How Sloths Work

Everyone knows sloths are super slow, but do you know they’re slow because their bodies produce an astoundingly small amount of energy? And did you know that might be an adaptation that protects them from predators? Sloths are awesome and we prove it.

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Episode Transcript

Speaker 1 (00:00):
Attention world. If you can make it to America, then
come see us. We are going out on the road
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going to start the whole thing off in Chicago on July,
that's right. And if you can't make it to America,
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Toronto in the next night and Fourth Music Hall. Then

(00:22):
in August, we're gonna do a couple of dates at
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be heading down to Florida. We're gonna be at Plaza
Live on October nine, and then the next night we're
going to be in New Orleans at the Civic Theater.
That's right, and then we're gonna round it out in
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(00:45):
You can get tickets and info at s Y s
K live dot com. Welcome to Stuff You Should Know,
a production of I Heart Radios How Stuff Works? Hey,
and welcome to the podcast. I'm Josh Clark, There's Charles W.
Chuck Bryant, There's guest producer Josh t over there thinking

(01:10):
about the number twenty three, just sitting there thinking about
until that's right, I forgot that. Yeah, he's in Illuminati
stuff if I remember correctly. So he's also look look
at this guy. He is so good, Chuck. He knows
to just sit there and keep quiet, even though he's
dying inside right now to talk about the number twenty three.

(01:30):
Uh if I had just pulled out some random show
from like our archive from years ago, could you see
who the producer was? Oh? I don't know, let's let's
give it a try. Um geez, Now I have to
think of a show that we did years ago. Uh. Well,
since we're doing an animal show today, the only I
can think of his animals elephants, Jarny that long ago,

(01:53):
probably Jerry All, how about this? Can you name any
shows that other guest producers were on? I'll the top
of your head. Um, No, this game turns so lame
so fast. I feel like we can we Well, Matt
Frederick's too busy these days. But we can't have Matt
anymore in here, because all Matt would do is sit

(02:14):
there and like not his head like huh yeah, yeah,
either that or his hands would be clasped together with
this look of sheer joy on his face just to
hear us talk. It was great, It made it. It It
made recording that much better. In the old days, Matt's
older and more cynical. Now he doesn't care anymore about us. Right,
He's true released into the forest like a baby sloth, right,

(02:38):
which is good. That's what you want to do with
either Matt Frederick or a baby sloth. You don't want
to keep them in captivity because sloths don't do very
well in captivity. Matt does okay in captivity, he's fine,
but a sloth not nearly as well as what Matt
Frederick can do it captivity. Uh. Yeah, and you were
watching just before we recorded. Everyone should know Josh was
watching the twenty eight million view YouTube video of Kristen Bell. Uh.

(03:04):
Can we call her friend of the show? Sure? I
mean she's probably not going to write in to object
to it, so yeah, we could. We could call her that.
She's the stuff you should know listener or has been
over the years as us. Her husband Mr Dak Shepherd,
who was also a movie Crush guest um and he
has his own podcast to Armchair expert. Yeah, he's crushing
it right out of the games. Those are good. Good podcasts, actually,

(03:27):
don't know if you listen to this are good. So
she very famously he brought her a sloth on her
birthday and she went on Ellen and they showed video
and it's still just one of the great videos you
can ever watch. It is. It's very sweet. She's like
having a meltdown and fully fully melting down. Yeah, like crying,

(03:48):
like sobbing because she's so excited that there's a sloth
in her house, because this is something she's she's wanted
to meet a sloth like for her whole life and
now she gets to. Yeah. And I watched it again
today too, because after doing this research, I was like,
wait a minute, was she holding a sloth because that's
not good? And uh, it showed a picture and she's not.

(04:09):
The sloth is on its little perch and she's very
respectfully next to the sloth, exactly how it should be.
If there's any reason that that kept Kristen Bell from
being America's Sweetheart, which I can't think of one that
that erased it right there, just knowing how to be
around a sloth when you have meltdowns at the idea

(04:31):
of being around a slot that's that's some serious self
control and for the benefit of the animal, that's great stuff. Yeah,
not touching the animal and uh literally offering for me
to change my daughter's diaper in her restaurant booth. Yeah,
that's right, because she said the bathroom was dirty. She's
a class act. Class act. So, Charles, you mentioned um elephants.

(04:55):
We did an elephant episode and that that it's similar
to the to the whole sloth thing. Like you see
a sloth, especially if you see a sloth in captivity
at a zoo or something like that, you're like, well,
I want to carry it around like a baby or
something like that. It's a sloth. It's one of the
cutest things on the planet. But you don't want to
do that. Slous don't really deal with captivity very well.

(05:16):
Although they can live way longer in captivity, they're not
necessarily happy. But I was thinking one of the things,
one of the reasons why people seem to think that
they are happy or would want to be picked up
is because, at least among one type of sloth, they're
always smiling. They're smiling, which makes them super cute. They
also have a mullet. That's the the three toad Brady

(05:39):
Puss sloth Um. They have a mullet and they are
always smiling. But if you look, it's just the coloring
on their face that happens to resemble a smile there there.
They have so little muscle mass that they don't have
the capability of smiling making their face smile. It's just
the colorings on their fur. Yeah, which is can be
very misleading to us dumb humans because they can be

(06:02):
scared or stressed out of their mind and it still
looks like they are just chilling and smiling. Right, Look
it smiling. It loves it when I juggle it with
two bowling balls in a flaming a flaming pitch fork. Oh,
I could come up with. I wondering where that was going.
Have you ever seen a flaming pitchfork? Is something only

(06:22):
in the Simpsons. So let's get into this because the
cuteness is just it's cute overload. When it comes to slows,
they are ridiculously cute. Um. Their whole vibe is just
you know, right up my alley at least sure not
that I'm lazy mellow and but well, you know me,

(06:46):
the real me isn't super mellow, but I like to
pretend to be sure, I strive to be You get
the sloth vibe. Yeah, it's it's an aspirational state, sloth nous. Yeah.
So I love. The very first sentence of this research
says they are highly successful, which kind of cracked me
up when I read it because I pictured slaws of
course in business suits, like running a company. Right, can

(07:09):
you hurry it up? I have no time for this.
But what that means is is that for a very
very very long time, slows generally have flourished in the world. Yeah,
they think that they probably evolved. Um. They're part of
a group or a family or some taxonomic designation called

(07:30):
um zenn athara and zenithara um are It's it's like
the weirdo group that's sloths and eaters. Um. I think
that's ardillos Sure, depending on whether you want to be
classy or not or sound tough. Sure, zen arthrow Okay,
I'll go with that. But it's sloths and eaters armadillos um.

(07:56):
Pretty much any odd um animal you can think of
would would fall into zan arthur what what what did
you say, zan Arthur Arthur. So they all kind of
formed together in isolation on what was once an island
South Americas as long back as eighty million years ago.

(08:17):
What yeh is an island? Yeah, you know, like the
whole continental drifts and all that stuff, and it decided
to make friends with Central America. Yeah, and and higher
sea levels that kind of thing. When the sea levels
got locked up in ice, or when a lot of
seawater got locked up in ice, the land bridge that
is Central America came along and said, hey, build some

(08:39):
zigarattes on me. So they are highly successful. Uh, they
are very slow moving, like everyone knows. Um, they are
in Central and South America. Still no surprise there. Um.
And like you said, there are two kinds there. The
two toad, uh caleppus. I was going coleo Opus colo

(09:03):
opus colo opus rhymes bosephus. Okay, that's a good way
to remember it. Uh. And then the little tom Brady Puss,
which is the three toad. But it's a bit of
a misnomer because the two toad has three toes but
two fingers, right. That's how they're classified or separated from
one another. The two toad or the three toad right,

(09:25):
so um, And technically I read somewhere Chuck that they
actually don't have legs. There's a four armed creature. Was
that the designation four arms? Yeah, from what I saw,
But they really just pay attention to how many fingers
are on the four arms or the four limbs what
we would think of as their arms, their front arms,

(09:45):
but they're really all four arms. And the way that
I kept um the two separated, so two toed is
colo opus, three toad is Bradypuss, is that I thought
the Brady bunch has more kids, so that Brady has
more toes. And it's been working all day. Frankly, that's

(10:06):
pretty good. That's the second pneumonic device you've dropped in
the first like ten minutes of the show. Yeah, what
do you think You're doing? Great? Good as long as
it's working. So uh. The two toad guys and ladies,
they roam um as far as laws go, a pretty
great distance. Uh. They can forage and ranges up to

(10:27):
three d and fifty acres, whereas the three toad guys
they only have a range of about thirteen acres. And
then there's the cutest of all sloth, the pygmy sloth
that are just on one one little island off the
coast of Panama, right, and they're actually critically endangered as
far as they are so cute, it's ridiculous. But like,

(10:49):
as close as the sloths are, like, there's not that
many differences besides the number of toes on their four limbs.
Um that the fact that you know one has the
smile mark King's the three toad as the smile markings
and the mullet haircut. The other one looks like. Um,
there's a site called Slothville. It's a it's a conservation
site run by a woman named Lucy Cook and um,

(11:12):
she says that the two toad slaws look a bit
like a cross between a Wookie and a pig. And
I think she absolutely nailed it with that description, right, Yeah,
what does them look like? The little What was the
Christmas Special? What was Chewbacca's son? Oh man, if you
can remember that, Chuck, I'll buy you a case of
beer my head, put your phone down. I don't know,

(11:32):
I can't remember, but that's sort of what it reminded
me of. Norman. I'm pretty sure it was Norman. Norman,
Norman Baca you right, I can't remember. I can't either.
I'm sure there's somebody out there. It's like you beer Josh,
I only said that I was making that offer to Chuck,
so Wookie to pig. That's a pretty good descriptor, right.

(11:55):
So my point is this, though um as as similar
as two toe sloss and three toad sloths seem, and
there are some differences, but really in the grand scheme
of things, there they seem a lot, a lot closer
than say, you know, a a dove and a sloth
flaming pitchfork in a slow um. But they're actually really separate.

(12:19):
They're not even they're multiple different species. They're not even
in the same genus. And for comparison, humans and chimps
are in the same genus. Two different types of sloths
aren't even in the same genus, so there's a big
distinction between the two and um. I looked up sloth News,
which is fast breaking strangely enough, but they they there's

(12:41):
a study that came out recently where they did some
molecular DNA studies on sloth um sloth evolution, and they
found that they may the two toad and the three
toad slots maybe even further separated and may have evolved
independently of one another, that they may be even more
distantly related than we than you think. So as similar
as they seem to be, they're actually pretty different. Although

(13:05):
they are really similar. It's a it's a weird fluke
of evolution all around. Yeah, Characteristically, I think they're fairly similar. Um,
the two toed variety are a little bit bigger, uh
and hang upside down a little bit more than the
three toed variety. Who you'll see those sitting upright sometimes
in trees. But I read somewhere that they slaus can
spend up the nine of their life upside down, yea,

(13:27):
which is amazing. They do everything upside down, They mate
upside down, they give birth upside down, they do almost
everything that they do upside down hanging and and did
you say, was the two toad that spend more of
their life upside down than the three to two toad?
A little bit more hang time, right, So that's one difference.
But even still, it's not like the three toad or

(13:48):
just averse to being upside down. I think both of
them spend so much time upside down that the part
of their hair rather than being on their backs or
their head the top of their head like ours is um,
it's on their bellies because their upside down so much
that that's how gravity is has forced their to part
just like shimp, Just like an upside down shimp. Boy

(14:08):
ships hair. Wow, it was something, it was something the
original butt cut. Yeah it was, wasn't it? Yea. So
the Brady puss also has an extra neck vertebrae. So
if you've ever seen a sloth uh seemingly turn its
head three hundred and sixty degrees, it's because they can
turn their head about two d seventy degrees and have

(14:30):
almost a three hundred sixty degree you know, counting their
peripheral vision range of sight. Yes, yes, but without that
is that is strictly from moving their head. They actually
again they lack so much muscle mass and tissue that
they don't have the muscles to move their eyeballs in
their in their heads, so when they look around, they

(14:53):
have to move their whole head. But it has helped
out for sure, especially after a hard night on other day.
But they they they the fact that they have that
extra vertebrae helps them look around more. But it's just
one more thing that makes them an extraordinarily unusual creature
because only sloths and manatees are are mammals that have

(15:16):
more than seven vertebrae. Every other mammal on the planet
has seven vertebrae, and sloss the manatees are the only
two that don't. Manatees a mammal. Yeah right, yeah, they
breathe there. They just spend a lot of time in water.
They were probably some sort of like wolf for bear
or something that eventually took to water. Well, speaking of
bears and water, uh, Slaus are really good swimmers. Um.

(15:39):
If you look up a YouTube video of slow swimming,
it's actually they can kind of get around, um and
are somewhat graceful in the water. They can hold their
breath for up to forty minutes, and in order to
do so, they can cut their heart rate by two
thirds and their metabolism down, which is like they already
I mean, we'll get into their metabolism later, but that's

(16:00):
saying something. If they can cut their metabolism down even
more on purpose, yeah for real, because the the sloth
metabolism is a thing to to behold in your mind.
It's like, um, yeah, we'll get to it in a
little bit, but just just know that I'm excited to
talk about sloth metabolism, okay. Uh. And then I mentioned

(16:20):
speaking of bears. Uh. They their original predecessor back in
the day was something called a giant ground sloth or
a megatherium. And if you look at this thing, it
looks sort of like a bear. Um its face is
a little bit different, but it kind of looks like
a just a big giant brown bear. It looked like
a giant beaver to me without the tail. I really

(16:44):
that's I mean, that's what I thought. Well, beaver with
out of tail is really just a tiny bear with
big teeth. I guess so, I guess so. But they
found that just from examining its bones, they found that
it could walk on um its back legs, which makes
it the largest bipedal land mammal that ever lived, which
is pretty cool. And there was a sloth ancestor amazing,

(17:06):
and we used to eat him to chuck. We found
um tool marks on some of the bones, and they think, well,
humans probably hunted it to extinction. Yeah, tuk took, I
guess yeah. Although we've determined he was in the anderth
all right, right, he's been designated officially as a neandertal. Uh,
shall we take a break. I think it's high time. Man.

(17:27):
All right, this is our slowest episode ever and we'll
be right back. So before we get going on more

(18:01):
real sloth stuff, I'm assuming you have not seen the
movie Zootopia or have you. I don't think kids movie, No, no,
I haven't. There's a there's a sloth scene where that's
very very funny, and in fact, they made that a
very big part of the original movie trailer where these
uh animals are in a hurry to find out some

(18:24):
information from the d m V. And so they go
to the d m V. And of course, as you know,
sort of an in joke to anyone has ever been
at the d m V, which is notably slow, they
had a sloth that was it was completely run by sloths,
and there's just this one great scene where they go
up and try to get information from the sloth and
they really do it right, they take their time, and uh,

(18:45):
it's funny for kids and adults are like highly recommend
it is, and I mean like it's probably fairly accurate
because sloths, you know, everybody knows they're super super slow.
It's not it's not really in overstatement or exaggeration. They
genuinely are extremely slow. I saw that they move on

(19:06):
the ground, which is when they move about the fastest
aside from swimming, is something like half a kilometer per
hour at top speed. And that they'll they'll move maybe
six to eight feet up a tree in a minute.
And these things are are made to climb trees. And
that's how fast, or I should say that's how slow

(19:29):
they move. Yeah, they're The actual term sloth um dates
back to the twelfth century in Spain, or in the
Spanish language at least, they were called los petasosos, which
translates to the lazies, which is hysterical because Emily and
I often call animals lazies. Look at those lazies because

(19:51):
pets are lazy. Sure, yeah, they're not sloth lazy though, no,
they're not sloth lazy. But that literally translates into the lazies.
And then when the Spanish explorers started talking about the lazies,
it was translated into the word sloth in English and
about the I guess early seventeenth century, yeah, yeah, because
it was it was a cleric I believe. Who was like, oh, well,

(20:13):
we don't talk about laziness. We talked about sloth because
it's a one of the seven deadly sins. Now, it's
really kind of a down word when it's used as
a as an insult, for sure, you know, but it's
like the slaughter of the best. So I don't know.
I like it, I know, But at the same time,
it's like if somebody calls you slothful, you know that

(20:34):
they walked right past lazy, like they saw it and said, no,
lazy is not enough. I really want to drive home
how much I disdain your laziness. Yeah, that that is
a good descriptor. Like if someone at work as slow
as something and you describe them as slothful instead of
just slow, right, because you're you're passing judgment on them
as well, like like biblical style judgment, like you're going

(20:55):
to hell, that's how slow you you took and getting
this TPS report to me. Uh two toad sloths are omnivorous,
so they can eat animals. Um. I didn't see where
they do that a lot. They mainly still eat fruits
and leaves and twigs and things, um, But they will
eat birds sometimes in lizards, I would imagine they have

(21:18):
to be wounded or something, because it's not like they
I mean, surely they don't hunt. They're not fast enough, right,
they're Yeah, they're not snatching a bird out of the
air or something like that. They're not going after humming birds.
It would have to be like maybe a recently killed
or a an injured bird. And man, if you're an
injured bird in the tropical rainforests of Central and South America,

(21:40):
I'm guessing the last thing you want to see is
a hungry to toad sloth slowly coming at you, because
you know it's going to take a really long time
for it to eat you alive. There's a funny YouTube
video actually called when a Sloth Chases You. It's just
just a sloth on the ground, like set to horror music.

(22:04):
So I watched a lot of sloth videos. There's well,
there's a lot of good ones out there. I I
recommend looking up sloth fight. Do you think it'd be
sad or disturbing? But there's a bunch of different videos
and it's actually it's in the grand sloth style. It's
really cute. When sloth's fight, Yeah, fight, fight, fight like

(22:26):
they they look like they're taking it seriously and they're
all agitated. But it's impossible for us to take the
sloth fight seriously. It's just too cute and they're just
too incompetent at fighting. Oh dear, the three toad guys,
they are very much more picky eaters, and they eat
um generally. They these toxic leaves from just a few trees,

(22:49):
and they they hang around, like if they find a
good tree that they like, they will hang around that
tree for a long long time. Yeah, there's apparently they
know that some three toad sloths will inhabit the same
tree for their whole life. It's it's rare, it's unusual,
but even still, I mean, their entire range usually doesn't
extend over like thirteen acres or five and a half hectares, right, Like,

(23:12):
it's a very small limited area that a sloth, a
three toad sloth in particular, what will inhabit their whole life. Right,
I think we can talk about the metabolism now since
we're eating. Yes, I'm so happy, so I know what
the I know what you're effect of the show probably
has to just go ahead. There's like eight in here,
So the reason slots move so slowly is because in part,

(23:37):
they metabolize so slowly. Like when you when you metabolize,
you're converting like food into energy, right, and you're doing
all sorts of stuff with that. You're moving your muscles,
you're you're walking, you're laughing, you're talking, you're recording a podcast,
you're digesting food. And slots are mammals, so they do
have this metabolism that's similar to um any other mammal metasism, metabolism,

(24:03):
it's just way slower and therefore it's way weaker. Like
the human metabolism puts out about eighty watts of energy
at any given time, Sloths put out less than four watts.
It's just extraordinarily slow, and even compared to humans are
compared to other animals there same size, they they metabolize

(24:25):
things way more slowly. So the reason that they move
so slowly is because they literally don't have the energy
to move much faster. Yeah, it's uh, it takes a
whole month to digest a meal. Um, they have to
do it. That's slow. If they would digest faster, it
could poison themselves because they're eating these toxic leaves they

(24:47):
don't have incisors, so they they trim these leaves down.
They smack their little lips together and trim these leaves down. Uh.
And again, I hate to say the word cute again,
but it's pretty adorable to see a little sloth chewing
on a leaf. Yeah. But imagine you're a wounded bird
and a toothless sloth is eating you to death. Yeah,
I imagine it's not a quick a quick death. No,

(25:10):
you get gummed to death. Uh. And I think the
fact of the show probably is this whole um, the
whole farting business. Sure, we'll take it all right. Well,
here's the deal. They eat so slow that they don't
even have gas that builds up in their system. Uh.
That is how slow they they are digesting their food,

(25:31):
so the gas just gets reabsorbed through the intestines and
into the bloodstream. Uh. And it says here that they're
the gases then, uh, respired out of the lungs. Does
that mean that they mouth for it or does it? Yeah?
I mean that's what I saw is that they have. Yeah,
they basically pass those same gases that they normally would
out of their their fannie in the American sense, um

(25:56):
the out of their mouth through breathing. Interesting. So yeah,
I guess the mouth fart worst band name ever. Worse
than diarrhea Planet. You're right, man, it's better than No,
it's actually worse than frozen poop knife. They should do
a joint tour. Yeah, yeah, you know that mouth fart

(26:17):
is going to be the opener always. They're never make
it to the headline. Boys are never headline, you know.
And I say boys because there's no way a girl
band would be called mouth fart the so uh. They
also have a multi chambered stomach sort of like a
cow um, which is really interesting because that's like a
third of their body weight if their stomachs are full.

(26:40):
Yeah yeah, and I mean, like the reason why it's
so so much of their body ways because they digest
foods so slowly, they have to have this multi chambered
stomach to get as many nutrients as they possibly can
out of it. And even still, like, it's a really
terrible evolutionary strategy to evolve as a a strictly um

(27:03):
is it or bore vous as strictly tree dwelling herbivore,
Like that's that's a really bad strategy because you have
to be small enough to exist in the tree, right, Um,
but at the same time, you have to be big
enough to eat tons of leaves every day. Well, the
if not, you're because the leaves don't give you they're

(27:24):
not very energy dense, so you have to eat a
ton of them to get good energy. Well, the sloss
evolved the different strategy. They just slowed their metabolism down,
so they can be small, but they don't have to
eat that many leaves. And in fact, they can go
for days without eating. And because they digest so slowly,
they only poop about once a week. But to to

(27:45):
the central cog of this whole adaptation is having a
big stomach that can very slowly digest every possible nutrient
out of the food that they eat. Yeah, so they do.
They defecate and urinate once a week. Um, generally in
the same spot kind of at the base of the tree.
I don't think they like to wander too far because

(28:07):
when they're on the ground they are um much more
at risk than when they're up in their tree. Um. Yeah,
because they're super slow and they're you know, they're at
risk for attack for you know, whatever, any any sort
of larger mammal could come by and have a sloth
lunch at any time, right, right, In particular, the harpy
eagle is like their main predator. But also, yeah, they're

(28:28):
they're definitely vulnerable to acelots and jaguars and um, virtually
any other predator in the jungle because they move so
slowly and they have such an inability to defend themselves.
But what they've what that Some researchers think that the
reason sloths evolved to move so slowly is because it's

(28:50):
a defense mechanism for them that rather than um like
the howler monkeys that they share the jungle with. You know,
when something comes along um and and gets the howler
monkeys agitated, the howler monkeys scream and run around and
try to escape. Sloths, right, the sloths, who may be
in the same tree as a howler monkey, um just
stays motionless and silent, and so they camouflage in with

(29:14):
the tree. So that really slow movement is actually a
defensive adaptation as well. Yeah, I think the sloths uh
defensive motto is nothing to see here. You're just like,
we're just gonna be really still. Let these monkeys take
all the attention and no one will notice this, and
that's kind of the idea. Yeah, that's exactly the idea,

(29:34):
and it works, It actually does work, and it's it's
a it's misleading, I think to say, which means I
accidentally misleat everybody that's that slows have no um recourse
if they are found out. I saw at least one
video where a harpie eagle found a sloth in a
tree and lands right next to it, and the sloth
just slowly like lifts its arm up and kind of

(29:57):
swats behind it with its claw. Man the herpie eagle
and the heartpie eagle look kind of puzzled, but it worked,
like the herpy eagle left it alone. So yeah, they
can ward off danger, just not that frequently actually. Yeah.
And you know they despite the fact that they moved
super slow, they uh, and they are lazy. They don't

(30:19):
actually sleep as much as you would think. Um, in captivity,
they will sleep a lot longer because they have, you know,
no predators around, no jaguars, and they understand that and
they're like, all right, everything's cool. I can really dig
in and sleep some. But out in the wild they sleep, um,
you know a little under ten hours, which is I
guess if you would have asked me beforehand, I would
I would have guessed, you know, fifteen and up first sloth.

(30:42):
For sloth sleep well, they will. In captivity they sleep
as much as fifteen to twenty hours a day, but
in the wild they think. Like you said, you know,
they got to be on point. And they're not stinky either,
which is another great thing, even though you definitely don't
want to slot as a pet um for reasons we'll
talk about later. They don't smell. They smell um. They

(31:02):
smell kind of like the trees they live in, which
is kind of great and another defense mechanism. Yeah. So
the reason that they smell like the trees that they
live in is because sloths move so slowly that algae
grows on them and their coats in their fur, which
other sort of amazing part. Like I had no idea. No,
I didn't either, and I don't think researchers had much

(31:24):
of an idea about this until recently. They knew that
sloths got covered with with green algae, especially during the
rainy season. Normally they have like a tan or a
brown colored coat, but when it gets rainy in the
tropical rainforest they live in. Uh, an algae like growth
will build up on their coat, which I mean, you
try to grow some algae on you, you can't do it.

(31:45):
Even if you didn't take a shower, you you move
around too much, You couldn't get any algae to grow
on you. Sloths can. And at first they thought, ha ha,
that's that's hilarious. You had another funny fact about how
slow sloths are. But as they've um, as they've researched
more deeply into it, they found that actually the sloth
coat is an amazing ecosystem in itself on the sloth,

(32:10):
and that whether it's it's it's intentional or not, the
sloth actually kind of cultivates a farm inside of its
own coat that it uses to help feed itself to. Yeah. So,
I mean I had seen pictures of these green tinted
sloths and always kind of wonder what the deal was. Um,
it helps act as camouflage, which is super helpful. And

(32:32):
I don't know, did you mention the groove in the
center of the hairs, no, Yeah, So each hair has
a little groove down the center and that's where the
algae is allowed to grow and obviously because they're not
moving fast, you're gonna get you know, more of a
chance to grow too. But like you said, they are
a little ecosystem into themselves in that fur. Uh. They
did one study that found nine hundred and eighty beatles

(32:54):
living on a single sloth just taking roosts in there
and their little jungle coats. Uh. And then there's this
moth species. This is crazy um, the sloth moth, which
is another great band name by the way, cryptosis. Uh,
calepi colo epi color epi. Always say just the e

(33:17):
it's always ohe I think you're right, yeah, color epi coloiepi,
colo eppie, something like that, tomato tomato, cryptosis colo weepie
dyer uh. And they they actually colonize exclusively in sloth fur. Right,
that's the only place you will find that type of

(33:37):
moth is living in the fur of a sloth. It's
the sloth moth. Yeah, like totally symbiotic relationship. Uh. You know,
they climbed down the once a week to poop and
they they these moths lay their eggs in that poop. Um.
And yes, they can actually lay their eggs in dingle berries,
sloth berries. Everyone knows what that is, right, do we

(33:59):
need to explain that. I don't know. I would say
look it up. Okay, I think that's as far as
we need to say. So the adult moths emerge from
this poop, uh, and that they then say mama, and
they fly up and take rest in the slots fur, right,

(34:20):
and then they mate and reproduce, and then they lay
eggs in the sloth poop and the circle of life continues.
But again, this type of moth you won't find anywhere
on Earth except in the fur of a sloth. And
then there's also beatles in there. And so as these
things like grow and die and decay and other plant

(34:41):
matter and whatever is floating around in the air in
the rainforest all kind of combined and get stuck into
these grooves and the hair of the sloth fur, it
forms this algae. And they know that there is um
a relationship between the sloth moth and the algae in
that the sloughs that have the most moths also have
the most algae. And they figured out it's just basically

(35:04):
this decaying matter and they're like, okay, this is too weird.
Camouflage that kind of makes sense. But the fact that
there's a moth that only lives in in the sloth fur,
and the more more of those moths are, the more
algae there's it's just too weird, and um, they tested
this algae and they found that it's rich in fats,

(35:25):
and for a very long time they're like, Okay, the
metabolism kind of explains how a sloth could sustain itself.
It's just it burns so little energy that it it
it can live on very very nutrient sparse leaves. But
it's still kind of a mystery. It doesn't fully make sense.
And they think they figured out that the sloth as

(35:46):
it's grooming itself eats this algae which is high in fats,
and that that supplements its diet of leaves, and that
that's really the combination of these leaves and this algae
are what keeps the sloth live over its lifetime. And
in the meantime there urine and their feces are fertilizing

(36:07):
the tree that is their habitat, right where these moths
are also laying their eggs. So it's just like this
really unique symbiosis going on between plant, animal, and insect. Yeah,
and everyone seems to be doing great. Yeah, And one
of the thing I was like, well, you know, how
much does that really help? The sloth is pooping at
the base of the tree once a week. Does that

(36:29):
really help? And apparently it really does. And it's not
one of those It is slow, really, so you just
nailed it. So sloths are so slow their poop actually
slows down the decomposition in the tree because in the rainforest,
decomposition happens so fast that the tree as actually nutrient depleted.
Because the decomp happens so fast, sloth poop slows the

(36:51):
whole process down and actually nurtures the tree even more. Yeah,
it seems like everywhere the sloth goes, everyone just chills
out it. Basically, the sloth dingleberries are just little rainbows
trailing out of its behind. That's what sloths have. You
have to look closely, but you'll see it. It sounds
like a story my daughter would make up. So you

(37:12):
do share a birthday, hey, which is coming up actually
probably right around the time this is released. So oh yeah,
well birthday day Ruby. All right, we'll take a break
and we'll come back and talk about sloth sex right
after this. All right, Chuck, you promised it. You have

(37:53):
to deliver sloth sex blow by blow. So here's the deal.
This is where things like if you're like, all right,
the sloth is the cutest thing, and this is all adorable,
and they're just amazing, they are all those things. But
this is when you might I just want to prepare
everyone to be slightly disappointed, maybe a little bit with
the next couple of segments, because first of all, sloths,

(38:17):
you want to just think they sit around and just
hug in love on each other all the time. They're
solitary creatures. They don't want to be around even other sloths. No,
but but this is something that you can have to
kind of pick yourself back up after that devastating blow
in in a square kilometer of rainforest, there might be
something like seven hundred sloths even though there, yes, they're

(38:42):
they're very dense neighborhoods of basically shut in weirdos. Imagine
that that's a sloth community. The most devastating thing is
coming up later. I know you know what I'm talking about.
Oh yes, boy. But the males, like let's say, to
sloths did find themselves in the same tree, they might
get into a little fight but more than likely they'll just,

(39:04):
you know, one of them will leave and they'll go
find their own tree and it might be a tree
ten or fifteen feet away, it sounds like, but it's
their own. Um. They look for new trees. Also, when
they're searching for a female partner, the males do and
they mate very quickly. It's um. It lasts just a
few seconds and then the males leave the female. They

(39:24):
don't have anything to do with the babies, which I
looked up and I was like, surely they have some
cute name like sloth babies, but they're just called sloth babies,
which is cute. Yeah, that's pretty cute. Not bad. So
you know, you know, we were talking about fertilizing trees
and everything. When they come down and poop once a week,
I know where this is headed. So that was a
big That was a big mystery, Like why would you

(39:46):
if you're a sloth, coming down from a tree to
poop uses up about eight percent of your energy. That's
a lot, and it doesn't make any sense because it
leaves you vulnerable to predation. Some researchers say, we gotta
figured out they're leaving scent markers on the tree to
signal to other sloths come on over here. Um, I'm

(40:08):
I'm open to to whatever freaky stuff you want to try.
Sloth friend, Yeah, anal secretions, so he, like a male sloth,
will literally just say I'm just gonna rub my ans
here and I'll meet you back there at eleven o'clock
at least a little rainbow trail. I guess. So the
female can also and and I heard these. Uh. I

(40:28):
looked up some videos on the female mate mating call
or whatever, because they can also put out the call
that they're ready. Um. And it's described as a high
pitched scream here in this article, but it sounds sort
of bird like, like if I was in the jungle
and I heard this, I would think it was a bird. Yeah,
it's not sexy, though, it's not sexiest animal. Did you

(40:50):
get that reference right now? No, I didn't, but I
appreciate you saying it was a reference Beverly Hills Cop Balki,
Oh yeah, yeah, yeah, it's a little cameo on Beverly
Hills Coop. He was one of the all time greats.
I never watched that TV show. I know you didn't.
And Chuck, you're missing out. Remember I keep going back
to that piano moving episode, and it was just one
of the greatest of physical comedy ever really. But yeah, also,

(41:15):
and it wasn't just Bouky, like, Balki and cousin Larry
were really well cast. They're perfect foils. Seeing cousin Larry
get like his last bit of patients just break and
his eyes get really big because Balki did something, it
was a beautiful thing to behold. Cousin Larry. Was he
the other guy, the main guy? Yeah, I see it.

(41:35):
I see a DVD box it in your future. Were
they actually cousins in the show? Yes? Not in real life.
I mean I don't know the set up at all.
Is it that he has this wacky cousin from another
land that all of a sudden shows up on his doorstep. Yeah,
Balky Bartacamas from I can't remember. They say it a
bunch of times, but his he's like a central southern,

(41:59):
central European type guy, like from the Balkans or something
like Latvia or something. And he comes over to America
and he stays with his cousin Larry. I have to
check it out. It's funny. All the all the great
TV out that's mounting on a list. I'm like, I'll
have to check out perfect strangers, right right exactly, it's
on my list should be high up. So the woman

(42:20):
puts out the maiden call the males. Uh, there may
be competition for uh for that lady um who is
in need. And if they do fight, they will fight
upside down and uh, like you said, it's um a
slow fight, is I guess pretty cute as it turns out, right, yeah,
it is cute. So yeah, the males will fight to

(42:41):
the to the hurt bruised ego, and then one of
them will leaven the mail that remains will say, okay,
give me a kiss, baby, and then they'll have um.
They'll do it like a few times. Uh, but it's
really fast. Apparently I didn't I have enough pride, did
not look up sloth sex. But um, from what I read,

(43:02):
it happens very quickly. And then that's that and like
like you said earlier, the male just kind of moves
along like good luck with our children, and then the
sloth um ges station period depends on whether it's a
two toad or a three toad sloth, but it's somewhere
between six and eleven months and then a sloth mom
will give birth to one sloth baby at the time.

(43:24):
No letters, nope, just one cute little baby. So here's
where it gets devastating. Um. They do nurse their young
for a little while, but again, that takes a lot
of energy to nurse a little baby, so they only
do that, um for a couple of weeks before they
wean that baby onto solid food. The mommy is passing
along all the information that the baby needs to know

(43:46):
about what food is and how to how to hang
and live in trees. And they do cling to their moms,
which is super cute, for about six to eleven months. Um,
and then they are off on their own. Although they
do this is sort of cute. They do share arrange
with mom and apparently we'll stay within uh calling distance

(44:07):
of one another. M And this is all great, and
I know I'm set set everyone up for heartbreak. So
here it goes. If a mommy sloth is up in
a tree and baby sloth slips and falls down to
the ground, mommy may just leave baby there. Yeah, that's
like really hard for me to accept. I know. Uh,

(44:30):
because a baby sloth is cute. Adult sloths are cute enough,
but a baby sloth is just like I bleach right,
so to to the idea of it just being like
down there on their own. It was a great three
months we had together, but I'm not going to put
myself in the at risk of being a vulnerable vulnerable

(44:51):
to to some sort of a deal, right. Yeah, that's
what they think is that the baby is just not
worth it to the sloth, which is really said. I
would understand that if there were sloth litters and one
of them fell off, or that they didn't bond, but
they clearly do bond during the piggyback phase of the
baby's development. Yea, So it's they think that it's just

(45:12):
like it's just too much of a risk for the
sloth and the law says better you than me. Kids. Yeah,
this this disturbed me because I was the same as you.
I was like, if there was a litter, I get it,
or if they like they're highly successful, so you would
think that you know, after a nine you know, up
to a year of gestation period, or if they pump

(45:34):
babies out like every month or so, it wouldn't be
a big deal. But I don't know. It just seemed
like it was worth that eight percent energy and maybe
a risk of panther uh feed being panther feed, right,
So I mean, I guess it would if that happened,
that the baby falling happened to coincide with the mom
having to poop at the base of the tree, maybe

(45:56):
the baby has a chance. Then I'm gonna save you
because I got to take a right oh man, um,
So let's just go right past that, because that is
still super sad for me to think about. They do
live for about uh twenty years in the wild, which
is pretty good for her mammal, especially when that's slow
and that you know, seemingly defenseless. Yeah, that's the three toad. Yeah,

(46:19):
the three toad. The two toads live about twelve in captivity,
though they can live thirty and forty years. Uh, including
our old friend Missy at the Adelaide Zoo in Australia,
who just died a couple of years ago at the
old age of forty three. For from what I understand,
she's the oldest um known sloth to to live. She

(46:40):
looked at the fact that she did. She looked great
up to the end, like Phillis diller Um and the
fact that uh that sloths lifespans double or triple in
captivity really kind of says a lot about just how
how much, how how frequently they fall victim to predators
like that, to what kills sloths is, it's not fighting

(47:02):
with other slaws, it's not falling from trees. They can
withstand that, it's being eaten by a predator. That's how
slaws typically die. So when you take them out of
that situation, they tend to live very long. But like
we were saying at the top of this episode, they're
not necessarily happy. They get very stressed out when humans
handle them, and they can actually die from stress. Um.

(47:25):
They look happy, but they would much rather be at
their home. In Central and South America really really really
really difficult to keep alive because remember, especially with the
three toad sloth, they're real picky eaters, and they learn
from their mothers what constitutes food, and so whatever tree
that their mom's been living in basically that specific tree

(47:48):
growing in a rainforest in in South America, that is
what constitutes food to the sloth, not anything else you
could possibly come up with, and so they'll still starve
in captivity pretty easily. Actually, especially if they're kept in
captivity outside of Central or South America. Yeah, so if
they do. Let's say you're a wildlife management professional and

(48:11):
you come upon a little baby sloth that has been dropped,
they will rescue that sloth if they can and try
and rehabilitate it, but the goal is to get it
back into the wild as soon as possible, not like,
oh it's so cute, we're gonna keep it around for
a little while. I mean, there are clearly some in captivity,
but it's not like a common zoo animal that you
will see. Right. There was one other thing that was

(48:33):
kind of a quirk of their metabolism. So their mammals,
which means they're warm blooded, but they're actually not really
warm blooded because they produce so little energy and heat
through their metabolism. They actually use the same kinds of
strategies that like snakes and lizards do, where they use
the sun to adjust their body temperature, which means that

(48:55):
if it gets too hot, they can overheat and die.
If it gets too well, they can very easily freeze
to death because their body temperature changes with the ambient temperature.
So that, combined with the fact that their food comes
from a single tree in Central America. Um. That makes
them really difficult to keep alive in captivity, which is why,

(49:15):
like you're saying, they want to rehabilitate them back into
the wild. That's the goal of it. Yeah. And while
they are doing pretty well out there as far as
their um status goes, they are of course threatened in
the sense that any animal in South America and the
rainforest is threatened because of deforestation. Uh. It's just you know,

(49:38):
the sad fact all animals, even if they're doing well,
are going to be threatened if you're hacking through and
and leveling their habitat, like is what is going on
pretty much. Yeah, that's I mean, that's the biggest threat
is deforestation. Although for the pygmy sloth that lives on
a scudo island off of the coast of Panama and

(49:58):
nowhere else be because their their habitat is so limited
that any deforestation that happens there is put them in
grave danger. Um. But it's basically cutting down the forest
and then building roads through the forest because sloths will
go from tree to tree on the ground sometimes, which
means that when they encounter a road, it's hard to

(50:19):
get from one tree to the other aside from on
the ground. So a sloth crossing the road is probably
not a good gamble for the sloth. But the more
roads we build through the rainforest, the more sloths to
get hit by cars, which is about the saddest thing
you could hit by a car with a car. Yeah.
And here's uh, you know you always hear about um

(50:40):
like a movie medicine man, like the cure for cancer
maybe in this one leaf in the middle of a
forest somewhere in a jungle. They may not have the
key to cancer in a sloth, But the Smithsonian Tropical
Research Institute did collect fungi samples, you know, the algae
that grows in their fur. Uh. And this is of
the three toed sloth. And they own that some of

(51:00):
these samples from the sloth coat helped fight against malaria
or the parasite that causes malaria and um chagas disease,
which I know we've talked about. It's another tropical parasitic disease,
stop your heart mersa cholera, salmonella. Uh. And they were
also active against human breast cancer cells. So pretty amazing, yeah,

(51:23):
which I mean, like that's the stuff that they found
in the algae growing on sloth fur, which, Yeah, that
is astounding. It's awesome. So we're all gonna be chewing
on sloths in the future. Well, yeah, don't say that.
They'll be alive. You don't have to kill him or anything.
Gently suck on their fur. Okay, okay, Um you got

(51:45):
anything else? I got nothing? Well, if you want to
know more about sloths, there's a whole internet out there
about them, although we did a pretty good job covering
at Chuck if I do say so ourselves. Um, well,
since I said Internet, that means it's time for listener man,
I'm gonna call this politics on your show. Hey, guys,

(52:09):
love the show. I've been listening for several years now,
and I've learned lots of good stuff. And you've also
introduced me to the end of the World with Josh
Clark and movie crush. Yeah how about that? All right?
Will goes deep? Uh And he says this recently, I
was looking through reviews and comments on the show on
Apple Podcasts. I saw a number of people making critical
comments about how you share your opinions on religion and

(52:30):
politics too often. Um, I am a politically conservative and
religious guy. And I want to encourage you to keep
sharing your opinions. I live in a smallish Midwestern town
and a red state where I grew up and spent
most of my life. Most of the people in my
orbit either go to church with me and my family
or hold similar conservative views. Your opinions serve as an
important function of bringing some alternate alternative perspectives that sometimes

(52:55):
challenge my opinions and encourage me to reevaluate certain positions
and views. Please keep interjecting your views, guys. Too many
of us automatically dismiss any opinions, and unfortunately people who's
views contrast with their own. UM. I used to work
for an administrator. He would frequently say, if we're all
thinking the same thing, then some of us aren't thinking

(53:15):
that sounds like something. That's a really great that's a
great solational poster. That's good. That's that's the first album's
title for Mouth Farts debut. Keep up, boy, keep up
the great work, and keep offering your views along with
your well research and fascinating topics, well seasoned with witty
humor and hilarious banter. Regards will Well, that was a great,

(53:39):
very nice, very kind email, like Will saw something probably said.
These guys probably know about this, and I want to
make sure that they know it's cool. So thanks Will
as much appreciated. Um, if you like to join in
with Will's course, we love that. I would also be
interested to hear other people who want to write in

(54:01):
and explain why we shouldn't share our politics or views,
because I'm I'm very curious to hear the other side
as well. It makes me a centrist. Fairness dot com right,
You can go to stuff you Should Know dot com
and find all of our social links there, and you
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(54:27):
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