Zombie ants

Daniel and Kelly talk about the science behind the "zombie ants".

See omnystudio.com/listener for privacy information.

Episode Transcript

Speaker 1 (00:07):
The fungus known as Ohio cortceps may be the most
famous fungus in pop culture right now. I know it's
a lobar, but still it's pretty cool. The Girl with
All the Gifts, The Last of Us and a host
of other books, movies, and video games feature this behavior
manipulating fungal pathogen. But what does it really do? How

(00:29):
do the zombie ants behave? And what do we know
about how the fungus hijacks ant behavior? And Yes, at
the end of the episode, I'll speculate on whether Ofio
coort aceps could jump from ants to humans hijacking or
behavior along the way. Welcome to Daniel and Kelly's Manipulated Universe.

Speaker 2 (01:00):
Hi. I'm Daniel. I'm a particle physicist, and I like
to think of myself as a fun guy.

Speaker 1 (01:05):
You know, Daniel, you have made that joke before.

Speaker 2 (01:08):
It's too good?

Speaker 1 (01:09):
It is, It is good, It's good. I'm Kelly Wider Smith,
and I'm a fun gal.

Speaker 2 (01:18):
And today we're talking about how funguses make us friends,
or make us more fun no, or make us whact
weird and climbed to the tops of.

Speaker 1 (01:27):
Things or something else entirely Yes, how ants get manipulated
by a fungal pathogen, but probably well, wait till the end,
we'll see what we think about people.

Speaker 2 (01:37):
I do like the idea that some of our weird
behavior can be attributed to some part of us that's
not really part of us. You know, that you can say, oh,
that's just the fungus in my brain.

Speaker 1 (01:47):
Yeah. Absolutely. So. When I started my PhD, I was
studying why organisms behave the way they do, so I
was into animal behavior and I came across the Toxoplasma
Gandhi literature, where that parasite that lives in our brains
is a sociated with weird behaviors. And I got absolutely
hooked on this idea that not all of our behaviors
are attributable to our decisions, that maybe it's like a

(02:09):
group effort the person who we end up being, and
that you know, the microbes in our gut influence our
behavior and the parasites in our brain influence our behavior.
And I find this topic totally fascinating.

Speaker 2 (02:20):
But in some sense that's frame because it tells you, oh,
it don't make all my decisions. In another sense that's
terrifying because it's like, oh my gosh, I don't make
all my decisions, and Katrina would probably be like, no,
that is who you are. Your microbes are part of you.

Speaker 1 (02:33):
Yeah, No, I tind of agree with that take. But
one thing that I think is fun is that one
of the big names in the field that studies how
Toxoplasma gandhia impacts human behavior, his name is Yaroslav Flagger.
Apologies for my you know, forever bad pronunciations. He got
into this because he was like, you know, I act
kind of weird, sort of like not like other people.

(02:54):
I wonder if I have a brain infecting parasite. And
he gave himself a test and he did, and this
set him off on the path of like wondering about
how toxoplasmosis is associated with human behavior. It's an interesting question.

Speaker 2 (03:07):
Is it possible to have a fungus in your brain
that makes you eat cookies too late at night? Can
I blame that on somebody?

Speaker 1 (03:15):
Daniel? That is you? No, that's you, Daniel, that's you.
And just for clarification, Toxoplasma gandhia is not a fungus,
but there are a variety of different parasites that can
live in human brains.

Speaker 2 (03:25):
Unfortunately, so if I do have a parasite, it's probably,
like Daniel, stop eating cookies. Those are bad for you
and bad for us.

Speaker 1 (03:31):
Yeah.

Speaker 2 (03:32):
Maybe, Wow, I'm overruling them.

Speaker 1 (03:34):
I don't know that cookie consumption as an implication of
brain parasites has been studied thoroughly, So I don't want
to go on the record.

Speaker 2 (03:42):
It's so easy to get to the edge of knowledge
in biology. Wow.

Speaker 1 (03:46):
Yeah, we're not asking the right questions.

Speaker 2 (03:50):
Why does mainstream biology want to shut this question down?
Kelly hmm.

Speaker 1 (03:55):
Yeah, I don't know, Daniel, not a great question, But
you know, what is a great question?

Speaker 2 (04:00):
Give us a transition?

Speaker 1 (04:01):
Yeah, what is a great question is the question we
asked our listeners.

Speaker 2 (04:05):
What was that?

Speaker 1 (04:06):
That was? What is summit disease? And if you would
like to answer questions for us, send us at an
email at questions at Danielinkelly dot org and we'll add
you to our list. So let's hear what our listeners
had to say in response to what is summit disease?

Speaker 2 (04:23):
Summit disease is an affliction that occurs when you can't
stop hiking to the top of mountains, and it causes
you to neglect the rest of your life. I think
it's a brain disorder that makes you way at dead
bodies on the way up Nepalese mountains. The sickness individuals
get when they are at a high altitude and climbing mountains,

(04:45):
for example.

Speaker 3 (04:46):
I think you're referring to high altitude sickness. Mountain climbers,
when they go up above a certain elevation, can get
lack of oxygen, pulmonary edema, cerebral edema, et cetera. No bueno,
this is a disease a similar to OCD. You have
to walk around adding things together.

Speaker 2 (05:04):
I could be mistaken, but I believe it is when
an avid climber gets the impulsive need to tell the
people around them all of the mountains that they have summitted.

Speaker 3 (05:15):
It seems like summer disease could be when I go
on top of a mountain and my fingers swell up
and I get tired.

Speaker 2 (05:21):
Easier except for way way worse.

Speaker 3 (05:23):
Summit disease is when you, after a really long climb,
get to the summit, and then the mountain gods invade
your brain make you do bad stuff.

Speaker 2 (05:31):
I don't know.

Speaker 3 (05:32):
When you reach the summit of a mountain and you
can't stop throwing up because you're so sick of looking
at mountains.

Speaker 2 (05:41):
I think that's when you're hiking and you've each an
altitude or an elevation where the air gets dinner and
you start to get headaches and funauseous and stuff like that.
So I also would have guessed something that happens to
you at the top of Mount Everest.

Speaker 1 (05:53):
Yeah, that is a totally reasonable answer. We have a
very smart audience, but actually this is something that happens
to insects and not to humans. And I'll also note
that I laughed out loud at the uh you have
to walk around adding things together. It took me a
second to put that together and be like, oh, some
it some it adding, and I laughed out loud. So anyway,

(06:14):
thank you for that moment of revelation there.

Speaker 2 (06:17):
Well, I love this opportunity to dig into the real
science that's sort of underlying some Hollywood myths. You know,
there are these fun stories you hear sometimes in science fiction,
but often these are inspired by actual and really fascinating
on their own stories of what's going on out there
in nature. So tell us, Kelly, what is the story

(06:37):
that inspires all these Hollywood tropes?

Speaker 1 (06:40):
Well, So let's start with what is summit disease. And
Summit disease is a thing that happens to a lot
of different insects that are infected by fungus or by viruses.
And the deal is that either the fungus or the
virus gets an insect to climb high, and then it
gets the insect to stay there instead of like coming
down for the night. And then they like cling in
some way and they stay up high and from that

(07:02):
location they then die and they rain infectious particles down
on their other insects below.

Speaker 2 (07:09):
They like explode.

Speaker 1 (07:10):
Uh you know, explode might be over selling it a little,
but like, so, for example, there's a virus that infects caterpillars,
and caterpillars go up during the day to like eat leaves,
and then at night they usually come down and they
like hide. But this when they're infected by this virus,
they climb up and they stay there and then they
die and they sort of liquefy and they rain virus
particles down on the caterpillars that are below.

Speaker 2 (07:34):
They drip guey infected caterpillar down they do.

Speaker 1 (07:38):
Yeah, what a weather forecast that's oh yeah, cloudy with
the chance of virus soup caterpillar bits. That's right, gross,
But this also happens. There are like quote unquote zombie
flies that are infected by a fungus and they'll climb
up and they'll even like they'll climb up and then
they'll spread their wings out to the side so that
when they die, the fungus can come out of their

(08:00):
back and their wings don't get in the way. And
that one does it sort of like shoots like cannonballs
out of their back down at the like flies below.
And so, oh my gosh, this is a pretty common
strategy you see in viruses and fungus that infect insects
that want to go on to infect more insects.

Speaker 2 (08:16):
It's fascinating because you say it does this so that
this other thing happens, which implies that there's some sort
of high level decision making. But I know it's all
like low level mechanistic blind evolution. So I'm curious to
hear how all that comes together and how the whole
process comes together. You know, it's one of these examples
of like a complicated thing where you need lots of

(08:38):
pieces all together to accrue the benefit, which always makes
me wonder how it came together in the intermediate stages.

Speaker 1 (08:44):
Yeah, and this is why the zombie ant system is
one of my favorite systems to study. So this phenomenon
where some parasite or pathogen hijacks the behavior of its
host so that the host is doing something that benefits
the parasite, we call this manipulation, and it's really tempting,
and we've talked about this in other episodes. It's really
tempting when you see a host behaving weirdly to be like, oh,

(09:07):
that's a manipulation that must benefit the parasite in some way.
But while it's easy to come up with a story,
it's harder to test that. And every once in a
while we'll have a story where it sounds like the
pathogen was benefiting, but when you look into it, it's
not so. Mosquitos when they're infected by malaria, right after
they get infected by malaria, they bite less, and there's
a period where after the mosquito takes a blood meal

(09:29):
that has malaria, that malaria is sort of maturing and
can't transmit yet. So if the mosquito took a blood
meal and got slept by a hand, then the malaria
would die, and so that wouldn't be good. You know,
in a very anthropomorphic way, the malaria quote unquote doesn't
want the mosquito to get killed or to take blood
meals at that point.

Speaker 2 (09:49):
While it's still developing and preparing.

Speaker 1 (09:51):
That's right. But once it's ready, once it's in the
mosquito salivary glands and could transmit to a human, those
mosquitos start biting even more. So this was thought of
as manipulation. The parasite is protecting the mosquito and itself
until it can transmit, and then once it transmits, it
gets the mosquito to bite a lot more. And that
really sounds like it would be good for the mosquito.

(10:13):
It's a good story, it's a great story. But it
turns out that if you activate the mosquito's immune response
by for example, killing bacteria and then putting those dead
bacteria into the mosquito, it will do the same thing.

Speaker 2 (10:27):
Even though it doesn't benefit that bacteria.

Speaker 1 (10:29):
That's right. Where Yeah, the bacteria are dead, they're just
making the mosquito's immune system activate, and this is what
the mosquito does. So it could be like when the
mosquito's immune system is activated, it just kind of wants
to hunker down. It's not as fast, it's feeling kind
of crummy. It's just taking a nap before it's ready
to go again. And so that's probably not manipulation. It
doesn't look like the malaria is doing that. That's something

(10:51):
that's driven by the mosquito.

Speaker 2 (10:52):
Could still be in response to the malaria. Right when
it gets infected, it does this, and the malaria can
benefit from it. You're just saying it's not something that
the malaria has specifically engineered to benefit itself. It's something
the mosquito is already doing or would otherwise have done.
Fascinating exactly.

Speaker 1 (11:08):
Yeah, So trying to figure out who's driving the change
in the behavior and how it actually benefits is much
harder than coming up with the initial story. Yeah, and
so what I love about the zombie ants is that
this system has been studied in quite a bit of detail,
and so we're actually starting to nail down the various
pieces of what's happening here.

Speaker 2 (11:24):
Well, that reminds me of our conversation with Capo hen
and when we were talking about science and storytelling and
how much of science is storytelling is saying this happens
because of that, because of this other thing, and sometimes
the statistics or the mechanics of it don't always support that.
It's just we are trying to extract stories because stories
make sense to us.

Speaker 1 (11:43):
Yeah, and I think sometimes we get a little carried
away with our stories and we don't necessarily have facts
to support every piece of the story. And so this
system is nice because almost every piece of the story
has been dug into to some degree.

Speaker 2 (11:57):
All right, then carry us away to a story, Kelly
tell us about manipulation of ants.

Speaker 1 (12:02):
Okay, you are a little ant walking around on the
forest floor. Unbeknownst to you, you have stepped on a
fungal spore. The fungus gets in between the cuticles and
invades the body.

Speaker 2 (12:15):
Wait, I'm a little ant and I have cuticles still exoskeleton.

Speaker 1 (12:19):
I think they call that cuticle. I don't study ants.

Speaker 2 (12:21):
Man. What's the name of my aunt? Am I Dantiel?

Speaker 1 (12:27):
Yes, yes, you're Danchel.

Speaker 2 (12:29):
Walking around the forest with my little cuticles.

Speaker 1 (12:31):
Okay, so poor Danchel has picked up a fungus. Danchel
doesn't realize that he's infected. Actually, if you're a forger,
you're probably a female. So this anyway, this is not
working great. But anyway, so the little ants, the little
ant has gotten infected, doesn't realize it. It goes back
to its nest. The nest mates don't seem to realize
that it's infected either. But a couple weeks after it

(12:54):
initially gets infected, it starts walking out of the nest.
And this nest is up in a tree, and it
starts rumbling down. We call it a drunk walk. So
it sort of starts stumbling down the tree and then
it walks along the forest floor and it climbs up
a stalk and this is in the tropics. It climbs
up a stalk or a stem of something to about
twenty plus or minus two centimeters. This is happening at

(13:16):
solar noon and on the north northwest side of the plant.
It goes underneath a leaf, bites down with its mandibles.
These are like the pinsy mouth parts it has, and
then it will never move again and it dies.

Speaker 2 (13:28):
Wow. So it has to go all the way down
the tree just to find the stalk to climb up.

Speaker 1 (13:32):
Yes, yep, just to find the stock to climb up.

Speaker 2 (13:34):
Fascinating.

Speaker 1 (13:35):
And then the ant dies and a stalk comes out
of the side of its neck and it forms a
ball at the sort of like top ish part of
the stalk, and then fungal spores rained down on the
forest floor and the cycle starts again.

Speaker 2 (13:48):
The stalk is not from the plant, it's some like
weird fungal thing.

Speaker 1 (13:52):
Yeah, it's the fungus makes it so the fungus, now
that the ant is dead, it starts using all of
the ant's internal body parts and converting it into fungus
and makes this stalk that rains fungal spores down, and
the cycle starts again.

Speaker 2 (14:03):
This sounds like a science fiction horror movie. You're telling
me this is happening on our planet all the time.

Speaker 1 (14:08):
Oh my it is. And okay, so what blows my
mind is that that is so specific. Like one of
one of Zach's gripes about me as a human being
is that I am really bad at estimating distances, and
like He'll be like, well, what's you know? Do it
about two feet from here, and I'll be like, I
have no idea what you mean, Like, I just I
can't do that. Whereas this fungus by remote control is

(14:30):
getting the ant to about twenty five centimeters plus or
minus like two and a half centimeters. I think earlier
I said it was twenty but it's more like twenty five,
which is very specific. And so how does that happen.
We're gonna get to our best guess right now at
how that happens a little bit later in the show.
But it's amazingly specific.

Speaker 2 (14:47):
Wow.

Speaker 1 (14:48):
But now it's worth mentioning that. Okay, that is a
story from O fio cordus steps unilateralis And just to
complete the.

Speaker 2 (14:55):
Loop, it rains it down on the forest floor and
then the next ant can come along and pick it
up in there goals and that's how it completes the cycle.

Speaker 1 (15:02):
Danchel, the she ants does pick up dante l Yeah, Dantel,
that's right, picks up the fungus and the cycle starts again.

Speaker 2 (15:09):
Wow, all right, okay, And so the name of this
fungus is some crazy Latin phrase. Yeah.

Speaker 1 (15:13):
So Ofio cordyceps unilateralis. The unilaterallysis refers to the fact
that the stalk comes out of one side of the
ant's head. And so opio coortceps is a genus. So
there's a lot of different fungus species that are very
closely related, and they infect different ant species, so they
seem to specialize on different species. So there's actually a

(15:34):
bunch of ants all over the world that are infected
by this fungus in slightly different ways. So the story
isn't the same for all of them. The story I
gave you is a story that I'd initially read for
Ophagio Cordyceps unilateralis infecting an ant species in the tropics.
But yeah, there's a lot of this happening in our world, and.

Speaker 2 (15:52):
Within this species of ant and this species of fungus.
You're saying, there's not a lot of variation in the
behavior of ants. They like basically all do the same
march to death and then brain.

Speaker 1 (16:02):
Explosion, brain explosion or you.

Speaker 2 (16:04):
Know, fungal stock extrusion or what.

Speaker 1 (16:06):
Yeah. Yeah, So we are going to talk about how
they differ a little bit. The details can differ depending
on where you are, but the story is generally the same.
That they find a way to be up above the
areas where the foragers usually go so that they can
rain the spores back down.

Speaker 2 (16:21):
Again. Wow, amazing, So tell us how it works.

Speaker 1 (16:24):
So first, I want to note we call these zombie ants,
and I often get people in the field grumpy with
me for calling them zombies because they're like people are
gonna think they come back from the dead. Dear listener,
I don't think that you think that ants come back
from the dead. But just to be clear, the zombie
ants do not come back from the dead. They are
their behavior is getting hijacked while they're alive, and then

(16:46):
they die in a very particular position that benefits the fungus.

Speaker 2 (16:49):
So you're saying they're not zombies because the ants haven't died.
They're just in some sort of like controlled state where
they're not really acting the way they would if they
were normal ants. They're like drunk or they're hallucinating or something.

Speaker 1 (17:03):
Something like that, and yet it looks like their circadian
rhythms are getting messed with. So Terarissa de Becker's lab
has looked at how a big part of the manipulation
seems to be them doing kind of normal behaviors but
at abnormal times.

Speaker 2 (17:15):
So that seems to me a very technical definition of zombie.
I mean, if humans, for example, were infected by something
which made them stagger around and want to eat brains,
but weren't technically dead, would you be there being like,
excuse me, you're not a zombie.

Speaker 1 (17:28):
Sir, No, Because I love fiction in all of its forms,
and as long as the rules are consistent in the
world that's created, I don't care. So when I use
the word zombie, I basically just mean an organism where
a significant amount of its behaviors seem to be under
the control of another critter, and those behaviors are good

(17:48):
for the parasite but usually bad for the host.

Speaker 2 (17:51):
All right, well, let's take a break because I definitely
need one, and come back and hear all about the
details of how this fungus controls this an. Okay, we're back,

(18:20):
and we're talking about the name of a fungus that
I cannot pronounce but is amazingly adept at manipulating ants.

Speaker 1 (18:27):
This is a really nice like turn of the tables.
Usually I'm the one who can't pronounce things. We've got
to do more episodes with like complex latinate names. But okay,
So one of the first things I think is so
amazing about this system is that it evades the social
immune system that ants have. So ants are very genetically

(18:49):
related to one another, and they work together for this
common goal of like helping the queen create more offspring
and stuff like that.

Speaker 2 (18:55):
And they have complex fractional relationships, right, It's not just
like you have kids that are half you. You're like
related by a quarter or a sixth or a third
or something complicated. Right.

Speaker 1 (19:04):
I think it's like three quarters. Like you're way more
closely related than like, you know, my brother and I
would be, for example, typical siblings, and so they're like,
you know, pretty close to you genetically. And so this
tends to result in what look like ultruistic behaviors. And
so if one of the ants comes into the colony
and is clearly infected with something, the nest has a

(19:27):
like social immune response where other nestmates will be like, oh,
you can't bring that in here, man, and they will
in some cases kill that ant and then go put
it in like a graveyard somewhere far away from the
nest so that it can't infect the rest of the.

Speaker 2 (19:41):
Nest based just on the behavior. It's not like it's
giving off some pheromones or something.

Speaker 1 (19:45):
I think in a lot of cases we don't know
exactly how the nest mats can tell. It's probably some
combination of behaviors. And then ants are a species that
in particular tends to communicate a lot with chemical cues.
So it could be that they sort of smell or
whatever taste and nestmate and they're like, no, that's it's weird.
We're kicking you out, Daniel.

Speaker 2 (20:03):
You taste funny. We're killing you.

Speaker 1 (20:05):
Yeah, that's right, that's right, Daniel. It's not how your
forehead is supposed to taste. And I licked it and
now you can't live here anymore. Danchel, danchel. And so anyway,
so usually when an infected nest mate comes back, it
gets picked up on and they get killed and kicked out.

Speaker 2 (20:21):
Brutal but fair.

Speaker 1 (20:22):
Brutal but fair. And this is a pathogen that you
would want to put a stop to. So you know,
if they don't capture this individual and kill it, it
is going to create essentially like a stock of infectious
propagules nearby. So anyway, there should be selective pressure for
this part.

Speaker 2 (20:38):
And so how does it evade this selective pressure? Why
can't the other ants tell?

Speaker 1 (20:42):
So we don't have a great handle on why the
other ants can't tell. Part of it seems to be
that in at least some systems. So I'm going to
be talking about this system like every system acts the
same way, but just sort of like with the tartar grades.
Some questions have been asked in one ophiocordycep species infecting
one ant species. Some questions been asked in other systems,
but we're going to mix and match for the purpose

(21:03):
of this show. But there's the disclaimer. So some ants,
the timing of their behavior changes and they interact with
nestmates less often, and so part of the story might
be that instead of just like blindly going into the
nest and then getting found out, these ants that are
infected are avoiding nest mates so they never get found out,
they never get their forehead licked, and so so they're

(21:25):
able to escape in that way. It could also be
like the scent of the fungus is being masked in
some way, but through mechanisms we don't understand, it manages
to evade the social immunity of the nest.

Speaker 2 (21:35):
Wow.

Speaker 1 (21:36):
Amazing, Yeah, pretty cool. All right, So now you've got
this ant that's infected. It's nest mates haven't killed it
like they probably should have, and then at some point
it's does that Drunkard's walk, and we don't really understand
why that drunkard's walk happens. But there is a chemical
that's produced by the ant that is associated with something

(21:57):
that causes like staggering and seizures and other insects. And
so we think that it's going out there and it's
starting to do this staggering thing because of some chemicals
produced by the fungus. It gets down to the forest floor,
and now the interesting question is how does it know
where to go? So this is the Summit disease part.
It starts climbing up, but we're trying to figure out
how does it know where to stop? How does it

(22:18):
know where a good spot is.

Speaker 2 (22:20):
Well, it's very confusing to me that the behavior is
so complex that it includes climbing down and then climbing up,
Like I could see it somehow is pulling on some
lever inside the brain to make it go up, to
make it go down, but to make it go down
and then up like that's really amazing.

Speaker 1 (22:37):
That is really amazing. I mean, I think part of
the selection pressure there. And this is just me telling
a story. I haven't I don't know that we've tested this,
but if the ant had gone down, it's probably one
going down a big trunk, and they tend to attach
to like thin stems, and we'll get into that in
a second. But also if it just kind of clung
in an area where foraging ants would be going up

(22:58):
and down. Anyway, if a four ant sees a dead
ant with a stalk coming out of its neck, that
it is going to throw over into the trash can,
and so that would be the end for the fungus too.

Speaker 2 (23:09):
So that tells us why that strategy, the simpler strategy
wouldn't work of just like clinging to the tree. But
it leaves us still impressed with this complex strategy of
climbing down and then climbing up.

Speaker 1 (23:19):
Right, And so let me go ahead and jump ahead
a little bit to the benefit of climbing back up again.
So there's been an experiment done where they took ants
that had like settled in at a particular location and
they cut the leaf off that the ant was on
and they moved it up. And when you move it up,
the temperature and the humidity are no longer good for
the fungus, and the fungus can't make that stalk and

(23:41):
it can't make the infectious propagules that rain down on
the other foragers, and so there is this like kind
of narrow band that the fungus needs to be in
in order to complete its development. And so you know,
it takes some work to find exactly the right spot.

Speaker 2 (23:56):
And it's fascinating to me to imagine all the evolutionary
dead ends. You know, ants that just went down and
never climbed up, ants that climbed up the tree instead
and didn't propagate. It's incredible that this whole thing came together.

Speaker 1 (24:09):
Yeah, yeah, it really is well, and I'm sure that
a lot of times when researchers go out to study
this kind of stuff, like you know, if you're too low,
then spiders and other scavengers come along and they'll eat
the zombie ant. And so there's probably some instances where
the ant dies and the wrong spot, but the researchers
never find it because something is eating it and it's gone.

(24:29):
So you know, you do the best you can with
the data you've got.

Speaker 2 (24:32):
So tell us about this climbing up. How does it
know where to stop that it gets this right height? Like,
do we understand the mechanisms for how it knows how
high it is. It's not like doing GPS or something.

Speaker 1 (24:43):
So we think it's queuing in on light, which is
amazing to me because it's inside the body of an ant,
and so how is it getting information about light? So
what they did was they found what's called ant graveyards,
So the ants tend to accumulate in certain areas of
the and so they're like, Okay, we know this is
an area that's good because the fungus have chosen to

(25:04):
be here before. And then they put a little bit
of a light shade over the zombie graveyard and so
now that area is getting a little bit less light
than it was getting before. And what they found was
that if you go back in future weeks, that area
doesn't get as many new ants as nearby areas that
have more light. So it looks like the fungus is
driving the ants towards areas that have certain amounts of light.

(25:27):
And then they looked there were still some newly infected
ants that went into the areas with the shades, and
if you followed what was happening with that fungus, overtime,
the fungus was less able to produce those stalks and
produce I'm just gonna call them baby fungus because no
one wants to hear me try to say propagule again.
So less baby fungus gets made in areas where you've

(25:48):
got these shades, I see.

Speaker 2 (25:50):
And so the ants are using the light as a
queue for where to go. Is the light important in
making the baby funguses or is it just like a
signal to the fungus of when the ant has crawled
up to the right height.

Speaker 1 (26:01):
I think that the light is used as a proxy
for information about temperature and humidity. And it could be
that the light is important for some way too. I
don't a fungus. I don't know, but nature's complicated, but
it does look like things like temperature and humidity and
light are all important for the way the fungus is
able to develop.

Speaker 2 (26:19):
Wow. Fascinating.

Speaker 1 (26:20):
And this is the part that you see another insects too.
We I talked about those zombie flies and those caterpillars.
This climbing up thing happens in a lot of insects systems.

Speaker 2 (26:30):
And then you said they also bite down, they like
clamp onto this plant. Why is that part important? Is
it because the ant's going to die and you want
it to stay there.

Speaker 1 (26:37):
Yeah, so you want the ant to stay put. And
so in the tropics, what happens is they find a leaf,
they crawl along the bottom of the leaf, along the
major leaf veanes, and the ants will clamp down with
their mandibles. They've got these pincers and their muscles will
like hyper contract, so though like really strongly bite down,
and then the ants will never be able to open

(26:59):
their mandibles again and they will die there.

Speaker 3 (27:01):
Wow.

Speaker 1 (27:02):
And so that's how they hold on. And this is
called the death grip. And one of the things that's
interesting is that depending on where you are in the world,
the death grip will look a little bit different. So
in the tropics they tend to bite down on leaves,
but if you go to like North Carolina, for example,
instead of biting down on leaves, they'll bite down on stems,

(27:23):
and they'll also wrap their legs around them, and so
they'll hold on with their legs and with their pincy parts.
And we think that the reason that they hang out
on stems instead of leaves in areas that are farther
north like North Carolina, is because in the tropics, leaves
really never fall off the trees, or they at least
don't have a seasonal pattern of falling off in the winter,

(27:45):
whereas farther north, if you bite down on a leaf,
you've got until like I don't know, August, September, or
October before those leaves start to fall off. But if
you're on the stem, then you can stay up there
for longer, raining fire down upon the other ants. And
so it looks like there have been four different instances
where you've gotten this evolutionary transition from biting down on

(28:07):
leaves to biting down on things like stems.

Speaker 2 (28:10):
This is fascinating. I love these moments in science when
you can look at what's going on and unravel it
and tell a story. I remember Hazel summarizing all of
science once. She says, like, stuff happened and we figured
out why, And I'm like, yeah, that's pretty much the
whole idea. Yes, So by looking at this pattern of

(28:30):
how things evolve differently in different parts of the world
where the conditions are slightly different, we start to get
a sense for how this all came together. That's incredible.

Speaker 1 (28:38):
Yeah, it's really incredible. And I got to see one
in North Carolina. I'll put a picture on this online
when it comes out. But we found one in North Carolina,
and Andrew Turner found it. I was out looking for
snakes and salamanders. And Andrew Turner, a friend of mine,
was like, is that a zombie at And I freaked out.
Anyone in like a one mile radius probably her me

(29:00):
screamed because I didn't think I was going to get
to see a zombie ant. So anyway, I've seen them
in North Carolina. And then Andrew Turner put one in
like a resin for me, and so I've got it
on my desk and it is my favorite.

Speaker 2 (29:10):
And what are we looking at?

Speaker 1 (29:11):
We are looking at this is a bit of stem
and on the bottom there's an ant that's got its
legs wrapped around the stem. It's biting down with its mandibles.
You can see it's got a big stalk coming out
of the side of its head. The spore that the
fungus would come out of is kind of small. It's
hard to see, but it's about maybe three quarters of
the way up the stem. Best thing I own.

Speaker 2 (29:35):
You have children too, don't for care.

Speaker 1 (29:37):
I don't own them. You know, they could choose to
leave at one point, but this will never leave.

Speaker 2 (29:46):
It's a special place in your heart. It is all right.

Speaker 1 (29:49):
So the ant bites down. And one of the cool
things about this, what we call a death grip, is
that it leaves a very distinctive mark. So if you
find leaves, you'll see the they've got. It looks like,
you know, like scissors cut on either side of the veins.
And there are forty eight million year old leaf fossils

(30:09):
from Germany that have these little scissor cuts in them,
and we think that these are like essentially fossil records
of behavior showing that like around the time a bunch
of the different mammalian species we're sort of evolving into existence,
this manipulation was already happening. And you know, you can't
be one hundred percent sure the ants weren't still attached
or anything like that, but it's indirect evidence that this

(30:32):
is sort of an ancient association and a manipulation that's
been going on for longer than humans have been on
this planet.

Speaker 2 (30:38):
And so when the ant mandibles do this hyper contraction,
they make a special sort of pattern that they can't
otherwise make because it's just the ant mandible, right, It's
not like, how is this pattern different from a normal
ant chomp.

Speaker 1 (30:49):
So, first of all, a lot of ants don't chomp
around leaf veans like this, So you might be thinking
about leaf cutter ants, and leaf cutter ants will cut
out like chunks of leaves and bring them back to
their net so that they can they feed them to fungus,
and that they're sort of like a farming situation. But anyway,
ants don't usually just go and like chomp down on

(31:10):
leafs around the veins and then do nothing else with it.

Speaker 2 (31:14):
I see. So it's also the location of the chump.

Speaker 1 (31:16):
Yeah, it's also the location of the chump. Wow, amazing, Yeah,
pretty cool. And so you tend to get aggregations in
these good parts of the forest where the conditions are
good for fungal growth, and so you end up with
these ant graveyards where you've got a bunch of these
zombified ants hanging on the underside of stems or leaves,
raining fungal spores down on their nest mates below.

Speaker 2 (31:38):
And does the fungus actually kill the ant or does
this sort of death march end up exhausting the ant
or why does the ant die?

Speaker 1 (31:45):
I don't know if the ant dies, because once it
bites down, it can't use its mandibles again. I don't
know if it just eventually dies because it runs out
of energy, or if the fungus kills it, but I
do know that pretty soon after it bites down, the
fungus starts consuming the inside of the ant to make
more fungal tissue instead.

Speaker 2 (32:02):
And how long is it like spraying propagules.

Speaker 1 (32:04):
For That really depends on where you are. I think
in some parts of the world it happens for like
just a couple months. I think in some areas, I
think it can happen for like a year. That really
depends on the environment that you're in.

Speaker 2 (32:17):
All Right, and let's take a break, and when we
come back, we'll hear about how this benefits the fungus
and how the ant manages to pull this all off. Okay,

(32:45):
we're back, and we're talking about the death march of
zombie ants. Kelly, tell us why the fungus makes this happen.
Why can't the fungus just find some other friendlier way
to spread itself.

Speaker 1 (32:57):
I don't know why it doesn't find a friendlier way
to do it, but we do know that this method
seems to work for the fungus. As we sort of
hinted at earlier. It's actually pretty easy to move these
ants to different places to test out, like where would
the best place be for these ants to have settled down,
so you can cut off a leaf, And if you
move it up too high, as we mentioned earlier, the
temperature and humidity and lightning conditions are just not good

(33:20):
and the fungus will essentially never be able to produce
that stock that makes the spores. And so that's the
end of the line for the fungus. Not great. And
if you move it down too low, it gets found
by scavengers. And so unlike a lot of other examples
where we have a nice story, here we've been able
to manipulate the system a little bit and say, you know, look,
if you do something different than what we're seeing, the

(33:41):
fungus is quite clearly doing less well. The fungus either
gets eaten and killed or it can't make babies.

Speaker 2 (33:46):
I'm still sort of amazed that this whole thing works,
Like I can imagine a fungus infecting an and and
it makes a small change in the ant's behavior, and
maybe that benefits it a little bit, But this benefit
requires such complex behavior for the antigodam and then across
and then up and then bite and all this stuff.
All these pieces have to basically fall into place due
to random mutation. So how do you get all the

(34:08):
way to this complex behavior when none of the individual
pieces on their own are going to benefit the fungus.

Speaker 1 (34:14):
Yeah, that's a great question. So one thing that's worth
noting is that, you know, as we've mentioned earlier, this
summoning disease thing happens pretty often. So it suggests that
there's something about insects where it's not too hard to
manipulate their ability to go up or stay up. And
so a number of different kinds of parasites and pathogens
have found the switch. I can't say I'm an expert

(34:34):
on what that switch is, but there's a couple of
different routes to up and stay there. But you can
imagine that this happened, you know, step by step. So
maybe the first thing that happened was that ants that
were starting to show signs of being infected by the
fungus left the nest so that the nestmates didn't kill them,
and maybe they died on the forest floor. And then
there happens to be an ant that climbed up a

(34:56):
little bit before it died, and that helped the fungus
relative just dying on the floor. And so you can,
you know, imagine how each step could have happened first
and then been honed over time. But this is definitely
one of those things where we have to tell a
story and we can't be exactly sure what happened in
what order. I mean, maybe what happened first is that

(35:16):
the ants that are infected by a fungus would die
high up and they'd never go back to their nest.
And maybe the nest stuff came later by some ant
that happened to wander back but wasn't discovered for whatever reason.
And so you know, each step there's selective pressure for
whatever benefits the fungus more. But the exact path that
this took. I think the best we can do is speculate.

Speaker 2 (35:36):
I see. But it's plausible to string these complex behaviors
together because each individual one already does benefit the fungus.
So that, yeah, that makes sense. I wonder what in
one hundred million years, this fungus will have this ants doing, like, oh,
it turns out if they do the macarena before they
bite down.

Speaker 1 (35:55):
Yeah, yeah, it could be. I mean I would imagine that, like,
as climate is changing across the planet, the exact location
where biting down is the most beneficial might change. So
there might be selection to like tinker with exactly where
the ants end up so you keep getting the right
temperature in humidity, and maybe that will be like you know,
you should go to areas with even less light because
everything is getting too warm and too hot, and so

(36:16):
less light will be a little cooler and the temperatures
will be right anyway, So I can imagine that happening.
But part of understanding the steps is probably understanding the mechanisms,
because that gives you some insights.

Speaker 2 (36:28):
Yeah, like what's going on inside the ant that lets
the fungus? What are these levers that the fungus is pushing?

Speaker 1 (36:34):
Yeah, so first let me just talk briefly about how
we start answering these questions. So, as we've discussed, there's
a bunch of different steps here that the fungus is doing,
and so the answer for how does the fungus manipulate
behavior probably differs depending on what step you're talking.

Speaker 2 (36:50):
About different ants, different answer.

Speaker 1 (36:56):
Do I tell you often enough? How much I like
working with you, Daniel, because I really do.

Speaker 2 (37:01):
I'm just going for the easy puns because somebody has to.

Speaker 1 (37:03):
I know, the dad jokes, the amazing dad jokes. So
the way that you know, for example, if you're trying
to figure out what differs between an ant that gets
ignored by its nest mates and an ant that gets dumped,
well you can, for example, infect some ants with ofio
cordyceps and other ants with a different kind of fungus
and send them both into a nest and see how

(37:26):
they interact differently with their nest mates, how the nestmates
interact differently with them, And then you can look at
the different chemical profiles and say, like this one is
emitting these chemicals and this one is emitting these chemicals,
and then try to figure out, you know, is the
fungus is ofio cord aceps producing some chemicals that the
other fungus doesn't produce, and then start looking into those

(37:47):
as candidates for what's happening there.

Speaker 2 (37:49):
Do you need an IRB for these kinds of experiments
or can we just experiment willy nilly on ants? Do
ants have any rights?

Speaker 1 (37:56):
That's a good question. So IRBs are almost exclusively for humans,
so you don't need an You.

Speaker 2 (38:00):
Can't just experiment on dogs and chimps and rats, right,
there's some ethics there, yep.

Speaker 1 (38:05):
For dogs and chimps and rats, you need an institutional
Animal Care and Use Committee protocol and you have to
jump through many hoops to make that happen, which which
we'll talk about on another episode. But for invertebrates like ants,
you don't need to do those kinds of protocols. But
I will say that everyone who I've ever talked to
who works with animals, even just little ants, gets pretty

(38:27):
emotionally attached to them, and they do worry about, like
how do I euthanize this ant to get my data
in the way that will like make it fastest. And
you know, I don't think we really know if ants
feel pain or not, but like, if they do, how
could we do it so that they'll feel the least
amount of pain?

Speaker 2 (38:42):
So nobody's just callously grinding up ants. They're like shedding
a tear while grinding up ants. That's nice.

Speaker 1 (38:48):
Yeah, let's move on.

Speaker 2 (38:53):
All right, No, but I mean jokes aside. You're saying
that scientists involved understand the costs here in terms of
lives and the appearances even of the little ants, and
that's nice.

Speaker 1 (39:02):
Yes, no, they do, and I think they try to
make the ants lives as natural and as nice as
possible before these experiments happen. But so mostly the point
I wanted to make was how we do these different
comparisons to get a handle on what might be happening.
And the answer is, you know, at very similar time points,
you look at ants that are uninfected, ants that are
infected by opiel cordyceps, and ants that are infected by

(39:24):
other fungus that are bad for the ant, but we
don't think they manipulate behavior in any way. And by
looking to see what's happening differently in the bodies and
the behavior of the ants in those three different categories,
we can start getting some like candidate molecules for you know,
this might be the thing that's getting produced by the
fungus to change the behavior. And so they found a

(39:46):
lot of stuff that differs, and that's not too surprising
because the ants are doing complicated behaviors. There's a lot
of behaviors. I feel like what we really want as
humans is that the answer is there's this one molecule
that tells you everything, and that's fascinating, but really it
ends up being like hundreds of molecules that are being
produced that we think are important in every single different step.

(40:08):
So there's not like a really nice, easy to tell story.
But a couple things that pop out is that interra
toxins seem like they're important. These are toxins that are
released by things like bacteria like E. Coli. We're not
totally sure what the toxin is doing to the ants,
but it might be playing a role in breaking down
ant muscles at particular times. So maybe after the ant

(40:30):
bites down, those muscles get broken down so the ant
can't leave, and that might be what the toxin is
doing when it's released at that point.

Speaker 2 (40:37):
I think it's great to try to dig into the
details and understand the mechanisms to make sure the story
that we're telling is the real story, and also because
you could discover surprising things when you dig into the details.
But what else could we learn by doing this. Is
there the possibility here of a surprise that we discover, Oh,
it's not actually working the way that we expected.

Speaker 1 (40:58):
Yeah, So a lot of people think of the behavior
manipulating parasites and pathogens as like evolutionary neuroscientists. So they've
been interacting with their host for you know, in this case,
it looks like more than forty eight million years, and
through the process of natural selection, they've maybe happened upon
solutions for changing the ants behavior. And so by looking

(41:19):
to see what is the fungus making, if it's a
compound we've never seen before, maybe we've unlocked some tiny
piece of the puzzle for how brains work and how
you can modify behavior. And you know, you could imagine
maybe if you've got some pest in a field, if
you make them all like you know, climb up and
stay up and then die, they'll like stop messing with
your field. And so like, whenever we can understand even

(41:40):
how insect behavior works, it gives you some extra tools
to not just you know, understand how your world works,
but also to maybe sort of control some of the
negative aspects of like pest organisms.

Speaker 2 (41:50):
Wow, so the fungus has been doing neuroscience experiments on
the ants for forty eight million years without ever writing
a paper and getting their PhD. That's got to set
some kind of record.

Speaker 1 (42:00):
They don't have to worry about tenure. They don't have
to get brands, they don't have to write permits and protocols.
It really seems unfair the head start that they've gotten.
But if we study them, then we can sort of
extract their secrets and maybe this will help us like
jump ahead in our you know, study of neuroscience, which
I think is a cool idea. And so they also
found what they call a bioactive compound where they've they've

(42:21):
never sort of seen this before, but it looks like
another compound that, as we talked about earlier, causes insects
to stagger, and so this might explain why they sort
of like walk down the tree like they're drunk. But
we think, and this is this is just hypothesizing at
this point, we think it might be important in those
systems where the ants are clinging to the bottom of stems.
If the ants are feeling like all sort of wobbly

(42:42):
and uneven, they might hug down on the stem to
hold themselves so they don't fall off of it, and
that could be sort of the moment that the fungus
kills them, so that they will be really clinging hard
to the stem. And at this point. This is just
a story, and we know that we need to dig
into it more. But that's where we are right now.
So it's complicated.

Speaker 2 (43:02):
And do we know like where in the ant the
fungus ends up, Like does the ant have a little
ant brain and the fungus is sitting on top of it,
like cackling maniacally and pulling levers.

Speaker 1 (43:12):
Yeah, so this is really neat. So you know, I've
already mentioned that Terissa de Becker's lab has been doing
some important work on timing, and they've been working on
like chemicals that are produced by the fungus. David Hughes
did some work with collaborators where they scanned ants with
an electron microscope, so like very very detailed scans, and
they put all of the scans together and what they

(43:33):
found was that the fungus is forming a network and
it's invading a bunch of different muscles. And so the
way it was described in the popular press was that
you could think of it as like the fungus essentially
having strings on a puppet, where it could be like
pulling up and down, and that might be over selling
it a little bit, but one of the things that
they thought was interesting was that it doesn't seem to

(43:54):
be invading the brain tissue, so it's touching the brain
but not going into the brain tissue. This was made
a pretty big deal in the POPSI articles at the time.
I wasn't as impressed with that. So, like the brain
infecting parasite that I studied on fish for my PhD
also sat on top of the brain and not inside
of it. And there's some other evidence in the zombieant

(44:15):
system that the fungus is kind of protecting the brain.
So you can imagine that, like if you're inside of
the brain, you might just like totally screw up your ride,
like it's not gonna do what you want, because you've
just totally debilitated it. And now it's obvious and the
other ants can tell. And so it looks like it's
sort of tinkering with the brain without actually like sticking
its hands in there. But it does have its you know,

(44:38):
hipha which are like fungal fingers inside the other muscles.

Speaker 2 (44:42):
Wow, amazing, and I see something amazing here in the outline.
Tell me about hyper parasites. Are these like the superhero
version of parasites? Kind of were they bitten by a
radioactive spider.

Speaker 1 (44:54):
No no, no, no, no, you've watched too many movies, Daniel.

Speaker 2 (44:58):
This is true.

Speaker 1 (44:59):
Yeah, this is cool. So you know, you've got this
fungus that manipulates ant behavior. But there are other fungal
species that infect opio cordyceps. So the ant will be like,
you know, clinging to a stem, and you'll find fungus
that is living on top of Ofio cordyceps and is
sapping the o fio cortaceps energy.

Speaker 2 (45:18):
It's like fungus inception. Wait, fungus antception.

Speaker 1 (45:23):
Whoa dead jokes galore. This might be our most dead
jokey episode. Yet I didn't see it coming.

Speaker 2 (45:29):
Wow. So this fungus thought I was pulling the strings,
but its strings were being pulled the whole time.

Speaker 1 (45:34):
There are so many levels in nature. I am so
glad to be uh where I am so okay. So
I promised at the beginning of the episode that I
would answer if Ofio cordyceps could jump to humans and
manipulate us, Daniel. So now I'm going to ask you
what is your favorite representation of a fungus that jumps
to humans and the ant. You could just say I

(45:57):
don't watch the same shows as 'di Kelly.

Speaker 2 (46:00):
I'm not a fan of the zombie genre in general,
the violence and the goo and like not a fan.

Speaker 1 (46:06):
So yeah, I'm gonna have to leave it to you,
all right, Well, okay, I've been really liking The Last
of Us lately, but not necessarily because it like hues
so closely to what happens in nature, so that one
starts by saying, like, yes, I know it seems unlikely
that I think they call it cort aceps. The genus
name has changed a little bit, but anyway, yes, it

(46:27):
seems unlikely that it could jump to humans, but the
way our environment is changing, we can't rule it out
or something like that. And then fast forward decades and
humans are infected by the fungus. I think it is
highly unlikely.

Speaker 2 (46:39):
Why is that?

Speaker 1 (46:40):
Well, okay, so even in nature we talked about at
the beginning of the show that each opio cort Aceps
species tends to infect and manipulate specific ant species, so
they are so specialized that they can't even like manipulate
closely related ants. Like that's too much of a jump.

Speaker 2 (46:58):
So maybe like, if you you know how to fly
a Sessana. That doesn't mean that if somebody drops you
into like a seven forty seven, you're going to know
how to land that thing.

Speaker 1 (47:07):
Yes, exactly right, And human brains are so incredibly different
than ant brains. I suppose it's possible that a fungus
might be able to eke out an existence in us,
but I even think that would be quite a jump.
But if it could, the probability that it would be
able to control our behavior in a way that would
benefit the fungus seems pretty close to zero. And I'm

(47:28):
not being negative about the movies and TV shows and
books that are great and Daniel's missing out. I think
it's great that they created these worlds, and if they're
consistent with their rules, I'm on board. But I'm a
person with massive anxiety and it doesn't keep me up
at night worrying that ofiocordyceps is going to jump to
me or my kids.

Speaker 2 (47:47):
Well, I have a theory for how this fungus can
jump to humans and benefit itself. Okay, if you think
of this fungus as little neuroscientists, then what you to
do It should get humans to help it out. So
if it infects human brains and makes those humans interested
in this and puzzle. So they come along basically acting
like colleagues and figuring out like, hey, how does this

(48:08):
actually work? And maybe you can help, like you know,
super engineer this fungus to be even more efficient.

Speaker 1 (48:14):
I feel like you're in a roundabout way trying to
get back to the like it's okay that I eat
cookies at night thing, like you know, if the if
the fungus benefits from me eating cookies. But you know
what is interesting, So ofio cord accepts Senensis infects I
think it's caterpillars, but it infects craters, but instead of
having them climb up, it has them burrow into the

(48:35):
ground and then the fungal stalk grows out of the
ground and like pops up. Okay, and humans have decided
that this is amazing in tea, and so people will
actually go out in search of this and they can
sell it for a lot of money. And I think
you can even buy this in the United States, like
tea with ofio cord accepts senensus in it, and so

(48:55):
you know, I don't maybe ofio cordceps senensus jumps to
us and makes us want the tea, and so then
we'll start big farms where we sort of seed their
hosts with the fungus so that they can start growing
up and then we can replicate it. So maybe that'll
be the route.

Speaker 2 (49:11):
Or maybe that'll just be the story in your Netflix show.
Netflix call us We're ready.

Speaker 1 (49:17):
Yeah, you know, I wrote fiction once and I kind
of think it was a disaster. So I don't see
me starting a new fictional series. But if anybody would
like scientific input on their own series, I am available.

Speaker 2 (49:34):
And she promises not to be completely a wet blanket.

Speaker 1 (49:37):
I you know, I don't like to make promises I
can't keep. I'll try to play along, all right, So,
just to sort of reiterate, I love this system because
we've dug into more of the different pieces in this
system than a bunch of other systems. But there's so
much we have left to learn. And as we mentioned earlier,
like we're discovering molecules that we've never seen before. This

(49:59):
might be a way to help us understand how brains
work and how we can sort of tinker with behavior.
It might give us some inputs on how to control
insect populations. There's so much cool stuff we might have
left to learn as we continue digging into the system.

Speaker 2 (50:12):
Amazing and it's incredible what we can learn from like
ants and fungus, and sometimes that tells us something deeper
about the way brains work. And so you never know
where the next great scientific discovery will come from and
who's really pulling your strings?

Speaker 1 (50:27):
That's right, But the next great scientific discovery is probably
coming from biology. That's what I think.

Speaker 2 (50:33):
As long as it gets into people's heads and makes
them listen to the podcast, I'm all for it.

Speaker 1 (50:37):
Or it gives Daniel an excuse for eating cookies in
the middle of the night.

Speaker 2 (50:42):
Chomp, chomp, chomp.

Speaker 1 (50:51):
Daniel and Kelly's Extraordinary Universe is produced by iHeartRadio. We
would love to hear from you.

Speaker 2 (50:56):
We really would. We want to know what questions you
have about this Extraordinary Universe.

Speaker 1 (51:02):
You want to know your thoughts on recent shows, suggestions
for future shows. If you contact us, we will get
back to you.

Speaker 2 (51:09):
We really mean it. We answer every message. Email us
at Questions at Danielandkelly.

Speaker 1 (51:15):
Dot org, or you can find us on social media.
We have accounts on x, Instagram, Blue Sky and on
all of those platforms. You can find us at D
and K universe.

Speaker 2 (51:25):
Don't be shy, write to us.