File TXT tidak ditemukan.
Transcript
poEfPCUbDus • Bat Superpowers | Full Documentary | NOVA | PBS
/home/itcorpmy/itcorp.my.id/harry/yt_channel/out/novapbs/.shards/text-0001.zst#text/1075_poEfPCUbDus.txt
Kind: captions
Language: en
[Music]
60 mi west of Bangkok is the Cowo Chong
Pran Cave. Famous throughout all of
Asia.
[Music]
For centuries, a sanctuary for the
faithful and now the curious.
Scientists who come to learn from the
most unusual of creatures.
[Music]
As the sun sets, 3 million bats begin to
stir, preparing for one of nature's
greatest spectacles.
Rocketing to the skies in a blizzard of
flapping wings, they will pass the
night, gorging on insects.
This epic nocturnal excursion is a feast
for the eyes.
But for science, bats are much more, a
biological treasure.
They are by far the most fascinating of
all animals.
They are remarkable and extraordinary
creatures.
>> As a biologist, it's my job to really
tell people that we we need the bats.
>> There are more than 1,400 different
species of bats playing crucial roles in
ecosystems all over the world.
But for many people, bats are the stuff
of nightmares.
>> Bats have been demonized in the society.
I thought bats were scary and creepy and
a little bit kind of unpleasant.
>> Already vilified in pop culture,
recent news reports have been giving
bats an especially dangerous rep.
>> The ancestor of the virus in humans had
to be a bat virus.
>> There is a virus that is 96% similar to
this new corona virus in bats. Early
research suggests human picked up the
corona virus from animals, possibly
bats. Though we still don't know the
exact source of the virus that started
the co pandemic, bats are a prime
suspect.
But rather than fear these flying
creatures, biologists are hailing them
as potential saviors.
They can really get infection without
getting sick.
Bats teach us lesson not to suffer
autoimmune disease, diabetes, arthritis.
>> Whether you capture a bat that is 2
years old or 15 or 20 years old, you
don't see any difference
>> for the body size of these animals. They
are way off scale in terms of their
longevity.
>> Bats hold the cure. They hold our
treatment.
>> Science is beginning to decipher their
strange powers. Could these much
maligned creatures hold precious secrets
for our own health?
Bat superpowers right now on Nova.
[Music]
As an American-based supplier to the
construction industry, Carlileo is
committed to developing a diverse
workplace that supports our employees
advancement into the next generation of
leaders. From the manufacturing floor to
the front office. Learn more at
carilele.com.
[Music]
Many experts believe that the corona
virus that tore through the world's
population in 2020 came from a bat.
[Music]
Biologist Superorn Wapulisadi is
worldrenowned for her ability to track
viruses in the wild.
Today, her team has come to test the
giant colony at Kao Chong Pran.
There are bats in the cave and we put
this on to be safe while we work.
>> It doesn't mean that there are deadly
viruses in there, but we need to protect
ourselves to do our work safely.
Once fully suited up, the scientists
descend deep into the cave. Under the
gaze of the Buddha statues, the team
installs a net in the large chamber that
local monks share year round with its
native residents.
>> We have been doing research work here
for more than 10 years. Now for safety
reasons we have come back to test if
there is corona virus which could be
dangerous for the people in the area.
A second team waits at the exit of the
cave to catch bats flying outside.
Tonight about 70 bats will miss their
nighttime excursion.
[Music]
Instead, they will spend a few hours in
a makeshift lab set up at the base of
the hill.
Each bat is given a careful medical
checkup.
Trying to limit stress to the animal,
scientists take multiple samples from
the skin, the mouth, and even the
intestines.
All organs that are susceptible to
containing viruses, known or unknown.
[Music]
>> We have discovered hundreds of viruses
in bats.
Actually,
there are more than 60 viruses in bats
that could eventually be transmitted to
human beings.
>> In addition to being a key transmitter
of the deadly rabies virus, bats are
suspected sources for numerous viral
outbreaks around the world.
The 1967 Marberg virus in Europe, two
waves of Ebola in Africa, the Hendra
virus in Australia,
the Nepa virus in Malaysia, then a
series of corona virus outbreaks, SARS
that started in China, MS in the Arabian
Peninsula, and now the CO 19 pandemic
that engulfed the planet in just a few
months.
For some scientists, it is a trend that
will no doubt continue. As human beings
encroach more and more on the bat's
natural habitat, Super Porn is hoping to
discover why viruses circulate so well
within bat colonies and how they might
transmit them to other animal species
that in turn could pass them on to
humans. But above all, she wants to know
why this animal infected by so many
dangerous viruses seems totally
impervious to their effects.
As far as I know from the research work
overseas and my research work here, bats
with viruses aren't getting sick.
>> The bat aren't getting sick while the
viruses still live within them.
[Music]
>> Because of the whole world is so
desperately trying to deal with with CO
19 and its horrible effects. Bats have
come into the limelight and they've come
into the limelight as potential
reservoirs for many, many viruses. And
the question is why?
Why can they? Are bats really special?
Is there something unique about bats
biology, their physiology, the genetics
that allows them to tolerate these
viruses? What's the reason?
Will studying bats allow us to avoid the
next deadly virus outbreak?
Could their diseased defying biology
help us to live longer and in better
health? Laboratories around the world
are mobilizing to find the answers.
Because just how this stealthy nocturnal
animal functions remains largely a
mystery.
[Music]
New Yorkers may not realize that one of
the most unique biological banks in the
world is just next door. A huge
collection of bat organs and tissues
stored at Stonybrook University.
A veritable treasure trove for
scientists like Liliana Davalos.
It's a piece of brain from biz.
This is um liver liver sample and it's
from Colombia. This is from our last
expedition.
Our collection has um everything from
the top of the head, the brain, the
nose, the eyes, uh and every organ in
the body.
Mummified bats, cabinets stuffed with
body parts. The Davalos lab might feel
like something out of a Frankenstein
film.
[Music]
Not to worry, it's not what you think.
And Liliana, rather than being
frightened or repelled by bats, is in
fact one of their biggest fans.
What have we got here?
Oh, this is so amazing. This is a
horseshoe bat.
This collection happened in 1934,
December 27th.
Somebody was out there in Shangdu in
China catching bats. This is the
horseshoe down here. You see it?
The horseshoe bat is widespread
throughout Asia and suspected to be at
the origin of SARS Cove 2, the virus
that causes CO 19.
[Music]
With this specimen, Liliana will be able
to study just how bats become infected.
Since CO is a respiratory disease, the
team concentrates their efforts on the
animals respiratory tract, especially
its nose and nasal cavities.
Could it be that the inside of this
strange looking nose contains the key to
how bat viruses also infect humans?
Thanks to Laurel Yo, a researcher at
nearby Yale University, the team has
access to a 3D scanner. It's the first
time ever this technique will be used to
study the inside of a bat.
Here are the teeth. You can see the
neurons in the teeth as we move through.
Here's the tongue.
Here's the nasal cavity.
The horseshoe bat's nose is of
particular interest to Liliana and her
spouse and research partner Angelique
Cortell, an expert in human biology.
>> Angelique studied the respiratory tracts
of CO victims at the height of the
pandemic.
>> The bat is very similar to humans
because you can see actually the same
structure of the nose.
Bats that are known to harbor the
closest relative to SARS COV 2 have a
nasal cavity that is the uh that is
actually closely uh resembling that of
human which is very likely part of the
reason why we can be infected so quickly
with SARS COV 2 because all of the
sudden um it's not completely strange
territory for a corona virus to enter to
the nasal cavity of a human.
>> But once it has arrived in the nose of a
bat or a human, how does the virus
infect the rest of the body? Liliana and
Angelique focus their research on the
cells that line the nasal cavity.
You see those hollow points in uh this
layer? Those are not holes. They are
cells. They're uh called the goblet
cells which are mucus producing cells.
They are the first barrier against
pathogens, against allergens, against
any kind of foreign bodies that enters
through the nose.
Mucus produced by goblet cells usually
traps viruses before they can enter the
body. But when it comes to CO 19, goblet
cells have a weakness. They are covered
by a receptor that the corona virus
recognizes. Like a key entering a lock,
the virus attaches to the receptor,
opens a passage, and injects its genetic
material. The cell then starts
manufacturing the virus by the hundreds,
starting a chain reaction that can
spread throughout the whole organism.
The corona virus can enter both bats and
humans in the same way through these
goblet cells.
So, how come humans can become so sick
while bats don't?
Our scientific understanding so far is
that the viral loads are fairly low,
meaning that these infections are
circulating, but they do not have the
same consequences in the bats that they
have in people. We do not understand yet
fully why.
>> Somehow, the virus is able to enter bats
noses the same way it does in humans.
But the similarities end there. In bats,
the virus is present, but at a
consistently low level.
The question is, how are bats keeping
the virus under control once it has
entered?
[Music]
That's what scientists in Singapore are
trying to find out at the Duke N US
Medical School, where the bat's immune
system has come under the microscope.
Professor Limpa Wang, known to
colleagues as Batman, thinks he has
found the secret to bat's super
immunity.
My students when they first work in my
lab they got it wrong. They said bats
has a more efficient immune system to
clear the virus. I said no bats have a
more efficient immune system not to
develop disease. They are more efficient
really to control the virus otherwise
they will not be good reservoir. Right?
>> Matei an wrote his thesis under Linda
Wang's direction. when he joined the
team in 2014. The lab did not yet have a
living bat colony to work with.
>> In the past, uh we have to fly over to
Australia to get our sample for our
studies. But now we have a local bat
colony right here and this allows us uh
to get the fresh sample easily and the
study bats really closely.
The cave nectar bat has a fox-like head
and lives principally in Southeast Asia.
In the wild, these bats are carriers of
many viruses, but don't get sick. But in
the lab, conditions are strictly
controlled and the animals remain
uncontaminated.
We are using the fresh B samples to
analyze their contents in details
starting from uh genes, mRNA, protein
cells to even tissues and all of these
component can be used and utilized to
study bats and their immune system.
Mati's experiment concentrates on
proteins involved in the immune response
and on one molecule in particular
interferon alpha.
[Music]
>> To be simple uh interferon alpha is a
key molecule that alerts the body to the
intruder. It tells the surrounding cells
that uh an infection is occurring.
When a cell detects a virus, it
unleashes a barrage of interferon
molecules which spread through the body,
spurring immune cells into action which
in turn wipe out the intruding pathogens
and get rid of the cells already
infected.
>> So we want to examine and compare uh the
level of interferonal production between
human cells uh before an infection
actually occurs.
So look look at this curve. Uh this
curve is a human sample. It's flat. It
means that interfering alpha is almost
undetectable. But in contrast the in our
best sample we have a lot of
interference alpha detected even though
there's no infection occurring right
there.
>> In other words, bats have adopted a
proactive strategy of defense.
Thanks to interferon being permanently
present, when a virus penetrates the
bat's body, their immune system is
already active. But in humans, that
reaction is much slower. While our
body's immune system is ramping up to
produce interfuron, the virus can be
spreading. The risk of getting sick is
therefore much greater in us than in
bats where the virus remains under
tighter control. Human, for example, our
defense system is switched off most of
the time until we see enemies and then
we switch on. Unlike us, the bat's
defenses are always on high alert. Their
immune system can prevent damaging
infection while letting some virus hang
around. That's good news for the bat,
but it might be really bad news for
humans.
>> One theory is that, you know, the virus
live inside a bat body. you know you
already have a elevated defense system.
So when they jump to a different host
like human and that's it's like you know
free playground for them and they just
go and rampage you know so very
efficient.
A virus that battles for survival inside
a bat's super immune system becomes a
formidable enemy
when it jumps to a less defended species
like a human. It's much more dangerous.
But why did bats develop such a highly
functioning immune system?
Why did nature bestow bats with a
superpower while our own defense system
has proven so weak in the face of
multiple epidemics?
[Music]
It's a question that zoologologist and
geneticist Emma Tealing has spent
decades researching.
Nearby her lab at University College
Dublin,
Emma takes advantage of the last few
days of fall to visit a local colony
before the bats start their winter
hibernation.
[Music]
And some people actually don't like
them. And the question is why? As
primates, we primarily get the
information from our environment through
our eyes. At night, we're a bit
frightened. We can't really see them.
People think, "Oh, they're going to get
caught in your hair." They they don't.
What they do is they're flying, feeding
on insects that are trying to bite you.
[Music]
There you go. There's the bat. More than
likely, it's a it's a Oh, hello, you
beauty.
More than likely, this is a soprano
piper strap because you can hear it pe
frequency is about 45 kHz. Do you see
that little bat fly across? This bat
detector is picking up the sound that's
being emitted from the bat's mouth. And
what's happening is a bat emits this
call and listen to the echoes and it
uses this to be able to orient
incomplete darkness. I have a head torch
on right now. Right now this is dusk.
You can't see anything but the bats have
woken up. They're flying around feeding
on the insects that are more than likely
flying up and down this small stream
here. Here. Bang. Bang. Bang. Bang.
Bang.
Aided by their unique capabilities, bats
thrive on every continent except
Antarctica. It's a story of
extraordinary adaptation, the secrets of
which are inscribed in their DNA.
A wing flap away is Emma's center of
operations, a laboratory of mamalian
molecular evolution. Equipped with the
latest tech, it's affectionately called
the Bat Lab. Here, Emma co-pilots one of
the largest studies of bats in the
world. The project BAT 1K connects over
a 100 scientists around the globe in a
joint effort to sequence the genomes of
the approximately 1,400 bat species. We
wanted to sequence the entire DNA code
that's in every single cell of a
particular species, but we wanted to do
it to the quality of the genomes that we
have for humans or or or mice so that we
could now use this to investigate the
likes of what have bats evolved to allow
them live with corona viruses and not
die.
[Music]
BAT 1K's approach is to compare the
billions of letters that make up bat's
genetic code with the DNA of other
mammals. In theory, finding out what is
different will lead researchers to those
parts of the bat genome responsible for
its robust health. Darwinian selection.
Did natural selection act on a
particular part of the genome and bats
that make it very different at this same
region in bats than everything else? And
this may indicate that this is the
region that's driving their unique
adaptations.
BAT 1K has already fully decoded the
genomes of six bat species. The velvety
freetailed bat, the greater horseshoe
bat, the Egyptian fruit bat, the pale
spearnosed bat, the greater mouseed bat,
and cools pipist.
A meticulous comparison of their DNA
with that of land-based mammals revealed
something totally unexpected.
When the bat's ancestor developed wings
and evolved the ability to fly at least
55 million years ago, the genes
controlling their immune system also
evolved, mutating significantly. It's as
if their evolution as flyers somehow
provoked or required a similar evolution
in their immune system.
They can fly. They're able to tolerate
all their these these unique viruses. Is
there a connection? What's the
connection? And this is something I've
been working on for a very long time. I
have written research grants. I've
gotten slammed. I've gotten abused left,
right, and center. It has caused such
scientific controversy, and it still
does. So, the idea is evolving. Could
evolving a new form of locomotion
drive an imological and a genetic
response, a physiological response? So,
I'm going to argue that yes, for Emma
Tealing, bat's extraordinary resistance
to viruses seems to have evolved
handinhand with their other superpower,
their supreme prowess in the air. But
how could flight protect this tiny
mammal from sickness? What is the link
between the two?
As the only mammals known to have
evolved true flight, bat's flying
technique is totally unique in the
animal kingdom.
Every year at the Freo Cave about 70 mi
west of San Antonio, Texas, newborn bat
pups will take to the skies for the very
first time.
[Music]
Millions of female Mexican free tailed
bats migrate here in the spring, and
it's the perfect opportunity for
biologist Gary McCracken to observe the
animals in action.
This is the time of year when uh mothers
are beginning to give birth to their
pups. We can't go very deep into the
cave with with any lights or cameras
because it's just too disruptive at this
time of year for for the for the bats.
So, we're respectful for that. Yeah.
Ready to go.
>> Gary goes just inside the mouth of the
cave so he won't disturb the pups.
>> I well remember the first time that um I
went into a Mexican freetailed batcave.
I thought I was on the surface of the
moon. I I mean really the the dust
covering the rocks. You you walk and
your footprints stay there and then they
get reworked by the beetles. The
atmosphere is heavy with simple
compounds of carbon and nitrogen,
methane and ammonia. I mean, it really
does seem like you're on another planet.
When I first saw the babies, the dense
concentrations of babies, it was just
amazing. Soon you've got four to 5,000
babies in an area of about a square
meter. Four to 5,000 babies.
>> After about a month clinging to the
walls, the young pups will attempt their
very first flight. The slightest error
could be fatal.
>> It's really awesome to imagine
what it must be like to take that first
flight. Looking down below,
thinking about what happens if I don't
make it. and and and if you don't make
it, you're not going to get back. You're
going to you're going to you're going to
land in the guano and and and be eaten
by domestic beetles.
And you know, the amazing thing is that
it seems that the vast majority of them
do make it work.
>> Once mature, the Mexican freetailed bat
develops into an extraordinarily
powerful flying machine. And it's their
outstanding performance in the air that
Gary has come here to measure.
Helping him is local biologist Jared
Holmes.
>> Yesterday they started flying about
7:30.
>> Uhhuh. Yeah. So we'll be ready by 7:30
for sure. Okay.
>> Yeah. We'll have the plane ready to go.
So I'll I'll uh tell you when we're
taking off and uh you get the bat ready
and stick the radio on it.
>> All right. These bats weigh a half an
ounce, 12 grams. They are too small, too
light with current technology to carry
uh GPS trackers, but they can carry
these little radios that are um
basically location locators.
>> And we're still looking for a female bat
of of average size.
>> Average size, not too pregnant.
>> Gotcha.
>> And u and obviously good health. A nice
plump one. Y a nice bat.
>> Okay.
>> The next day on the tarmac at
Garnerfield Airport, not far from Freo
Cave, Gary adjusts the settings of his
radio telemetry receiver. This device
will use radio signals to follow the bat
that Jared is about to capture and equip
with a transmitter.
[Music]
With the airplane, it is possible to
triangulate the location of the bat and
and by carefully listening to the signal
from the transmitter, um we're able to
pinpoint the location with some
precision.
>> Gary, the flight is started. Are you in
the air,
>> Jared? We're uh we're just taking off
right now.
>> We should be there in 15 minutes.
>> Okay, Roger that. I'm going to go ahead
and try to catch a bat. Sure to get a
nice young fluffy looking one.
[Music]
I got a couple on the net. One looks
good. I'm going to go ahead and tag it
and get it released.
>> This is working really well right now.
[Music]
>> Okay, Jared, we're coming. We're
approaching the zone. Approaching the
zone.
>> Got the signal.
We're right overhead.
>> Okay, you can release.
>> Releasing her now.
>> Gary, I see the plane. I hope the bat's
coming with you.
>> Okay. Okay. Okay. Okay. Got it. Got it.
Good.
When the bat flies just underneath the
plane, the radio signal gets stronger
and the pursuit begins. As soon as the
bat veers off, the signal weakens,
allowing Gary to guide the pilot to stay
on the bat's course.
>> Speed up just a little bit. Losing her.
Losing her little tight on top. Got it.
The plane is able to follow the bat for
3 hours as it circles the area, hunting
flying insects.
Now she's heading back north, heading
back in the direction of the cave.
I think our bat went home.
This is so cool. Wow. When radio
telemetry was used a few years ago, it
allowed scientists to track the Mexican
free tailed bat for the first time in
mid-flight with jaw-dropping results.
>> We knew the bats were flying long
distances. We knew that th this
particular type of bat can fly really,
really fast. Um, but we we didn't expect
to see this this sort of performance. We
think we've seen a bat going 100 miles
an hour.
After studying the data, initial field
observations were confirmed. The Mexican
freetailed bat got up to speeds of about
100 mph,
the fastest horizontal flight of any
animal ever recorded.
But even if bats have proved to be the
fastest flyers, how would that help them
to resist diseases?
[Music]
Back on Terra Burma, scientists at Brown
University are studying the possible
connections between bat flight and bat
health.
Kenny Brewer is an aeronautical engineer
and for the past 15 years he has been
creating mechanical wings that imitate
the bat's anatomy. His prototypes have
improved, but nothing comes close to the
real thing.
They have however helped him understand
the physical effort required for bats to
navigate the skies.
Flying is an expensive operation in
terms of energy. It takes a lot of
energy to get into the air and to propel
yourself. And you have to not only
generate your own thrust, but you have
to overcome the drag that is that is
experienced by your body and by your
wings.
Scientists estimate that the physical
effort expended by a bat in flight is
about three times more than a
terrestrial mammal of the same size
running at full speed. The heartbeat of
certain flying bats can reach 1,66 beats
per minute. Could
this level of activity unrivaled by any
other mammal somehow explain bat super
immunity?
A few measurements have suggested that
body temperature in bats might be
unusually high. This has led some
scientists to suggest that bats body
temperatures might be so high that it's
as if they
continually operate at feverlike
temperatures during their nightly
flights.
Fever is well known as a means of
fighting infection. High temperatures
slow down the replication of the virus
and boost the foot soldiers of the
immune system to devour intruders.
A feverish body is a hostile environment
for a virus.
So, could the extreme energy spent
during nightly hunting for rays cause a
spike in body temperature that would
protect bats from viruses? To know for
sure, scientists must collect data in
perfectly controlled conditions.
This is where the Egyptian fruit bat
comes in.
With its twoft wingspan, it is a
remarkable flying machine.
Equipped with expertly placed mini
thermometers, the animal takes flight
under the team's watchful eye.
>> Oh my god, that's not bad.
I'm very impressed.
>> Yeah.
[Music]
The experiment was performed on four
different bats and the result was
exactly the same for each one.
[Music]
We got these temperature traces for
three muscles along the bat wing. So the
red is a muscle that's in the core, the
pectoralis muscle, which is really
important for flight. And then we have
the biceps and a muscle in the forearm
of the bat. So closest to the core, and
then the blue curve is furthest from the
core. And as time proceeds, the red and
the green muscle stay pretty close to
the high body temperature that it
started with. But as we um move through
time, the blue muscle, the forearm
muscle that's further away from the core
gets really cold and stays cold as
they're flying. They're flapping their
wings. Um and so heat is going to be
wicked away from from the bat wings just
by virtue of of their movement. And so
bats are really effective at dumping
heat even if they're generating a lot.
And their body temperatures um stay
fairly normal.
[Music]
In other words, the naked wings of bats
act as an ultraefficient cooling system
that keeps their temperatures from
rising.
[Music]
There's no fever-like temperatures that
could explain their super immunity.
But some researchers are still convinced
that flight must have somehow helped
shape their immune system.
[Music]
>> It sounds like very promising. And uh
>> one believer is Limpa Wang and he thinks
he's found out how
>> there is a receptor expressing
>> especially in the very ancient bats when
they just acquired FL capability. The
number one challenge they had to deal
with is this high metabolism.
>> The high metabolism required for flight
should lead to inflammation. When
animals muscles work really hard, the
intense physical activity creates toxic
byproducts and these usually trigger
inflammation. Inflammation intrigues
lympa because it is also caused by viral
infections and in humans too much
inflammation can have devastating
effects. for other mammals, human
included when the coordination goes, you
know, out of window and when you
overdefense that actually cause the
pathology, you know, now you get
disease. So we have a cliche in our
field to say very few virus kills us, we
kill ourself.
>> This is what happened in some of the
most severe cases of CO 19 when patients
immune systems raged out of control with
so-called cytoine storms.
Cytoines, like interferons, are
molecules manufactured by the body to
regulate an immune response in case of
an attack. Sometimes the system goes
berserk and produces too many cytoines.
The resulting inflammation doesn't just
hurt the virus, but everything in its
path, including organs like the lungs,
heart, and even the brain.
But bats don't seem to experience these
symptoms.
So, have bats figured out a way to
control the inflammation associated with
both high metabolism and infection?
To find out, Wang's team is mixing bat
immune cells with toxic molecules that
in humans would trigger inflammation.
So actually we have isolated bad immune
cells and treated them with the toxic
substances that are produced by the body
when the metabolism is high.
In most animals like humans, these
toxins trigger the production of a
protein called NLRP3
which in turn ramps up the immune
response and inflammation.
This microscope reveals the presence of
the protein in the form of a red dot.
>> We are comparing the inflammatory
response between human and bat cells.
>> In the human cells, the red dot shows
that the protein is being produced,
meaning the immune response has begun.
But over on the bat side, there are no
red dots, meaning no protein and no
immune response. Their cells seem to
have tolerated the attack of the added
toxins without any immune reaction.
>> So the the bat have naturally dampen an
LP3 protein so that the stress related
and the viral induced inflammation
always stay under control.
>> To become successful flyers, bats had to
tamp down their response to the toxins
produced during flight and prevent
inflammation.
Limpa Wang thinks the same
anti-inflammatory chemistry is what's
preventing bats from overreacting to
viruses.
Bats are very good virus reservoirs. You
know we believe is that their adaptation
to flight. So that created a very
different uh immune system. Of course
that was evolved not to host virus per
se. That's evolved adaptation to flight.
So their ability to host virus is almost
like a byproduct in my view.
>> For the team in Singapore, this unique
adaptation isn't just an evolutionary
curiosity. It could pave the way to
revolutionary new therapies for all
sorts of human diseases that involve
inflammation
>> in COVID 19 infections and many age
related chronic diseases such as um
Alzheimer's, stroke, coronary artery
disease, um diabetes in all these
diseases inflammation is overactivated
that cause a lot of problem.
I'm really excited from a basic
scientist point of view is that we are
studying a very important mammal as a
model for living you know uh uh health
you know I mean to house living and the
longevity. Yeah.
>> This is the paradox of the bat held
responsible for a pandemic. Could the
bat also be the source of potential new
cures? Not just to fight disease, but
also old age. Could the bat, maligned
and misunderstood as it is, also teach
us the secret to growing old, healthier.
[Music]
This is began a village in Britany,
France, whose bell tower is a well-known
refuge for bats.
Every summer, dozens of female greater
mouse-eared bats roost in its rafters,
giving birth to their pups, a species
whose exceptional long lifespans
fascinate scientists like Eric Pat.
But he must wait for nightfall to spot
the newborns and their mothers.
>> With the greater mouse year bat, you
have to be patient. They don't come out
very early. So, we've often got to wait
a long time.
[Music]
We're in front of the exit.
In this colony, there's about 90 adults.
We're hearing something over there. I
think they're just behind the drain
pipe.
They're difficult to see, discreetly
slipping out from behind the drain pipe,
but a thermal camera reveals the frenzy
nocturnal ballet taking place around the
church.
[Music]
In the surrounding underbrush, this
nocturnal acrobat shows the full range
of its agility.
[Music]
The greater mouse earbat is known for
hunting between 12 and 24 in from the
ground. They listen for beles making
noise, walking through the underbrush.
As soon as they hear one, they jump on
top, grab hold of it, and fly off.
[Music]
But it's not their agile flight or
unusual hunting methods that have caught
the attention of scientists the world
over. It's their amazing longevity which
seems to defy the laws of nature.
[Music]
>> There is a general rule in biology.
Smaller animals don't live very long
while larger animals live much longer.
Mice live for a couple of years while
elephants can live dozens of years.
The oldest greater mouseeared bat ever
recorded was 37 years old. But the
record for longest life is actually held
by a cousin of the greater mouseeared
bat. The Bransbat weighs less than a
quart of an ounce. Yet researchers
captured a specimen that was at least 41
years old, a lifespan 10 times longer
than theoretically expected.
What's really fascinating with bats is
that if you capture an individual that
is 2 years old or one that is 15 or 20
years old, you can't see any difference
between the two. With humans, dogs, and
most other species, you would see an
individual that has aged.
>> Sebastian Pushmile studies aging at the
Institute of Evolutionary Science in
Mont Pelier, France.
[Music]
When we study aging, one of the first
things we look at is the central part of
the cell, which is shown here, the
nucleus.
Inside the nucleus, you see these kinds
of small X's. These are the chromosomes.
I've zoomed in on the most important
part of the chromosome here, its
extremities, which we see in red.
These are what we call telomeres.
So this telomeir is a long fragment that
is in charge of protecting the
chromosome's extremity.
On young cells the telomere is very long
and over time as the cell ages the
telomere gets shorter.
At some point it will get so short that
it will directly affect the integrity of
the chromosome and the health of the
cell.
Scientists think that the shortening of
telomeres over time is one of the key
triggers of cell death, influencing the
aging process and the lifespan of all
mamalian species.
[Music]
So what's the deal with bats?
For the past 10 years, the bat colony at
the church and began has been at the
heart of a study to figure out the
secret to bats long lives.
Every summer, Sebastian Pushmile meets
up with Emma Tealing and her team to
collect samples that allow them to
follow individual bats and their aging
process.
An implant gun is used to insert a
magnetic identification chip the size of
a grain of rice under the skin between
the shoulder blades. Dozens of juveniles
have been tagged this summer.
>> When we say tag, it means inserting
these tiny microchips like we do with
dogs and cats at the vet.
This allows us to recognize the same
individuals year after year and to
follow their aging.
>> The oldest tagged individuals are now 10
years old.
>> These are our sample numbers is what we
take back to UCD so we know who's who.
And there she is.
>> They're beautiful.
>> Gorgeous.
>> Now, is that a baby?
>> We're going to find out now in a minute.
>> Looks like an adult.
>> You want to bet?
>> You say baby or an adult?
>> Adult.
>> Okay. Okay. Can we will we check to see
by shining?
>> It's an adult. Now, we're going to take
the blood. Quite dark, isn't it?
>> Whether it's a drop of blood or a small
skin fragment, the samples taken every
year are conserved carefully in liquid
nitrogen.
>> You see how relaxed the bat is?
>> Yeah.
>> It doesn't hurt them at all. As long as
they're in capable hands of people who
know how to hold them properly and
correctly.
>> So, there it is.
Secret of everlasting youth.
>> Some of the precious samples taken and
began are stored in Sebastian's basement
laboratory in Mont Pelleier to see if
the greater mouseed bat's longevity
could be linked to the length of its
telomeres. Scientists have compared them
with those of the common bent-winged
bat, a species of bat that usually dies
before it reaches 20.
What you see with the common bent wing
bat which has a short lifespan is that
the telomeres shorten with age. You see
that very clear progression. On the
other hand, the greater mouse earbat
shows absolutely no shortening of the
telomeres. On the contrary, you can see
clearly that they remain constant as the
individual ages. So an individual bat
which is 10 years old or one year old,
the telomeres will be exactly the same
length. longer and
>> what we found was extraordinary in the
longest live genera bats the miotus bats
their tieumirs do not shorten with age
and this was very unique we didn't
really see this in any other mammal tie
shorten in us in badgers and sea lines
so this was extraordinary
Emma and Sebastian believe that the
greater mouseeared bat's extraordinarily
long life is linked to the resilience of
its telomeres
But how does this genetic material
withstand the passage of time?
To find out, scientists compared the
genes of the greater mouseed bat with
other mammals and uncovered some key
differences.
We found two or three genes that we
think are evolving in a different way in
bats that we think are the genes that
allow this thing called alternative tie
lengthening happen in bats. So bats are
able to use a different mechanism to
maintain their tieumirs with age. Are
these genes the key to the bat's long
and healthy lives? And could they one
day protect against the effects of aging
in humans as well? Scientists aren't
about to turn this discovery into an
elixir of youth, but researchers like
Emma are optimistic for the future.
Their adventure with bats has just
begun.
[Music]
Echolocation that allows them to see in
total darkness. Flight speed that is
unrivaled by any other animal. They are
impervious to most viruses. insensitive
to aging and the masters of a
marvelously controlled immune system.
Not bad for an animal so long despised.
[Music]
Looking at bats, one of the most
vilified and terrifying potentially of
all mammals, if we look at them in a
slightly different light, we will be
able to find ways to improve human
existence.
The product of millions of years of
adaptation, bats are now emerging from
the shadows as extraordinary creatures
that could potentially light a path for
longer and healthier human lives.
Heat. Heat.
[Music]
Heat. Heat.
[Music]
[Applause]
[Music]