0:00

Wendy, I have a story for you and

0:02

it is absolutely batshit and

0:05

you are gonna wanna hear it. Oh!

0:11

I have no idea what you're gonna

0:13

tell me. A lot is about to happen.

0:20

Here with me

0:22

is award-winning science journalist and

0:24

host of Every Little Thing, Flora Lichtman.

0:27

Hello, Flora. Well,

0:30

the team at Science Vs. is diving

0:32

into topics. For next season, Flora

0:34

was like, Wendy, turn on your

0:36

microphone. I gotta tell you something about bats.

0:38

This can't wait one more minute, Wendy.

0:41

I'm here, ready to go. Right

0:44

off the bat, I wanna introduce you to Emma Teeling,

0:47

bat biologist and full professor of zoology

0:49

at University College Dublin, because

0:51

she does not fly away from a bold statement on

0:53

bats. They are by far

0:56

the most magnificent of all

0:57

mammals that have the rarest of all traits.

1:00

Emma is going for it. The most magnificent.

1:02

I mean, I did feel I'm very competitive, so

1:04

I was like, whoa. Does she

1:07

know me?

1:09

Anyway, bats bring it on.

1:12

Let's just count the ways. Bats turn

1:14

teenage human heartthrobs into teenage vampire

1:16

heartthrobs. They give Sarah

1:18

Michelle Gellar seven seasons of work and

1:21

no more. I'm a vampire slayer.

1:25

They also created the

1:26

best Sesame Street character. I am the

1:28

Count because I love to count.

1:30

I really love to count.

1:33

Betty, Betty, Betty, Betty, Betty, Betty, Betty,

1:35

Betty, Betty. But beyond their IMDb

1:38

cred, bats are the only mammals to

1:40

fly.

1:41

Plus, they echolocate. They find

1:43

their way around in the dark by making sound

1:45

and listening to how it echoes. That's crazy.

1:48

But there are two special bat tributes

1:50

I want to home in on today.

1:53

First of all, they live for a

1:56

weirdly, mysteriously

1:58

long time. The longest-lived

2:00

bats can live for decades. Interesting.

2:03

And number two is about their immune system.

2:06

Many viruses that kill us, from

2:08

the flu to Ebola, bats

2:11

brush them off like a fly. So

2:14

bats scat all over aging,

2:17

and they fly in the face of immunology. And

2:19

I am going to hang upside down from a spindly

2:21

limb and say,

2:24

bats break science. Whoa.

2:28

That's a very big call, Flora. How

2:31

do they live so long and crush killer

2:33

viruses? And what can we learn from them? Wouldn't

2:36

you like to be youthful until you die?

2:38

That's what we're clawing into today.

2:40

I'm in. I'm holding on stalactitely

2:44

to your every word. Oh,

2:47

sorry. You've been getting such a bad influence

2:49

on me, Flora. Do not blame

2:51

me, Wendy. That's ridiculous.

3:01

You know your favorite

3:03

superheroes now. So Iron Man, Captain

3:05

America, Thor, Hulk. But Marvel's

3:08

path to dominating the box office wasn't

3:10

an easy one. Oh, it was a real god

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punch. We were a nothing company. He developed

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a fire in his belly of

3:17

hatred. From The Journal,

3:20

a new four-part series with great

3:22

power, the rise of superhero

3:24

cinema. Find it in The Journal

3:26

feed on Spotify or wherever you get your podcasts.

3:32

Hey there. This is Jonathan Goldstein, host

3:34

of Heavyweight, with some exciting news.

3:37

Heavyweight is now available for free wherever

3:40

you get your podcasts. What this means

3:42

is that you can listen to any episode from

3:45

any season on any podcast

3:47

platform.

3:48

This goes for the new season as well, which

3:50

starts in September and will be available

3:53

everywhere. Start polishing your

3:55

earbuds. It is going to

3:57

be a doozy.

4:04

Welcome back. Today we are

4:06

uncovering the mysteries of the

4:08

bat with Flora Lichtenbein.

4:11

Now you're going to tell us why bats live forever.

4:14

Forever. Yes.

4:17

And Vendi, this is the first thing you need to

4:19

know.

4:20

Life span for most mammals follows

4:23

a general pattern. You're born,

4:25

you suffer, and then you die, probably

4:27

alone. Oh, come now. There's

4:30

some podcasts in the middle there.

4:34

And generally for mammals, the

4:36

bigger you are, the longer you live.

4:39

And the smaller you are, the shorter you live.

4:41

Here's bat biologist Emma Tealing again.

4:44

Small things, they live very

4:46

fast, and they die young. Think

4:48

of a mouse, think of a shrimp. So

4:51

the thing is that bats are unusual

4:53

because they buck this trend. Humans

4:55

buck the trend too. Shout out to soap

4:59

and medicine. But

5:02

if we lived proportionally as long as the

5:04

longest lived bat corrected for body size,

5:06

we'd be living for centuries. We'd

5:08

be like 250 years old.

5:11

They blow us out of the cave on

5:13

life span.

5:14

And that is with all of

5:17

our medical intervention. Wow.

5:19

That is so impressive that

5:22

they bat us out of the water with

5:25

no vaccines, no hand

5:27

washing. No

5:30

hand washing. I really love

5:32

the image of them at their tiny

5:35

little sink, sudsing their little

5:37

claws. And

5:39

it's not just that they live a long time.

5:42

Researchers don't find many visible

5:44

signs of aging. For example, gray

5:47

hair. You don't see that in the bats that we're looking

5:49

at. They seem to be able to reproduce into

5:51

old age. And here's the kicker. They

5:53

don't show signs of age-related disease.

5:56

You don't seem to see evidence

5:58

of cancer. You don't

6:01

see evidence of big tumors on

6:03

these bats that are living way longer than expected. You

6:05

don't see this.

6:06

So it's not just that they're

6:08

holding on by a thread into

6:10

old age. They are literally

6:14

like vampires. I think they're

6:16

more like Paul Rudd. They age

6:18

so slowly you can barely detect it. So

6:25

under the hood biologically, what

6:27

is happening here? That is

6:29

what Emma is batting her head against

6:32

the wall to find out. There is a question

6:34

I want to know.

6:35

How do bats resist aging?

6:39

To find out, for over

6:41

a decade, Emma has been studying these wild,

6:43

long-lived bats in Brittany, France, along

6:46

with a colony of scientists, which

6:48

included Nicole Foley.

6:50

I did my PhD with Emma, who I think you've been

6:52

talking to previously. Nicole's now a

6:54

research scientist at Texas A&M, and

6:57

she was the lead author in the study we're going to talk about.

7:00

So Nicole was out studying these bats,

7:02

but the field sites are maybe not exactly

7:05

what you'd picture.

7:06

These bats are not living in caves.

7:09

There's some that are in churches, some

7:11

that are in the roofs of schools.

7:13

These scientists work with a French naturalist

7:16

association that helps them track down

7:18

these long-lived bat populations and arrange

7:20

access, including to these old

7:23

churches. And I just want Nicole to

7:25

paint you a picture.

7:26

The churches are amazing. Think of

7:29

the most kind of Dracula

7:32

Gothic

7:32

church with the really narrow

7:35

steeples, and it's super high and

7:37

imposing. Yeah, I mean, just picture

7:40

what if Disney had to do a

7:42

church for a villain? So

7:45

the bats wiggle their way

7:47

in under the shingles of the roof and

7:50

hang in the attic. How

7:52

do they catch them? This is another fun

7:54

detail. Compared to other bat

7:56

field work, in this project,

7:58

catching them is kind of a sin.

7:59

Normally you go out and you put up nets

8:02

and you stay out all night in the forest and you

8:04

catch bats that way and it's hard, really,

8:06

really hard work. Because we

8:08

knew that the bats were in the attic and we

8:11

knew where they were coming out, we

8:13

just had to make a little contraption. It's

8:15

called a harp trap because it just has

8:17

all of these straight strings hanging down from it.

8:20

They put this harp trap over the

8:22

bat exit

8:23

and then the bats fly out, they bump

8:26

into the strings. And then we just kind of had

8:28

a plastic tube waving

8:30

its way down into just a box on the bottom

8:32

and you get a box of bats. It's

8:35

like a laundry chute of bats. I mean

8:37

I kind of feel bad for the bats, right? Because

8:39

they're hanging out in the attic and they're like, time to party

8:41

for the night. And instead they're like, whoa,

8:44

now I'm in a box. So these

8:46

scientists have been catching these bats for years

8:48

and they track them over their lives. So

8:50

here's Emma again. Every single

8:53

bat that's born in this colony, we catch

8:55

them year after year after year at the same individuals.

8:58

We take a little bit of wing,

8:59

we take a little bit of blood, a few drops. And

9:02

then they analyze this tissue and blood to try

9:04

to figure out why bats live so

9:06

long. We release them

9:08

and we look at markers of age.

9:11

And one of the markers Emma has looked at are

9:13

telomeres. These are the little caps

9:15

at the end of our chromosomes that protect

9:18

your DNA from degrading, which is important

9:20

because generally speaking, DNA

9:23

damage can lead to cancer and

9:25

other problems. And so what's going on

9:27

with bats telomeres? Okay, so

9:29

generally in mammals, you may recall that

9:32

telomeres get shorter as you get older.

9:34

Right. And the science is changing all the time,

9:36

but this shortening is considered one

9:38

of the classic hallmarks of aging. That's

9:40

why Emma was looking at it.

9:42

So we asked this question, do telomeres

9:44

shorten as we would be expected in these

9:46

long-lived bats or not? And

9:49

we looked at young, middle-aged and older bats.

9:52

So they asked, do older bats have

9:54

shorter telomeres

9:56

than younger bats?

9:57

And what we find with extraordinary.

10:00

In the longest lived bats, the

10:03

tealumors did not shorten with age. Wow.

10:09

In the older bats,

10:11

their telomeres on average weren't

10:13

shorter. Yeah. This was

10:15

a big result. It was so

10:18

surprising that Nicole,

10:20

Emma's student at the time, couldn't believe

10:22

it.

10:23

This was her response. It's just

10:25

is wrong. What did I

10:28

do? I feel like that's

10:31

a natural tendency. It's like, oh, that's interesting.

10:33

It must be nonsense. Then

10:35

you go back and you do your

10:37

living best to find all of the things that you may

10:40

have done wrong. And eventually you kind

10:42

of get to the point where

10:43

you run out of ways of

10:46

confirming that you're wrong. So

10:49

you must be right.

10:53

Wait, why was she so unconvinced

10:56

and then convinced? Is that because this is so

10:58

confounding that these bats

11:00

don't have this

11:02

telomere shortening thing? They're

11:04

not following the rules. Here's

11:06

Emma again. So what this meant

11:08

was that potentially bats had a way

11:11

of maintaining telomeres, which

11:14

is a good thing, but how do they do it?

11:16

And Emma's working on it. She has a couple of leads,

11:18

some genes that might be responsible. Right.

11:21

So our telomeres,

11:23

the reason why bats have this longevity

11:26

superpower? Well, as we know from the Marvel

11:29

universe, unraveling a superpower

11:31

takes like 19 Robert

11:33

Downey Jr. movies to really unpack. So

11:36

telomeres are thought to be part of it, but the full

11:38

story is complicated. But

11:41

next up,

11:42

how bats bat away viruses that

11:44

make humans shudder in fear, which

11:48

also has a starring role in the

11:50

bat longevity story.

11:52

Coming up after the break.

12:07

Welcome to the Bat Cave. I'm here with special

12:09

guest Flora Lichtenmann. We are swooping

12:11

into the science of bats.

12:14

Next up, why bats

12:16

look at viruses the same way

12:19

that Buffy looks at vampires. Is

12:22

that what we're doing? Couldn't have put a bat on myself.

12:25

So, yeah, one of the things that bats are known

12:27

for is their ability to fight off viruses.

12:30

And I've got an expert to fly through the science with us.

12:33

Matean is a bat biologist and

12:35

human clinician from Duke and US

12:37

Medical School in Singapore.

12:39

Yeah, bats, what they are most

12:41

famous for actually, or sometimes infamous,

12:44

is carrying many, many nasty viruses.

12:47

Yes. I feel like from the pandemic, this is

12:49

one fact a lot of people picked up about bats, right?

12:52

Because there's a lot of coronaviruses in bats. Yes,

12:55

SARS, MERS, and other kinds

12:57

of viruses too, like Ebola. Bats

12:59

carry viruses that cause deadly

13:02

epidemics in humans. They get infected.

13:04

They don't show symptoms. They don't get sick. And

13:07

then they clear the virus. I'm so

13:09

jealous of someone who's had a lot

13:11

of viruses this year.

13:15

Now, anecdotally, they don't

13:17

seem to show the same invincibility when it comes

13:19

to bacteria and fungi. You might

13:21

remember white nose syndrome, the

13:23

fungal disease that's killed millions

13:25

of bats across North America. Right,

13:28

yes, yes, yes, yes. So not

13:30

fully invincible, but seemingly invincible

13:33

to viruses. Yes, most

13:35

viruses. So how do they do that?

13:38

They do it by keeping their immune system

13:40

in a Goldilocks zone.

13:43

So for mammals, there's a sweet

13:45

spot when it comes to an immune response.

13:48

You want your immune system to attack and

13:50

clear the virus, but you don't want it to

13:52

fly out of control. Too much immune

13:54

response can damage healthy cells, and

13:57

you can die from that. In COVID, the

13:59

immune response.

13:59

inflammation is often what kills people.

14:02

Right. So, bad immune

14:04

systems don't fly off the handle when a virus

14:07

invades.

14:08

How do they do that? Like, what is the...

14:12

What's the break in their immune system that

14:14

stops it going haywire for viruses?

14:17

Great question. And I'm

14:19

happy to tell you that we are alive at the

14:21

exact right moment in history to

14:24

get an answer. Mate and

14:26

colleagues just published a big paper

14:28

on this. They looked at inflammasomes.

14:31

These are, like, first responders in the immune

14:33

system. Okay. Bats have

14:35

them. We have them. Have you heard of them?

14:38

No, no. It sounds like another pun, but

14:40

it's real, this one. This one's real. And

14:42

you're not alone.

14:45

Even among clinicians, most people don't

14:47

know.

14:48

I never learned it in my medical school. You

14:50

know, I never learned it in my PhD as well.

14:52

So that's how new it is.

14:54

This is the bleeding edge of immune research.

14:56

What is an inflammasome?

14:59

So in your body, there are proteins called

15:01

inflammasome sensors that

15:04

float around and detect danger, like

15:06

viruses, bacteria, cell damage. And

15:09

when they sense a problem, they,

15:12

along with some other proteins, come

15:14

together to form an inflammasome.

15:18

Now, that inflammasome then can deal with

15:20

the problem directly.

15:22

It can also recruit other members of the

15:24

immune system to help out. Oh,

15:26

and this is different from antibodies and

15:29

other more well-known

15:29

stuff in our immune system. Like, this is

15:32

a new thing in the immune system

15:34

that we're still working out. It's

15:36

another player, and it's a major player.

15:39

Inflammasome play a very important role

15:41

in aging, including age-related diseases.

15:43

Like Alzheimer's, Parkinson's,

15:46

diabetes, heart disease, and

15:48

they're key responders to viruses.

15:51

Now, because bats don't show

15:53

signs of age-related disease, and

15:55

they fight off viruses so effectively, Matej

15:58

and his colleagues wondered...

15:59

if their inflammasomes were different

16:02

somehow. Are they different somehow?

16:04

Well, through a ton of molecular

16:06

detective work, they found that bats

16:09

make a protein that suppresses their

16:11

inflammasomes. And that's what's

16:13

keeping their immune system in this Goldilocks

16:16

zone. That was the hypothesis.

16:18

So to test it, Matei and his colleagues

16:21

genetically modified mice, so

16:23

they made this same inflammasome

16:25

suppressing protein, just like the ones

16:27

that bats make. And then they exposed

16:30

these mice to inflammation-inducing

16:32

crap of different varieties, like

16:35

the flu and chemicals

16:38

that cause irritation. And so what did they find?

16:41

So it was really cool. They found

16:43

that these modified mice reacted

16:47

more like bats.

16:48

They didn't have as much inflammation in

16:50

response to these irritants, and they

16:53

were way less likely to die from the

16:55

flu. Wow.

16:57

Wow. So can I get genetically

17:00

modified? Like, can

17:02

they give me that protein? I want that protein.

17:04

Matei wants you to have it too. They're working

17:06

on this exact thing, a human

17:09

drug version.

17:12

Amazing.

17:13

It's amazing that bats just

17:15

have collected these tools. Like,

17:19

why bats? Why are bats so

17:22

good at all this? Yes, that

17:24

is such a fascinating question.

17:26

And

17:27

it's a batter of debate.

17:29

So one theory I heard is

17:31

that it comes down to their communal lifestyle.

17:34

Some bats live in colonies of millions.

17:37

They are packed into these caves,

17:40

winged to jowl, which

17:42

is just perfect conditions

17:44

for virus transmission. So

17:47

to cope with this germstorm, their

17:49

immune system adapted, which might help

17:51

them live longer.

17:53

That's super interesting. It's just making me think that

17:56

humans, because we also live

17:58

in these incredibly dense cities. now, but

18:01

we haven't evolved that way, right? This is a very

18:03

new modern phenomena to be so

18:06

densely packed in our little

18:09

caves. Yes, exactly. We

18:11

live kind of like bats, maybe not quite as densely,

18:14

but we don't have the immune system of bats. But

18:17

here's another theory about how bats got

18:19

this fairy tale immune system and longevity.

18:22

And this one I heard from both Mate and

18:24

Emma. It's the theory I am

18:26

buying the most right now.

18:28

It comes down to flight. Okay.

18:31

So flying is hard on a bat. A bat's

18:33

heart rate can go up to a thousand beats per minute.

18:36

Think of them like tiny, furry

18:39

flying race cars. They're operating

18:41

at the extremes. They're stressing their machinery,

18:44

guzzling fuel, and spewing

18:47

out chemicals. And all that

18:49

can lead to DNA damage, inflammation,

18:51

and other problems.

18:53

So the idea would be that

18:56

to evolve flight, bats

18:59

have had to evolve a countermeasure to deal

19:02

with this. And the countermeasure is what

19:04

protects them from the damage of

19:06

living and allows them to have longer health

19:08

span. And so they needed these

19:10

adaptations or they would have just died. Like if you're

19:12

going to have flight as a mammal, you

19:15

better darn well have a proper immune system

19:18

to handle that or you are

19:20

crashing and burning. Crashing and burning.

19:22

Yeah. Mm-hmm. Is this how Superman

19:25

can survive? He's

19:27

actually a bat. I think that's Batman. I

19:32

think it's the other one. But

19:35

Batman can't actually fly. He's just

19:38

a rich guy. He's just a rich guy.

19:40

Everyone forgets that. He has no superpowers

19:42

other than money. Yeah, you're right. So

19:44

anyway, there are no peck holes in this flight

19:46

theory because birds don't have all these adaptations.

19:50

And both Emma and Mate said

19:53

it's hard to prove this because it's an evolutionary

19:55

theory. But they're like, either

19:57

way, the thing that we're really

19:59

excited about is how this works.

20:01

What

20:04

are the mechanisms that allow bats

20:07

to beat viruses

20:10

and to live these long, long

20:12

healthy lives? Wouldn't

20:16

you like to be youthful until you die?

20:20

Not have the ravages

20:23

of aging.

20:24

Methuselah, Methuselah lived till

20:26

he was one that 916 and then just died. Does

20:29

living healthier longer? That's what we want to

20:31

do. Finding ways to be able

20:34

to, I suppose, tolerate

20:36

the damage of living for a much

20:38

longer time without it making us sick.

20:40

Our dream is to really

20:43

learn from bats to benefit humans, to

20:46

treat diseases.

20:48

So that's the exciting part of bear research

20:50

I feel.

20:53

It's really cool because I feel

20:56

like we tend to just

20:58

hear about certain animals in these very

21:01

particular lights.

21:03

That bats harbor viruses. But

21:06

they have their own bat lives. That

21:10

ultimately can help us to create, to

21:12

live our own human lives. It's ultimately

21:14

about us, though. Let's be real.

21:18

Thanks so much, Gloria.

21:19

Thanks, Wendy. Thanks for having me.

21:31

That's Science Versus. And before

21:33

you go, don't go anywhere because Flora

21:36

made this amazing video about

21:39

bats flying. It's just a

21:41

couple of minutes. It's beautiful. Go

21:43

find it on our Instagram, which is

21:45

science underscore vs. Or you

21:47

can find it on my TikTok, which is at

21:50

Wendy Zuckerman. And if

21:52

you are listening on Spotify, you can just see

21:54

it right there on Spotify.

21:56

Thanks so much, Flora, for making it. It's

21:58

gorgeous. Today's episode

22:01

had more than 70 citations

22:03

in it. And if you want to see them and learn more

22:05

about bats, then go to our show notes and

22:07

click on the link to the transcript. We

22:10

are racing down facts

22:12

and fuddies for next season, which is going to kick

22:14

off in September. But in

22:17

the meantime, in just a couple of weeks,

22:19

we're going to have the winners for you

22:22

for our inaugural favorite

22:24

science versus episode competition, which

22:27

we're calling fizz-zz-zz-ck

22:31

favorite science versus episode competition.

22:33

We are going to work on a title as well. First

22:36

up is the winner of the drug category,

22:39

your favorite episode that we've done about

22:41

drugs. And we've done quite a lot. Adderall,

22:43

Molly, Mushy's.

22:45

It was a hotly contested category.

22:53

This episode was produced by Flora Lichtman with

22:55

help from me, Wendy Zukerman, Joel Werner, Ari

22:57

Natavich, Michelle Dang, and Rose Rimmler. Editing

23:00

by Jorge Just, Annette Heist, and Blythe

23:02

Terrell. Fact-checking by Carmen Dral.

23:04

Mix and sound design by Bumi Hidako. Music

23:07

written by Billy Libby, Emma Munger, Dara

23:09

Hirsch, So Wylie, and Bobby Lord. Thanks

23:12

to everyone we reached out to for this episode, including

23:14

Dr. Vera Gorbanova, Dr.

23:17

Sharon Swartz, Dr. Jerry Wilkinson,

23:19

and Dr. Lisa Cooper. And

23:21

a little fact-check, a little Bible study

23:23

for my listeners, Methuselah lived

23:25

to 969 years old, not 960

23:29

years old. Science

23:32

Versus is a Spotify Studios original.

23:34

And if you're listening on Spotify, you should

23:37

tap the bell. There's a little bell

23:39

icon. And if you tap that, then you'll get new

23:41

notifications every time an episode comes

23:44

out. I'm Wendy Zukerman. Back to

23:46

you next time.