's not really any adaptation there.
But being Darwin, who he is, he was like, there's no way that this is not an
adaptive trait.
There's these plants were covered in 70% flies and he was like,
there's got to be something adaptive about this trait.
And so he actually wrote ASA Gray, who was one of the biggest and is one of
the biggest North American botanists that from North America.
And he was at Harvard at the time, and he wrote him lots of letters about
his obsession with these plants.
And in fact, this was a quote that he wrote in a
letter to ASA Grey.
So I care more about Gerothrae than the origin of all the species in the world.
And this is a big deal if you think about the fact that he's the person who wrote
the book on the origin of the species, right?
So he was very, very into carnivorous plants.
And I always like to tell my students, one of my favorite things about Darwin is
that he was a very good naturalist and a very good observer.
So I'm going to turn it on you for a second,
and I want you to pretend you're Darwin.
OK?
Here's a video of a Drosera capturing a family.
And this is a different species than the 1 he saw.
And I want you to take a moment and just ask yourself questions.
What do you wonder about this?
What kind of questions do you have about adaptation with this plant?
Go ahead.
And when you're thinking about it for a couple of seconds, talk to your neighbor.
What kind of questions or ideas come to your head?
None.
All right, great conversation.
So if anyone wants to share, please raise your hand.
What did you talk about?
What are the things that you wondered about when you look at this video?
Yeah.
OK.
So how did it know to move?
How did it?
What triggered a response?
So what is it responding to?
You think about movement.
What are things?
Yeah.
What environment or what caused it to evolve?
OK, So what environment did it?
Does it live in environment?
Why Prey.
Yeah.
What kind of mechanism in the plant controls that?
Movement.
So mechanism of movement, Yeah.
How does it digest its frame?
How does it digest?
So digestion all the way the way back.
Where are the sensors located on the plant?
Sensors.
So along with movement or digestion?
Movement.
OK, so sensory kind of thinking about the
sensory there.
Anything else?
Yeah.
How do they attract the insects?
Attraction.
Yeah.
Any others?
Mentioned, what type of food does this plant,
the species respond to?
Is it discriminatory on what it's actually eating?
And then how does the plant digest prey?
OK, so Darwin was really good at being
meticulous with data.
And So what he did is he took some of these plants back to his home in his
greenhouse and he set up these experiments.
And so to answer the first questions, 2 questions of like, why do they,
they trap insects and if they're discriminatory with their prey,
He tested a bunch of different substances on the plants on the sundews.
So he fed them hair, he fed them bone, meat, egg, nitrogen, phosphorus,
ammonium and salts, right.
The things that the plant actually responded to and digested I have listed
in red here.
So meat, egg, nitrogen and phosphorus are what the
plant actually digested the other substances.
And there's more than just this list.
They did not.
It did not respond to OK.
So this kind of matched up with Darwin's hypothesis.
He knew that these plants grow in nutrient poor Fens and bogs,
and thinking that they're nutrient poor habitats,
he expected there was selection pressure for these plants to evolve a way to get
nitrogen and phosphorus from something other than the soil.
So that's why he thought they evolved carnivore.
So this matched up with his hypothesis that there must have been some selection
pressure.
And they respond to things that have nitrogen and phosphorus, again,
because they're found in nutrient poor soils, right?
So then the next question is, OK, if that's a selective pressure,
how much of an adaptation is this?
Do they actually get nitrogen and phosphorus?
So then he set up a couple more experiments.
So he set up plants that were fed versus plants that were unfed.
Now, unfortunately, when he did the experiment,
all of the plants died and then he passed away after that.
So he didn't get to see it, but his son took the reins.
His son Francis took the the reins and set up the same experiment and he got
results.
His results were that the Fed plants grew larger, had more flowers, and had larger.
He was assuming they also had these things,
so he thought it was really related closely to the way animals digest food.
Because of this, he wanted to know like, OK,
so if they have acid to help breakdown the food,
maybe I can neutralize that acid and it would prevent them from eating the food.
So what he did is he had two sets of plants,
control plants that were just fed food with just regular food.
No, no.
A thing was added to it and then neutralized plants where he fed them food
with a basic substance on it so that when they, the neutralized plants,
were fed those items, it neutralized the acids that the plant
was producing.
So the plant couldn't digest.
So this showed that that there was some sort of acid that the plant is exuding
out to help digest prey.
So he blocked that and then they couldn't actually eat the plants or eat the prey.
So this is just three, these are just three questions he asked.
Like I said, he asked questions about movement and he
collaborated with somebody on movement with the Venus flytrap.
He was really interested in how that movement occurred.
But he took all those notes and he put it together in a book called Insectivorous
Plants that was published in 1875.
And I have up here Mary Treat, who is also a big botanist at the time in
New Jersey.
She was very big on carnivorous plants.
And she collaborated with him with that book,
gave him some feedback and a lot of information about carnivorous plants.
And if you've read, if you're a fan of Barbara Kingsolver,
the unsheltered book, she's actually one of the characters in
it.
That's where you might have heard that name as well.
So what do we know now since Darwin's time about these same questions?
Well, we know that carnivorous plants have
evolved in nutrient poor habitats.
And this is just a graph up here with see, I do that.
So substrate moisture is on this X axis here.
So dry all the way to wet on the Y axis we have nutrient poor to nutrient rich.
And if you take all of the carnivorous plants in the world,
you find that they are not in this category of the nutrient differences here
or dry habitat.
You find most carnivorous plants are found in wet habitats that are nutrient
poor.
So all the carnivorous plants in the world,
you find them in these habitats that have set up this this scenario for selection
to get prey so they can get nutrients from other than the soil.
And we also see when now that something that Darwin didn't have was isotopes.
So there's a lot of studies now that have looked at nitrogen isotopes to track how
the nitrogen moves from the animal into the plant.
And we find that plants that were fed hit most of their nitrogen is from the actual
insects and not from something else in the environment.
So there's definitely a big difference between how much nitrogen they're taking
up if they're eating prey.
OK.
And lastly, there's been numerous, numerous studies have have supported what
Darwin's son showed, that when you give these plants prey,
because they're getting more nitrogen, they're growing larger,
they have more seeds, they make more flowers.
So again, showing there's a fitness benefit to
eating prey.
What do we know about digestion now?
We know a lot, but we still have a lot to learn.
So we are just on the cusp of really understanding how digestion works in
these plants.
So I have up here a a figure from this paper that came out recently.
And up at the top you have carnivorous plant, in this case a Venus flytrap.
And you have a human on the other side showing like how the digestive systems
are set up differently between the plant and the human.
So in humans, we have three parts of our digestive
tract, right?
These carnivorous plants, all of their digestion,
their absorption has to happen with the leaf, the trap structure.
So that's what this top part is showing, is that all three of these systems,
these ways we digest, they're all happening within the leaf of
that carnivorous plant.
When we look at the 2, so this is the plant side,
this on the right side is the animal side.
We have similar things happening in our stomachs.
We secrete acid, hydrochloric acid to help breakdown food.
These plants are doing something similar.
There's question marks here because we don't know across all plants,
but they're also releasing hydrochloric acid.
And their acid levels are a little more basic than humans like ours are like at
the pH of 1 carnivorous plants, about two or three,
but they're still acidic.
On the outside of the plant, there's secretion of enzymes.
So Darwin again thought pepsin was involved with carnivorous plant digestion.
Sure enough, we have pepsin type enzymes that the
plants are secreting through exocytosis.
And humans we're, we're secreting our enzymes the same kind
of way.
Then the absorption piece, there are different things that are
absorbing the, the actual ammonium, the phosphate, the the, sorry, the,
the nitrogen.
So like there is absorption of those things happening similar to what we see
in our gut system.
And for larger macromolecule type things, there's endocytosis where the plant is
able to actually engulf some of these larger compounds and bring them in and
absorb that prey.
So very similar kind of functions.
What's also neat, in the last 10 years, we now know that our microbiome plays a
big role in our digestion, right?
We're seeing this in carnivorous plants as well.
So not only are they making acids, making enzymes to digest prey,
but there's a microbiome that's also contributing to the breakdown of prey
items.
So this here is a utricularia or bladder wart.
So this plant, the aquatic species have these little
bladders here and that's how they trap prey,
prey they have like pull in the prey item.
And the study was looking at is the microbiome in the aquatic habitat outside
of the the bladder different than the microbiome inside the bladder.
And sure enough, they did find differences.
So these are just two different sampling of the bacteria.
This is outside the bladder, this is inside.
So you have differences between the prey that they're just showing that there's
different or differences within trapped in the outside.
They're just showing there's different microbial communities.
So there does seem to be some selection by this plan of what their microbiome
looks like inside the bladder versus what's on the outside.
And this isn't the only study that has found this.
There have been numerous studies of carnivorous plants that have shown that
they have this whole bacteria microbiome with eukaryotes and also a fungi that
help digest prey.
And we're just kind of hitting the surface of that right now,
trying to understand that those relationships.
And this paper came out last year in Nature, so big journal.
And this was one of the coolest findings, I think.
So Aunt Roshira, our little sun do where the mucilage is
here they found that there is this acidophilic fungus that so acidic philic
means acid loving fungus that colonizes the mucilage.
So this is where the acid's produced on these plants.
And what they found is that it's at quite a high rate compared to the environment.
So here's Moss, here's other vascular plants.
So in Drosser on the sundews, you find this fungus quite regularly
colonizing that mucilage.
What they found after they did some inoculation treatments is that that
fungus actually helps digest prey.
So there's this relationship there between not only them being able to break
down the acid, but they're using a fungus to also help
breakdown food in this kind of commensal relationship, right?
So there's all this new research coming out about how these plants are using
these microbiomes to also help digest prey.
So to kind of summarize what Darwin was interested in,
what we now know is that yes, these plants evolved in nutrient poor
habitats and therefore there was strong selective pressure to evolve traits to
capture and digest prey.
So Darwin did these experiments supporting this,
since this time we have a better understanding of all carnivorous plants
that they do live in nutrient poor habitats.
That they are getting nitrogen and phosphorus from their prey items,
and it does give them a fitness benefit, right?
We've seen this time and time again in carnivorous plant research.
The other thing Darwin was really interested in is knowing whether or how
this plant digests prey.
And yes, they're similar to animal digestion.
It's not completely the same like he thought, but there's similar mechanisms.
Enzymes are similar.
The the Pepcid enzyme is slightly similar.
These plants also have chitinase, which help breakdown exoskeletons of
insects, which we don't have.
But there's similar ideas, Acid to help breakdown,
enzymes to help breakdown, and then they absorb similar to our
digestive tracts.
Yeah, but there's still so many more questions
as you guys, you know, have up here.
There's a lot of questions to still ask about these plants and Darwin would be
amazed now.
So we have at this point discovered roughly 800 plus species of carnivorous
plants.
And here are just a couple of pictures of those traps, these different plant types,
so all sorts of variation in how they're attracting, capturing and digesting prey.
And again, more than 800 species known worldwide.
Darwin only really knew about the Sun, Dews and the Venus fly trap.
So that's the only ones he played around with.
But now we know there's a lot of ways these plants can trap and digest.
Pray.
The other really interesting thing that would have blown his mind is this has
happened independently evolved 9 times, meaning that all carnivorous plants
aren't necessarily they're related.
We have independent evolution of this whole suite of traits to capture and
digest prey.
So it's been convergent evolution on these suites of traits to capture prey,
and they all kind of do it a different way, right?
So I'm going to go through just some of the different trapping structures to give
you a feel for kind of how they trap prey.
So Sundews eutricularia, which are the butter warts.
Butter warts basically look like they have butter on the leaves.
That's where they got their name.
Venus flytraps that they've niche partitioned their food sources.
So these tend to like really small fruit flies,
while Venus flytraps like larger flies, right?
So they've kind of diverged in what they eat.
And then we're going to talk about my favorite groups, the pitcher plants.
So these are called pitfall traps.
These are passive traps, and this group up here are Nepenthes.
So these are found in Southeast Asia.
And I have this picture up here.
So you can see the diversity of traps, right?
Lots of variation in traps.
Again, these are leaves, and they all look very different across
species.
Why might you think they look different across species?
Yeah, to catch different craniums, to catch different craniums,
that's my question.
That's exactly what I was trying to figure out, right.
So that is why I would.
None.
So to give you a little background of the plant structure before I go into how I
measured the leaf pieces.
So this is a trap and there's these 4 zones to it.
So there's an attraction zone, a conductive zone,
glandular zone and detentive zone.
And then we have the hood, the opening, which is the mouth, the orifice, the lip,
this wing here, and then the pedial at the base.
So up in the attractive zone, it gets its name because it's an
attractive.
Looking at and to be able to see it in 2 dimensions, it collapses it down.
So you see like where that point falls in this kind of two-dimensional axis.
So each dot here is a different individual, right?
The grey dots represent the shorter species,
the black dots represent the taller species.
And what these arrows tell you is that how these traits like these individuals,
what traits they have on that two-dimensional space.
So all of the black dots here have larger openings to their mouth and they're
taller and they have fewer of the hairs.
That's what this is showing here because it's on this side of the line,
on this side, these individuals have more of those
hairs.
They're.
They have to go into and they have to direct them towards the mouth.
So that's why we we are thinking that the wing probably is also more common in
small species.
So what this says is yes, there are correlation of traits across
the phylogenetic tree of Saracenia of of pitcher plants.
Small pitcher plant species tend to have more hairs on the outside.
They're smaller, They have a wider wing of a broader wing
and they have a bigger mouth opening.
And then the the tall ones are the opposite.
So similar to what we saw with the Seracinia minor.
So if we collapse these all these traits like I did before by species onto a
principal component analysis.
So again, in this case, each dot represents a species.
And here's all the species here.
These arrows tell you what these traits are correlating with.
So over here, these individuals are taller,
they have less hairs, individual or species on this side have
more hairs, and then these are going to be a species
that are much smaller.
So if we visualize this, the species that fall out here,
these four species are all about this big purple pitcher plant,
or they lay flat on the ground like this one.
See this wing here.
So they're really small.
They have lots of hair on the outside.
They usually have a bigger wing.
So they're down there at the bottom, clustered together.
These ones up here are kind of our mid level species.
So they're taller, they're standing upright,
but they're not very tall, right?
So they have the trichomes on the outside, they're mid level height,
that type of thing.
These ones over here are the plants that can get about this tall.
So they all group together.
They all are very tall and they all are missing the hairs on the outside of the
plant.
And that wing is virtually absent.
You don't even see it on these tall pitchers.
So again, these are leaves and you don't even see
that that wing on there anymore.
So do those traits we see that they're now correlated?
Do we see difference in prey from the tall species,
the mid level and the small species?
And so here's the phylogenetic tree, and here's our prey items represented as
just pictures here.
This is a heat map.
So anywhere there's like a bright red tells you that this species,
so this is the short pitcher plant species is eating primarily ants, right?
These are the short species up here, primarily ants,
a lot of these other species.
So the flying prey, so a wasp, other bugs like lacewings, flies, moths,
those type of thing.
We're seeing them in the taller species and down here in the taller mid level
species.
And in the fall this is even more striking.
So if you think about it, in the spring, most moths, butterflies,
they're in the larva stage, they're in the Caterpillar stage.
Now we've got more flying insects in the fall.
And this is where you see a huge majority of these flying prey are found in some of
the taller species out here in the shorter species.
Those ones who are in the corner still have a lot of ants.
So let's visualize this even easier because I know it's a lot of of stuff
going on.
So we're going to break them up into categories.
So I'm going to break up the flying prey into this category,
the crawling prey into this category.
And then we have kind of others which can do both.
So if we take our tree and these colors represent the leaf traits.
So anything in blue are our short picture plants with a lot of hairs on the outside.
Anything in like greenish blue are our mid level plants.
So this is one that's kind of this mid level.
Here's our Serasinia minor, the other mid level.
And then anything with red and yellow are going to be our tall pitcher plants,
right?
So we have color-coded our heights, these traits.
So let's take our three categories and compare them.
OK, So the circle size represents how much
they're eating of that different prey category.
And again, what you see when we visualize it,
short pitcher plants are eating short or crawling prey,
taller pitcher plants are eating more flying prey and these mid level species
are kind of eating a little bit of both, right.
And when we run the statistics on that, sure enough,
we do get significant relationships between traits with the crawling prey
across almost all seasons except for this one,
and then again flying prey across all the seasons.
So there does seem to be a relationship between the traits and the prey that
they're eating.
So there's other traits that I didn't include, but there are a lot of things,
a lot of things we could still test and there's a lot of places we can go with
this and keep continuing asking questions about.
So I didn't look at colour mostly because these, the original ones,
they were exactly the same color.
It was more about the structures on the outside.
So that's why I didn't really investigate color.
And it's hard to quantify color.
And then there's been a couple other papers where they looked at like Purpura
has a lot of different color variation and that doesn't seem to have any effect
on what they eat.
So I avoided color, but there still might be some signaling
there.
Nectar, I mentioned that they have these sugar
stashes, but near the mouth, some species have a lot, some not so much.
So that might be playing a role in what's attracting,
like what kind of prey they're attracting.
So I didn't measure that.
Other these the group together, so this one,
the white top pitcher plant and Serasenia flava, they when you smell this species,
particularly the leaf, it's like it's the leaf.
It smells like a bouquet of flowers.
It smells really strong, like roses.
It's very attractive smell and they tend to get a lot of butterflies.
So I think that is playing a huge role in what they're eating.
This species.
Some people say it smells like cat urine.
I can't really tell that I don't have a cat, so I don't know.
But that one does have a distinct smell and that might be playing a role.
And also what they're eating, which is a lot more like Wasps and bee
species.
And this little red part here that you'll see like sugar glistening on it as well.
So these two have a lot of smells to them, a lot of like floral kind of hints of of
flower smells down here.
This species doesn't really have a smell at all.
Again, this is the low pitcher plant, if you're thinking about it,
they're eating ants.
Ants don't seem to be quite as readily.
You go smelling things like butterflies.
Butterflies have those antennas.
They're really picking up scent in the environment.
So maybe if there's not selection for those floral scents in that species.
So that one doesn't really have much smell and this one smells like green,
green grass that's just been cut.
Again, mid level species, maybe it relies more on crawling prey so
it doesn't need the the smell so much.
But again, these are just four species.
So I've always been interested across all species.
Do we see kind of differences in the sense that they're giving off?
So yes, there does seem to be some prey
specialisation there and there's a lot more questions to ask around this.
So now I'm going to talk briefly about my research that I did during my Masters on
pitcher plant obligate arthropods, particularly a pitcher plant moth.
So we think of their interactions with these plants or like insect interactions
as just prey.
But some of these insects actually make a home and a living inside of the plant
themselves.
So a couple of these species, these two moths,
they live with the pitcher plant.
They live their whole life cycle in the plant.
The.
And it was on the pitcher plants.
So my master's advisor and I sat out in bogs and just watched to see what we find.
And what we found is that the moth will lay an egg about like 2 inches into the
plant in the mouth.
And here's a picture of that egg.
And it takes about 12 days to actually hatch.
It goes through the first second instar larvae.
So they'll shed their skin and get larger.
But what this one does, and it's hard to see here is it chews a
little ring around the inside of the plant and then the the top of the plant
just folds over so it protects it.
It's like in a little cocoon.
So this is what it looks like.
It made a ring and then it sealed it up basically so it can feed in there without
getting eaten by anything else.
So it stays in that for about 12 days.
And there's the tiny little larva.
Then in the 3rd and 5th instar stage, it'll migrate from one pitcher to a new
one, and it starts to look beefier.
It's got these little hairs that kind of stick out, and if you startle it,
it falls into the trap.
But those little.
These sites that were isolated had no none of these like moths there.
There have been reports in the 90s that they were there,
but they've been completely extirpated probably because of how we manage the
bogs.
They burn in the winter instead of the summer, which is usual.
So they've probably burned the bogs and also burned out like that pitcher plant
moth during its overwintering stage.
So these are locations where you have this Saracenia alvidemsis that's only
found in two counties in Alabama and on the other endangered pitcher plant
species, Oreophila that's only found in these
isolated bogs up in North Georgia and North Carolina.
So these moths associates are missing.
So it's kind of begs the question of how are we managing these plants and are we
doing a good job including all of the associates that are with these plants or
is this a healthy community that we're managing?
So that's a little background on their, one of their pitcher plant moth,
like one of the associates.
So overwinters is a larva and it's missing in isolated populations.
So the last thing I just want to say is that in Darwin's time, right,
there wasn't a worry about threatened and endangered species.
But Darwin's time is largely why we have a lot of it threatened endangered species.
They were poaching plants like crazy.
They were collecting plants without really thinking about conservation ethic
around that, right.
And what we're seeing, and I say Darwin's most wonderful plants,
that's what he called the Venus flytrap, the most wonderful plant when we look at
all carnivorous plants.
So this paper said 860 critically endangered is in red,
orange is endangered, vulnerable is in yellow.
So we have quite a few, you know, over 100 or 200 species that are fitting
in this threatened endangered category.
When we look at the different groups, we see Nepenthes,
my the Southeast pitcher plants, a lot of them are endangered or
critically endangered and threatened.
Serasinia, that's the North American one.
We have quite a few.
So we're seeing a lot of concern around these plants being endangered and
threatened.
A lot of it has to do with poaching.
Venus flytraps are heavily poached.
There's basically the the folks in North Carolina won't even let you into the bogs
unless they know you're a researcher because they people have come out with
like garbage bags full of Venus flytraps to sell.
So poaching's a big issue.
Pitcher plants will go out into a bog and there's holes where people have been
digging and selling these plants on various things like Amazon or something
like that.
So that's a big issue, habitat destruction.
So again, these are in nutrient poor habitats that
are wet.
So people will drain kind of change the landscape will drain the bogs essentially,
or nutrient runoff from farms will completely wipe out a population.
Other problems are that these plants need to be in open sunny areas.
So if we don't manage those areas and make sure that there's not trees
encroaching on them because when shade hits these these populations,
they also need full sun that will have an effect on them.
And I just want to end with showing a picture.
This is endless bog in Mississippi, 1979.
So this is my master's advisor's photo.
We went back to this bog that's not managed or owned by anybody.
This is that bog now.
So we see this encroachment of woody sweetgum,
that type of thing completely changed the landscape.
And we're seeing this all over the Southeast.
So now, you know, since Darwin, not only are we interested in the
questions of carnivore, we're also interested in research and
management, right?
So there's been a lot of focus on population genetics,
thinking about how do we conserve populations with genetic diversity.
So these are a couple examples.
My student and I went out and we assessed the Alabama populations 25 years after
the last assessment and there's only like 4 populations that are manageable.
So most of the populations we went to only had two individuals.
So we're seeing this this happen.
And now these are the directions our questions go.
So with that, I just want to acknowledge my funding and
some folks that I worked with on this.
And I'm leaving this open with questions for with this quote from Darwin.
This is one of my favorite ones from So simple A beginning.
Endless forms, most beautiful and most wonderful have
been and are being evolved.
So I'll take any questions.
I have not seen that.
I've only seen them usually like in I don't know if I do.
The only time I, I don't know much about parasitic plants,
but I, I seen them on near trees like I think of
like the Indian pipe one.
I have a friend at she was at Emory, She's now at Berry College.
She used to study parasitic plants and look at how they need fire to like
germinate.
So that was a big thing like if they get this,
the compound that's in fire to germinate, they need that.
So they're in fire, you're prone habitats usually in pine
kind of forest where there's probably more acidic soil,
but I've never seen them in nutrient poor habitats.
Yeah, Yep.
Do you have any tips for drugs?
Because I've tried throwing them before.
I have the solo noise.
I made a nutrient poor.
It's like still put in grows and it's like, what am I?
So I don't have a green thumb with these guys.
But Jeremy, right, you have your plants, so maybe you can comment on that.
So yeah, there are plants up here that he brought
in for us to look at.
So I don't know if you want to comment on that.
I mean, it depends on the species.
There's so many species of Shandu, right?
Some of which need like a deciduous.
They need to be old and some are tropical.
So it really depends on the species that have grown.
You may have got the tropical one and just not given that that winter dormancy
and it dies.
Humidity is big and just distilled water is how I grow all my universal.
Yeah.
And I've heard like, yeah, distilled water is the key because faucet
water has too much stuff in it, like fluoride and all that.
Yeah.
Any other questions?
What happened in the summer?
But because of the way we have like houses nearby and all these other things,
a lot of land managers have decided to burn closer to the winter because it's
just a little safer.
They have to have the right conditions.
Wind, all that kind of stuff has to be a low.
Like there's needs not to be any wind and all that kind of a thing.
So they've been managing the bogs by burning prescribed fires through the
habitats offseason.
So the work I presented about the pitcher plant moth I gave to a bunch of land
managers and they were concerned that they were burning out a lot of the
associates.
So what they do now is they burn parts of the bog and leave parts of the bog open.
So that way like any insects can fly in or like there'll be some population
that's saved.
There's been a movement to burn more in season because it's more natural for the
the plants.
But yeah, it's prescribed fires every three years.
Yeah.
And if they're not like that picture I had was an area that's not managed.
And so if it's not managed, that's that's what's eventually happening.
But you can actually cut down the trees and like get the bog re going again.
A famous example was that a lot of land owners,
they're worried that they'll get their land taken away from them if they have
carnivorous plants because they're endangered.
But plants have a different, like if you have an animal that's
endangered, yeah, that could happen.
But plants, That's not true.
But there was one guy who was worried about it,
so he went and mowed all his pitcher plants,
but it actually had the opposite effects.
And his bog came back really nice because he had mowed down on everything.
So it had kind of the same effect as a prescribed burn.
Yeah.
So yeah, hand clearing is one way.
We can also open up the bog.
Yeah.
That's a good question.
I am not very good with the, the like the actual stuff around the
motility and movement mechanisms.
As I understand it, they open within I think 20 days.
Someone else might be able to speak to that.
And it's just about the the like the ion concentration shifting,
that's how they open back up.
So when you trigger a plant without food, it stays shut for a while.
And they've lost a lot of energy from that.
So that's why they say never to like get them to snapshot without praying them
because it does take some time to reopen back up.
Thanks for a good talk.
I just was wondering just that little moth,
is it a problem here for the future plant?
No, it just hangs out.
Yeah, I know.
It's just there.
It also has the name like the pitcher plant mining moth,
because it's just eating the the plant, but it's it's not doing anything to help
the plant.
There was a question earlier about how much does it affect the plants fitness.
There's been people who've tried to look into that and it's really not clear that
there's a negative effect because they still, they eat the plant,
but they're all their frass or their waste is getting released into the plant.
So they might be reabsorbing the nitrogen.
But these plants usually have like 5 or 6 pitchers on them.
So it's one pitcher that's affected.
But yeah, they're still preventing them from eating.
So.
Yeah, yeah.
Can you hear me if I just.
Yeah, yeah.
So you're you showed two varieties of the same species and you showed a graph that
showed that they were eating two different things and that they had just
like very different morphologies.
Yeah.
Is there any evidence that of speciation?
Are they, you said they can interview, but are they actually doing that?
And is there some kind of like niche partitioning that's happening where the
event, you know, eventually these could be?
Yeah.
So I always love to bring up pitcher plants when I talk about like how do we
define a species in class?
Because plants are hard to define species with because they hybridize all the time.
So these like this genus, so it evolved 3, 000,000 years ago.
That's the estimate.
They can all interbreed, all of them.
So you can create hybrids that are fertile.
So it doesn't fit the like the biological species concept.
So I always like to say that they're kind of on their trajectories.
We're catching them in this point of time where they're probably on these
speciation trajectories, but they're still able to hybridize.
But something still is making them like not as fit as hybrids.
And oftentimes you see hybrids in areas that have been disturbed.
So if a habitat someone kind of like drove a truck through,
you'd see hybrids usually in like the truck tracks.
So it seems to be like they need disturbance for those hybrids to actually
be maintained, but they're still, they're still able to to hybridize quite
readily across all the species.
Yeah.
So there's debate of are there 8 species?
Are there 2 species?
Are there one someone argue there's 46 species.
Like it goes, it's like it's a it's a big group for
people to clump them or split them up.
And horticulturists who love how you can get different varieties so they cross
breed them all the time for traits.
They'll say, oh, there's a hundred different species
because you get all these different traits in the the traps.
But yeah, they all, they all, a lot of them flower at different times.
So that makes it hard for them to to interbreed.
But yeah, the variety, they can readily hybridize.
Yeah.
I have a question about like about about growing these things in captivity.
What are your feelings on doing that kind of thing anyway?
For preservation or for just kind of the purposes of having a carnivorous plant in
the household.
Yeah.
So the question was about it, you know, actually growing these plants,
kind of the ethics around that and also for management.
So a lot of like, like botanical gardens down South.
So you landed Botanical Garden in particular.
They've been collecting seeds from populations with the idea that they would
grow them and then replant them out to these bogs.
So that's what my job was when I was there is that there had been plants
growing.
It takes them a while to get that big.
They're a long lived species.
So there was a like some leukophila though, the white top picture plants,
they got about this big, that was about 10 years of growth.
And we went out and we plant like planted them out in the population where the
seeds were from because the population numbers were dwindling.
So there are people managing and growing them in botanical gardens with the idea
of of replanting them out and trying to get population numbers up.
As far as people growing them for hobby, I usually tell people to make sure you
look at where you're getting your source plants from.
Some sources aren't reputable.
So that's where I usually say like, dig in,
try to find out where they're these plants.
Do they get them ethically or did they go out and poach the plants?
So that's usually what I recommend is when you're purchasing any carnivorous
plant is really look into where the source came from.
Yeah, Mentioned about the Okeefenokee variety
that they were in this.
I think you said they were both in the same swamp.
Yeah.
Are they different areas of the swamp?
Yes, they're kind of in the same, like they're different areas.
So like in the Okeefenokee, you get these little land masses.
Yeah.
So you can take a canoe.
We were on canoes and jumping on these little islands.
They're floating.
And it's kind of scary because, you know, there's alligators everywhere.
And so those are where, like, the tall ones are.
But then you could be 10 feet away on more stable land,
and then you see the smaller ones.
Yeah.
So it seems like part of me thinks it might be a plastic response to the
environment where the way the nutrients are,
something in the swamp is promoting that tall growth maybe,
but also that it's also adaptive in that they get these flying prey when there's
not many ants crawling on those mats.
Yeah.
Do ants get on the mats?
They can.
I've seen them.
Yeah.
We did have some ants in some of the the plants, but mostly was moths.
Yeah.
OK.
I think we're going to close it there.