00:00:00.000 --> 00:00:03.194
(upbeat music)

00:00:03.194 --> 00:00:07.277
(speaking in a foreign language)

00:00:09.729 --> 00:00:13.812
(speaking in a foreign language)

00:00:16.039 --> 00:00:19.671
(upbeat music continues)

00:00:19.671 --> 00:00:23.754
(speaking in a foreign language)

00:00:25.327 --> 00:00:28.744
(upbeat music continues)

00:00:35.870 --> 00:00:40.750
(speaking in a foreign language)

00:00:40.750 --> 00:00:43.350
(plane flying)

00:00:43.350 --> 00:00:47.433
(speaking in a foreign language)

00:00:51.763 --> 00:00:53.598
(upbeat music)

00:00:53.598 --> 00:00:57.827
(speaking in a foreign language)

00:00:57.827 --> 00:01:01.619
(upbeat music continues)

00:01:01.619 --> 00:01:05.702
(speaking in a foreign language)

00:01:16.107 --> 00:01:19.524
(upbeat music continues)

00:01:25.198 --> 00:01:29.281
(speaking in a foreign language)

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(speaking in a foreign language)

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(upbeat music)

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- [Narrator] Flight...

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In nature this mode of locomotion is

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the most complicated of all.

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From insects to pterosaur
and birds to bats.

00:01:58.050 --> 00:01:59.670
Their prowess for flight

00:01:59.670 --> 00:02:03.513
has defied scientific
explanation for centuries.

00:02:04.740 --> 00:02:07.350
- There's something
fundamentally mysterious yet

00:02:07.350 --> 00:02:09.513
about animal flight and how it works.

00:02:10.710 --> 00:02:11.970
- [Narrator] Using new techniques,

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and imaging, modeling, and robotics,

00:02:14.490 --> 00:02:17.190
researchers are shedding new light

00:02:17.190 --> 00:02:19.533
on the mysteries of animal flight.

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- We can study these animals

00:02:22.470 --> 00:02:23.880
and access them in ways

00:02:23.880 --> 00:02:26.433
that simply wasn't possible
10 or 20 years ago.

00:02:27.330 --> 00:02:31.110
- Our understanding of flight
has increased enormously.

00:02:31.110 --> 00:02:34.800
We now finally have
actual, quantitative data.

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- [Narrator] This understanding
means a new page is

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being written in the history

00:02:38.820 --> 00:02:41.340
of aeronautics inspired by nature.

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So are we now able to imitate animals

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to design flying machines
that perform better

00:02:47.310 --> 00:02:49.080
and are more economical?

00:02:49.080 --> 00:02:51.810
Will scientists from the 21st century

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finally achieve Leonardo da Vinci's dream?

00:02:54.994 --> 00:02:57.577
(upbeat music)

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To understand how flying
animals move through the air,

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we must first go back in time

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and take a look at the very first beings

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to conquer the skies, insects.

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- My name is Anne Miller,

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and I'm the paleontologist

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and geologist of Grand
Canyon National Park.

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My favorite thing about Grand Canyon is

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each rock formation that I'm looking at,

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I imagine myself there

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at the time when those
rocks were deposited.

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(upbeat music)

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These rock layers are almost

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like a book in the history of life,

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and each chapter reveals something about

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the evolution of life.

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(upbeat music continues)

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- [Narrator] For Anne Miller,

00:04:03.450 --> 00:04:05.760
the most fascinating chapter in time

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was almost 300 million years ago

00:04:08.670 --> 00:04:11.970
when insects were the
only masters of the sky.

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(upbeat music continues)

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Anne and her colleague, McKayla,

00:04:20.340 --> 00:04:23.995
are headed to an excavation
site to search for fossils.

00:04:23.995 --> 00:04:27.412
(upbeat music continues)

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- We're hoping to look
for an insect fossil,

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because this is so rare,

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and if we could find
more fossils of insects,

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it might give us more insight
into the evolution of insects,

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but also the evolution of powered flight.

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Okay, this looks like a good outcrop here.

00:04:51.270 --> 00:04:53.790
- [Narrator] At the beginning
of the 20th century,

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a superbly preserved insect
wing was excavated here.

00:05:01.110 --> 00:05:03.120
Anne is showing McKayla

00:05:03.120 --> 00:05:07.590
this 285 million year old fossil.

00:05:07.590 --> 00:05:08.590
- That's super cool.

00:05:11.673 --> 00:05:14.820
I love how well you can see
the venation in the wing.

00:05:14.820 --> 00:05:16.520
- Yeah.
- It's really remarkable.

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- [Narrator] This giant insect

00:05:19.740 --> 00:05:21.633
would've been the size of a blue tit.

00:05:22.710 --> 00:05:25.170
It belonged to the Meganeura group,

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distant cousins of the dragonfly.

00:05:27.390 --> 00:05:31.620
Like dragonflies, they flew
by beating their wings.

00:05:31.620 --> 00:05:35.250
- Being able to study this
specimen is really important,

00:05:35.250 --> 00:05:37.890
because it sort of marks the beginning

00:05:37.890 --> 00:05:41.950
of powered flight success
in the group of insects.

00:05:42.803 --> 00:05:45.090
- [Narrator] The Meganeura
of the Grand Canyon

00:05:45.090 --> 00:05:47.490
disappeared millions of years ago,

00:05:47.490 --> 00:05:49.440
but paleontologists have a way

00:05:49.440 --> 00:05:52.170
of understanding their
capacity for flight.

00:05:52.170 --> 00:05:56.910
- Since the venetian structure
of this Meganeuradae wing

00:05:56.910 --> 00:05:59.580
is very similar to the modern dragonfly,

00:05:59.580 --> 00:06:03.883
we have an idea of how this
insect was able to fly.

00:06:03.883 --> 00:06:06.466
(upbeat music)

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And so we know that
Meganeuradaes were very quick.

00:06:12.810 --> 00:06:13.890
They could hover.

00:06:13.890 --> 00:06:16.140
They could make very tight turns.

00:06:16.140 --> 00:06:20.064
These insects were really
excellent at flying.

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(upbeat music continues)

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They were the true masters
of the sky during that time.

00:06:31.560 --> 00:06:34.170
- [Narrator] This very efficient
flight was made possible

00:06:34.170 --> 00:06:36.243
thanks to the shape of their wings.

00:06:37.200 --> 00:06:38.280
- What's interesting about

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this venetian structure
of this Meganeura is

00:06:41.490 --> 00:06:45.870
that it's actually thicker
on the leading edge

00:06:45.870 --> 00:06:50.870
and the venation become parallel
towards the trailing edge,

00:06:51.810 --> 00:06:54.870
just like an aircraft
that we can see today.

00:06:54.870 --> 00:06:58.203
And that made the insect very aerodynamic.

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- [Narrator] Very early on,

00:07:00.150 --> 00:07:02.520
nature invented a streamlined wing,

00:07:02.520 --> 00:07:05.795
which we still find in
all flying animals today.

00:07:05.795 --> 00:07:08.378
(upbeat music)

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At the beginning of the 16th century,

00:07:16.530 --> 00:07:20.807
Leonardo da Vinci noticed this
unique wing shape in birds.

00:07:20.807 --> 00:07:24.890
(speaking in a foreign language)

00:07:49.080 --> 00:07:52.230
Today, our knowledge of
aerodynamics allows us

00:07:52.230 --> 00:07:54.810
to understand why flying animals develop

00:07:54.810 --> 00:07:56.910
this particular wing shape.

00:07:56.910 --> 00:08:00.870
It provides the best possible
penetration through the air.

00:08:00.870 --> 00:08:02.640
In this configuration,

00:08:02.640 --> 00:08:05.790
the air represented by these lines

00:08:05.790 --> 00:08:07.713
flows smoothly around the wing.

00:08:08.700 --> 00:08:12.090
If the thicker part of
the wing was at the back,

00:08:12.090 --> 00:08:14.340
turbulence would form behind it

00:08:14.340 --> 00:08:17.015
and hinder the motion of the animal.

00:08:17.015 --> 00:08:19.598
(upbeat music)

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At the time of the Meganeura
of the Grand Canyon,

00:08:28.620 --> 00:08:31.350
other flying insects populated the Earth.

00:08:31.350 --> 00:08:33.810
Anne Miller is continuing her research

00:08:33.810 --> 00:08:35.190
in the hope of documenting

00:08:35.190 --> 00:08:38.013
the early proliferation of winged insects.

00:08:43.740 --> 00:08:45.480
- The development of the wing

00:08:45.480 --> 00:08:48.150
was really important for insects,

00:08:48.150 --> 00:08:51.060
and what we see in the
fossil record is that,

00:08:51.060 --> 00:08:53.640
when that first wing appeared,

00:08:53.640 --> 00:08:55.530
we get kind of this burst

00:08:55.530 --> 00:08:58.862
of diversity in the
whole group of insects.

00:08:58.862 --> 00:09:01.020
(upbeat music)

00:09:01.020 --> 00:09:02.250
- [Narrator] Flying insects are

00:09:02.250 --> 00:09:05.250
the most diverse group
of animals on the planet.

00:09:05.250 --> 00:09:07.680
This astounding evolutionary success

00:09:07.680 --> 00:09:09.510
was made possible by mastering

00:09:09.510 --> 00:09:12.870
so-called active flight or powered flight,

00:09:12.870 --> 00:09:16.164
flight which relies on
the beating of wings.

00:09:16.164 --> 00:09:20.356
(upbeat music continues)

00:09:20.356 --> 00:09:22.856
(bird flying)

00:09:27.090 --> 00:09:30.603
The majority of flying animals
make use of active flight,

00:09:31.980 --> 00:09:33.840
but beating their wings requires

00:09:33.840 --> 00:09:36.300
a tremendous amount of effort.

00:09:36.300 --> 00:09:38.580
How has nature created animals

00:09:38.580 --> 00:09:42.240
that are able to travel in
this way with such ease?

00:09:42.240 --> 00:09:43.350
To understand,

00:09:43.350 --> 00:09:45.030
we must take a closer look at

00:09:45.030 --> 00:09:47.913
the most striking example
of this evolution,

00:09:48.750 --> 00:09:49.818
birds.

00:09:49.818 --> 00:09:52.401
(upbeat music)

00:09:58.560 --> 00:10:01.080
The Field Museum in Chicago is renowned

00:10:01.080 --> 00:10:04.046
for its research into
the evolution of animals.

00:10:04.046 --> 00:10:07.590
(upbeat music continues)

00:10:07.590 --> 00:10:10.200
Paleontologist Jingmai O'Connor is

00:10:10.200 --> 00:10:13.803
one of the top specialists on
the origin of flight in birds.

00:10:16.620 --> 00:10:17.790
- [Jingmai] Birds are really

00:10:17.790 --> 00:10:20.220
incredible, fascinating creatures.

00:10:20.220 --> 00:10:22.620
They're one of the most modified groups

00:10:22.620 --> 00:10:23.790
of animals on the planet.

00:10:23.790 --> 00:10:25.740
I mean, they're so modified,

00:10:25.740 --> 00:10:27.780
because of their adaptations for flight,

00:10:27.780 --> 00:10:30.330
though we didn't even
recognize them to be reptiles

00:10:30.330 --> 00:10:31.683
until fairly recently.

00:10:33.480 --> 00:10:35.460
- [Narrator] Reptiles adapted by nature

00:10:35.460 --> 00:10:37.394
for the necessity of flight.

00:10:37.394 --> 00:10:39.977
(upbeat music)

00:10:44.760 --> 00:10:47.010
To uncover this metamorphosis,

00:10:47.010 --> 00:10:48.000
we have to return

00:10:48.000 --> 00:10:51.480
to the time when dinosaurs
ruled over the Earth.

00:10:51.480 --> 00:10:54.210
- Behind me, we have, Sue, the T-Rex.

00:10:54.210 --> 00:10:57.630
It is the world's most
complete adult T-Rex

00:10:57.630 --> 00:10:58.950
that has ever been collected.

00:10:58.950 --> 00:11:02.448
So it's about 66 to 68 million years old.

00:11:02.448 --> 00:11:05.865
(upbeat music continues)

00:11:14.670 --> 00:11:16.860
- [Narrator] T-Rexes like Sue are

00:11:16.860 --> 00:11:20.583
the distant cousins of
eagles, pigeons, and swallows.

00:11:22.170 --> 00:11:25.200
In fact, all birds are dinosaurs,

00:11:25.200 --> 00:11:29.133
the only ones to have survived
the fifth mass extinction.

00:11:30.990 --> 00:11:33.690
Tyrannosaurus and birds
have a common ancestor

00:11:33.690 --> 00:11:37.320
who lived 170 million years ago.

00:11:37.320 --> 00:11:38.730
- So we don't know exactly

00:11:38.730 --> 00:11:40.530
what this animal would've looked like,

00:11:40.530 --> 00:11:43.050
but we know that it would've
been a bipedal animal.

00:11:43.050 --> 00:11:45.720
so an animal that's walking on the ground,

00:11:45.720 --> 00:11:47.340
definitely not flying.

00:11:47.340 --> 00:11:51.483
It would've been bigger than
this, but smaller than T-Rex.

00:11:54.300 --> 00:11:56.550
- [Narrator] So the ancestor of birds

00:11:56.550 --> 00:11:58.023
was a walking dinosaur.

00:11:59.160 --> 00:12:01.950
To get from this animal
to the birds of today

00:12:01.950 --> 00:12:03.000
required a series

00:12:03.000 --> 00:12:05.763
of phenomenal modifications
made over time.

00:12:07.380 --> 00:12:09.960
Jingmai O'Connor can trace this evolution

00:12:09.960 --> 00:12:11.403
thanks to fossils.

00:12:12.570 --> 00:12:14.280
What were the transformations

00:12:14.280 --> 00:12:16.928
that made powered flight possible?

00:12:16.928 --> 00:12:18.810
(upbeat music)

00:12:18.810 --> 00:12:23.190
The history of birds began
more than 230 million years ago

00:12:23.190 --> 00:12:26.790
in a group of two-legged
dinosaurs called Theropods.

00:12:26.790 --> 00:12:28.920
150 million years ago,

00:12:28.920 --> 00:12:32.280
a lineage of small Theropods
developed long arms

00:12:32.280 --> 00:12:34.350
out of which large feathers grew.

00:12:34.350 --> 00:12:36.510
These were the very first birds.

00:12:36.510 --> 00:12:38.580
Their archaic wings only allowed them

00:12:38.580 --> 00:12:40.950
to glide in a rudimentary fashion.

00:12:40.950 --> 00:12:44.160
Over time, their tailbone disappeared

00:12:44.160 --> 00:12:46.170
and their bodies became squatter.

00:12:46.170 --> 00:12:49.950
But most importantly, their
wing bones became stronger.

00:12:49.950 --> 00:12:53.220
They became a solid structure
that was able to resist

00:12:53.220 --> 00:12:55.860
the pressure of the first powered flights.

00:12:55.860 --> 00:12:57.330
50 million years ago,

00:12:57.330 --> 00:12:59.790
the modern bird made its first appearance.

00:12:59.790 --> 00:13:02.850
It had a powerful engine
to count on for flying,

00:13:02.850 --> 00:13:04.710
enormous pectoral muscles,

00:13:04.710 --> 00:13:08.160
which allowed it to beat its
wings harder and for longer,

00:13:08.160 --> 00:13:11.280
millions of years to get all the elements

00:13:11.280 --> 00:13:13.681
for powered flight in place.

00:13:13.681 --> 00:13:17.098
(upbeat music continues)

00:13:22.560 --> 00:13:25.060
(bird flying)

00:13:26.670 --> 00:13:30.360
To fly, birds muscles need lots of fuel,

00:13:30.360 --> 00:13:33.213
sugar, fat, and oxygen.

00:13:35.970 --> 00:13:38.160
How do these animals provide their bodies

00:13:38.160 --> 00:13:40.053
with massive amounts of oxygen?

00:13:42.690 --> 00:13:44.250
The respiratory system

00:13:44.250 --> 00:13:48.270
of the first birds has
long remained a mystery.

00:13:48.270 --> 00:13:51.660
But Jingmai O'Connor has
recently lifted the lid

00:13:51.660 --> 00:13:54.510
on this unknown part of evolution.

00:13:54.510 --> 00:13:55.343
- I would argue that

00:13:55.343 --> 00:13:57.900
to understand the
evolution of avian flight,

00:13:57.900 --> 00:14:01.590
the soft tissue modifications
are more significant

00:14:01.590 --> 00:14:04.500
than the skeletal transformations
that paleontologists

00:14:04.500 --> 00:14:07.010
typically track through the fossil record.

00:14:07.010 --> 00:14:08.070
(upbeat music)

00:14:08.070 --> 00:14:10.440
- [Narrator] The problem
is that soft tissue is

00:14:10.440 --> 00:14:12.243
much more difficult to study.

00:14:13.140 --> 00:14:17.185
Its fossilization is an
extremely rare phenomenon.

00:14:17.185 --> 00:14:21.300
Jingmai was lucky enough
to work on this specimen.

00:14:21.300 --> 00:14:25.320
128 million year old archaeopteryx fossil

00:14:25.320 --> 00:14:28.053
in an unprecedented state of preservation.

00:14:29.160 --> 00:14:30.060
- This was really weird.

00:14:30.060 --> 00:14:32.670
This is something I'd never before seen.

00:14:32.670 --> 00:14:34.170
We see that this tissue kind of forms,

00:14:34.170 --> 00:14:36.090
like, two paired structures

00:14:36.090 --> 00:14:39.150
and that it's intimately embedded around

00:14:39.150 --> 00:14:42.960
the thoracic ribs like
the rib cage essentially.

00:14:42.960 --> 00:14:44.190
It's in the area of the lungs.

00:14:44.190 --> 00:14:45.150
It's paired.

00:14:45.150 --> 00:14:46.170
Maybe it's lungs.

00:14:46.170 --> 00:14:49.920
So we wanted to investigate
this strange tissue further.

00:14:49.920 --> 00:14:51.060
What we decided to do

00:14:51.060 --> 00:14:53.820
was use a scanning electron microscopy.

00:14:53.820 --> 00:14:55.260
- [Narrator] This device reveals

00:14:55.260 --> 00:14:57.952
the flying machine's hidden resources.

00:14:57.952 --> 00:15:00.535
(upbeat music)

00:15:01.650 --> 00:15:03.240
- What we found was really cool.

00:15:03.240 --> 00:15:04.290
What you're seeing here is

00:15:04.290 --> 00:15:06.150
basically the soft tissue of the lung

00:15:06.150 --> 00:15:07.810
that has been fossilized.

00:15:07.810 --> 00:15:10.260
(upbeat music continues)

00:15:10.260 --> 00:15:11.640
- [Narrator] These are the oldest

00:15:11.640 --> 00:15:14.100
bird lungs ever discovered.

00:15:14.100 --> 00:15:17.580
The picture exceeded all
Jingmai's expectations.

00:15:17.580 --> 00:15:20.130
It revealed a much more complex structure

00:15:20.130 --> 00:15:22.590
than she had ever imagined.

00:15:22.590 --> 00:15:26.040
- Their lung tissue is
extremely subdivided,

00:15:26.040 --> 00:15:27.030
which you can see here.

00:15:27.030 --> 00:15:29.250
You can see all these little pockets.

00:15:29.250 --> 00:15:30.330
And what that does is

00:15:30.330 --> 00:15:33.990
it increases the surface area of the lung

00:15:33.990 --> 00:15:36.270
and the surface area is

00:15:36.270 --> 00:15:38.970
where the oxygen is being absorbed.

00:15:38.970 --> 00:15:40.950
So, if you increase the surface area,

00:15:40.950 --> 00:15:42.690
you increase the amount of oxygen

00:15:42.690 --> 00:15:45.000
that the lung tissue can absorb.

00:15:45.000 --> 00:15:47.850
- [Narrator] The arrival of
these super lungs enabled

00:15:47.850 --> 00:15:51.099
the enormous effort
required for powered flight.

00:15:51.099 --> 00:15:53.682
(upbeat music)

00:15:55.410 --> 00:15:58.050
The work done by paleontologists shows

00:15:58.050 --> 00:16:00.930
to what point nature has
optimized animals' bodies

00:16:00.930 --> 00:16:02.778
to fight against gravity.

00:16:02.778 --> 00:16:06.195
(upbeat music continues)

00:16:13.260 --> 00:16:14.820
Other scientists working at

00:16:14.820 --> 00:16:17.280
the intersection of
biology and engineering

00:16:17.280 --> 00:16:20.583
are interested in the physical
principles of animal flight.

00:16:21.510 --> 00:16:23.910
They want to know how the
beating of their wings

00:16:23.910 --> 00:16:26.523
enables flying animals to stay in the air.

00:16:27.790 --> 00:16:30.240
A question that Leonardo da Vinci was

00:16:30.240 --> 00:16:34.140
already asking at the
end of the 15th century.

00:16:34.140 --> 00:16:37.230
- There's a really beautiful
Leonardo da Vinci quote,

00:16:37.230 --> 00:16:40.740
which essentially says that
in order to understand flight,

00:16:40.740 --> 00:16:43.728
you have to understand
what the air is doing.

00:16:43.728 --> 00:16:45.780
(upbeat music)

00:16:45.780 --> 00:16:48.120
The idea of that interdependence,

00:16:48.120 --> 00:16:51.120
the dependence of birds on
the movements of the air,

00:16:51.120 --> 00:16:53.370
I found, well, I got hooked on that.

00:16:53.370 --> 00:16:55.470
So I've been working on flight ever since.

00:16:56.880 --> 00:16:59.610
- [Narrator] Emily Shepard
is conducting her research at

00:16:59.610 --> 00:17:01.998
Swansea University in Wales.

00:17:01.998 --> 00:17:05.250
(upbeat music continues)

00:17:05.250 --> 00:17:07.980
She is preparing this pigeon called Dougie

00:17:07.980 --> 00:17:09.840
for an experimental flight

00:17:09.840 --> 00:17:12.523
by placing adhesive markers on her body.

00:17:12.523 --> 00:17:15.940
(upbeat music continues)

00:17:17.231 --> 00:17:19.110
- Looking good, Dougie.

00:17:19.110 --> 00:17:20.550
- [Narrator] The researcher wants to know

00:17:20.550 --> 00:17:24.150
how the interaction between
the air and Dougie's wings

00:17:24.150 --> 00:17:26.373
enables the pigeon to resist gravity.

00:17:27.360 --> 00:17:29.730
- So by measuring the
movements of these markers,

00:17:29.730 --> 00:17:32.730
we can understand the motion of the wings,

00:17:32.730 --> 00:17:35.520
and then how that translates
into the movement of the body,

00:17:35.520 --> 00:17:37.771
and how the birds maintaining altitude.

00:17:37.771 --> 00:17:39.660
(upbeat music)

00:17:39.660 --> 00:17:42.060
- [Narrator] To follow
Dougie's flight with precision,

00:17:42.060 --> 00:17:44.790
Emily isn't going to let
her out into the wild.

00:17:44.790 --> 00:17:48.240
Instead, she'll make her fly in the lab.

00:17:48.240 --> 00:17:49.073
To do this,

00:17:49.073 --> 00:17:50.670
the researcher is going to use

00:17:50.670 --> 00:17:52.593
an exceptional piece of equipment,

00:17:53.580 --> 00:17:58.203
a 20 ton machine that can
blow air at very high speeds.

00:18:00.270 --> 00:18:02.850
- It's really exciting to be
able to use this wind tunnel

00:18:02.850 --> 00:18:06.060
to provide more insight into bird flight.

00:18:06.060 --> 00:18:10.140
And what we're trying to do is
trying to provide a baseline

00:18:10.140 --> 00:18:15.140
to understand how birds fly
in controlled conditions.

00:18:15.147 --> 00:18:18.564
(upbeat music continues)

00:18:27.810 --> 00:18:28.920
- [Narrator] The wind tunnel works

00:18:28.920 --> 00:18:30.633
like a treadmill for birds.

00:18:31.470 --> 00:18:35.784
Dougie is facing a wind
of 50 kilometers per hour.

00:18:35.784 --> 00:18:39.201
(upbeat music continues)

00:18:45.810 --> 00:18:47.970
The exercise lasts for a few minutes

00:18:47.970 --> 00:18:50.370
during which time the
pigeon beats its wings

00:18:50.370 --> 00:18:51.543
to keep in position.

00:18:52.380 --> 00:18:55.743
The bird's movements are
registered with great precision.

00:18:58.380 --> 00:19:00.240
- We've got a series of seven cameras,

00:19:00.240 --> 00:19:02.370
infrared cameras around the area,

00:19:02.370 --> 00:19:05.430
and they flood the test
section with infrared light,

00:19:05.430 --> 00:19:09.360
and then they record things
which reflect the light,

00:19:09.360 --> 00:19:12.300
so the markers that we put on her wings.

00:19:12.300 --> 00:19:13.740
This enables us to record

00:19:13.740 --> 00:19:16.560
the position of those
markers 200 times a second.

00:19:16.560 --> 00:19:18.540
So we have plenty of,

00:19:18.540 --> 00:19:19.980
and we can resolve the movements

00:19:19.980 --> 00:19:22.906
of her wings in really high detail.

00:19:22.906 --> 00:19:25.489
(upbeat music)

00:19:30.810 --> 00:19:32.193
- Once the flight is over,

00:19:33.240 --> 00:19:35.883
Emily Shepard takes a
look at the recordings.

00:19:37.530 --> 00:19:39.960
- These are some of the motion
captured data that we have

00:19:39.960 --> 00:19:41.790
for Dougie flying in the wind tunnel.

00:19:41.790 --> 00:19:44.100
We can get a whole range of
parameters from these data,

00:19:44.100 --> 00:19:45.120
but two of the key things

00:19:45.120 --> 00:19:47.820
that we're interested in
are the wing beat frequency

00:19:47.820 --> 00:19:49.504
and the wing beat amplitude.

00:19:49.504 --> 00:19:52.620
(upbeat music)

00:19:52.620 --> 00:19:54.720
- This data gives Emily a better

00:19:54.720 --> 00:19:56.493
understanding of Dougie's flight.

00:19:57.660 --> 00:19:59.610
To keep themselves in the air,

00:19:59.610 --> 00:20:02.523
animals have to oppose their own weight.

00:20:03.540 --> 00:20:05.880
Faced with a pull towards Earth,

00:20:05.880 --> 00:20:08.040
the secret of flying animals rests

00:20:08.040 --> 00:20:12.420
upon the physics principle
of action and reaction.

00:20:12.420 --> 00:20:16.563
Every action has an equal
and opposite reaction.

00:20:17.910 --> 00:20:21.060
In this way, when flying
animals beat their wings,

00:20:21.060 --> 00:20:24.690
they move a large amount of air downwards.

00:20:24.690 --> 00:20:27.210
In reaction, the air produces

00:20:27.210 --> 00:20:31.383
an upwards force on the wings called lift.

00:20:33.390 --> 00:20:36.000
If you put your hand
out of the car window,

00:20:36.000 --> 00:20:38.850
you can also feel this force.

00:20:38.850 --> 00:20:41.130
- So you know that if you're moving along,

00:20:41.130 --> 00:20:45.540
if you angle your hand so
it's deflecting air downwards,

00:20:45.540 --> 00:20:48.360
you can feel your hand
starting to move upwards.

00:20:48.360 --> 00:20:50.760
And that's because by
deflecting air downwards,

00:20:50.760 --> 00:20:52.050
you are generating an equal

00:20:52.050 --> 00:20:55.410
and opposite reaction,
which is generating lift

00:20:55.410 --> 00:20:56.850
- [Narrator] To overcome gravity,

00:20:56.850 --> 00:20:59.880
flying animals have mastered
the manipulation of air

00:20:59.880 --> 00:21:01.560
through which they are moving.

00:21:01.560 --> 00:21:04.950
But flight is not just a
case of staying in the air.

00:21:04.950 --> 00:21:07.260
Other much more critical phases of flight

00:21:07.260 --> 00:21:09.333
pose a challenge to researchers.

00:21:10.620 --> 00:21:12.960
- Even the most accomplished flyers must

00:21:12.960 --> 00:21:15.420
sometimes come back to the surface.

00:21:15.420 --> 00:21:17.280
And this means that they have to be able

00:21:17.280 --> 00:21:20.580
to take off in the first
place as well as land safely.

00:21:20.580 --> 00:21:23.640
So there's a range of different
problems they have to solve

00:21:23.640 --> 00:21:26.580
in addition to just staying in the air.

00:21:26.580 --> 00:21:28.170
And for large flying animals,

00:21:28.170 --> 00:21:31.519
the biggest challenge is typically launch.

00:21:31.519 --> 00:21:34.102
(upbeat music)

00:21:36.780 --> 00:21:38.550
- [Narrator] Scientists have long thought

00:21:38.550 --> 00:21:40.420
that the heavier an animal was

00:21:41.610 --> 00:21:43.893
the harder it was for them to take off.

00:21:46.920 --> 00:21:50.433
But an extreme example now
calls this theory into question.

00:21:52.453 --> 00:21:53.640
(dinosaur flying)

00:21:53.640 --> 00:21:56.760
- Pterosaurs were flying reptiles

00:21:56.760 --> 00:21:58.500
closely related to dinosaurs,

00:21:58.500 --> 00:22:00.600
though not dinosaurs themselves.

00:22:00.600 --> 00:22:02.520
What they're really famous for is

00:22:02.520 --> 00:22:06.663
having generated the largest
flying animals of all time.

00:22:07.980 --> 00:22:11.520
So the idea that a 300 kilo animal

00:22:11.520 --> 00:22:13.240
could launch and fly at all

00:22:14.550 --> 00:22:16.920
defies most of our reasoning

00:22:16.920 --> 00:22:21.063
and defied our ability to
understand it for decades.

00:22:23.100 --> 00:22:26.040
- [Narrator] 70 million
years before birds,

00:22:26.040 --> 00:22:28.050
Pterosaurs were the first vertebrates

00:22:28.050 --> 00:22:29.673
to gain powered flight.

00:22:31.398 --> 00:22:33.351
(dinosaur growling)

00:22:33.351 --> 00:22:35.934
(upbeat music)

00:22:39.150 --> 00:22:41.100
These reptiles disappeared at

00:22:41.100 --> 00:22:43.230
the same time as the dinosaurs.

00:22:43.230 --> 00:22:45.870
So how can we study the
takeoff of an animal

00:22:45.870 --> 00:22:47.463
that no longer exists?

00:22:50.280 --> 00:22:53.580
This is the question asked by Tim Quady.

00:22:53.580 --> 00:22:56.665
He runs Blue Rhino Studio in Minneapolis.

00:22:56.665 --> 00:23:00.082
(upbeat music continues)

00:23:09.570 --> 00:23:12.810
Here the best paleoartists
in the United States

00:23:12.810 --> 00:23:15.003
sculpt life-size animals.

00:23:16.089 --> 00:23:19.506
(upbeat music continues)

00:23:23.490 --> 00:23:24.840
- How's everything fitting?

00:23:25.920 --> 00:23:27.660
- The lift seems--

00:23:27.660 --> 00:23:29.160
- [Narrator] And it's a flying animal,

00:23:29.160 --> 00:23:32.730
the Pterosaur that has
made the studio a success.

00:23:32.730 --> 00:23:35.580
After years of depicting
Pterosaurs in flight,

00:23:35.580 --> 00:23:39.243
Tim and his team have set
themselves a new challenge.

00:23:40.170 --> 00:23:41.910
- We've been really
fascinated by the idea of

00:23:41.910 --> 00:23:45.720
how these animals would
be able to take off.

00:23:45.720 --> 00:23:47.370
How would they launch themselves?

00:23:47.370 --> 00:23:49.500
What are the biomechanics
to make that work?

00:23:49.500 --> 00:23:50.610
We need to find somebody

00:23:50.610 --> 00:23:52.590
who can answer those questions for us

00:23:52.590 --> 00:23:54.330
and explain that process,

00:23:54.330 --> 00:23:58.230
because someday we would like
to depict that sculpturally.

00:23:58.230 --> 00:24:00.081
Hey, Michael.
- Hey, Tim.

00:24:00.081 --> 00:24:02.640
(Tim chuckling)
How you doing, Tim?

00:24:02.640 --> 00:24:04.980
- [Narrator] Tim has
called upon Michael Habib,

00:24:04.980 --> 00:24:08.070
a specialist in the
biomechanics of flight.

00:24:08.070 --> 00:24:10.050
- This is wild.

00:24:10.050 --> 00:24:11.550
- Yeah.
- This is wild.

00:24:11.550 --> 00:24:13.320
And you, like, made another world in here.

00:24:13.320 --> 00:24:14.620
This is, like--
- Yeah.

00:24:14.620 --> 00:24:16.341
Bit by bit. What do you think?

00:24:16.341 --> 00:24:19.890
- I feel like I just took a time machine

00:24:19.890 --> 00:24:21.840
going through the door.

00:24:21.840 --> 00:24:22.680
Can you show me

00:24:22.680 --> 00:24:24.900
where you've got your--
- Yeah. Yeah.

00:24:24.900 --> 00:24:26.256
Check that baby out.

00:24:26.256 --> 00:24:28.008
(Michael chuckling)

00:24:28.008 --> 00:24:29.103
- Oh, man.

00:24:29.970 --> 00:24:32.760
It's so different when
you see it up close.

00:24:32.760 --> 00:24:35.025
It's a whole different experience.

00:24:35.025 --> 00:24:38.130
(upbeat music)

00:24:38.130 --> 00:24:40.977
- [Narrator] This is
quetzalcoatlus northropi,

00:24:42.480 --> 00:24:45.423
one of the biggest
Pterosaurs ever discovered.

00:24:46.950 --> 00:24:50.850
A giant of the sky as
big as a fighter jet.

00:24:50.850 --> 00:24:53.130
It's such a huge animal that

00:24:53.130 --> 00:24:55.260
its ability to fly at all

00:24:55.260 --> 00:24:57.983
has long been debated among scientists.

00:24:57.983 --> 00:25:01.230
(upbeat music continues)

00:25:01.230 --> 00:25:03.030
Michael Habib has proven that,

00:25:03.030 --> 00:25:04.440
despite its size,

00:25:04.440 --> 00:25:07.140
the quetzalcoatlus could take off.

00:25:07.140 --> 00:25:09.840
He has shown that giant Pterosaurs

00:25:09.840 --> 00:25:12.243
didn't take off in the same way as birds.

00:25:14.280 --> 00:25:16.650
Birds take off from two feet.

00:25:16.650 --> 00:25:20.654
Their back legs provide the
drive to leave the ground.

00:25:20.654 --> 00:25:24.071
(upbeat music continues)

00:25:30.000 --> 00:25:33.450
Michael's discoveries have
led other biomechanists

00:25:33.450 --> 00:25:35.520
to reconstruct all the movements needed

00:25:35.520 --> 00:25:37.320
for a quadrupedal launch

00:25:37.320 --> 00:25:39.589
rather than a bipedal one.

00:25:39.589 --> 00:25:43.260
(dinosaur growling)

00:25:43.260 --> 00:25:45.000
From a four-legged position,

00:25:45.000 --> 00:25:47.283
the Pterosaur would crouch down,

00:25:48.330 --> 00:25:51.510
bend over, and then tip forward.

00:25:51.510 --> 00:25:53.910
It would be at this precise moment

00:25:53.910 --> 00:25:55.470
that all the tension gathered

00:25:55.470 --> 00:25:57.510
in the tendons of the upper limbs

00:25:57.510 --> 00:26:01.143
would slacken to catapult
the animal into the air.

00:26:04.560 --> 00:26:07.764
The whole sequence would
take less than a second.

00:26:07.764 --> 00:26:11.181
(upbeat music continues)

00:26:19.170 --> 00:26:21.960
- The thing that's
grabbing me is the speed,

00:26:21.960 --> 00:26:25.340
because in my head it just
seems like this would be...

00:26:26.370 --> 00:26:27.690
It seems like they would need to come

00:26:27.690 --> 00:26:30.360
to the edge of something to fall off,

00:26:30.360 --> 00:26:32.520
you know, to have that time,

00:26:32.520 --> 00:26:35.853
not just to explosively take
off and move so quickly.

00:26:37.470 --> 00:26:38.550
They'd be frightening.
- Yeah.

00:26:38.550 --> 00:26:40.117
- I mean, they would be
absolutely frightening.

00:26:40.117 --> 00:26:41.200
(both laughing)
- Terrifying animals.

00:26:41.200 --> 00:26:42.510
- Yeah.
- I mean, for an animal

00:26:42.510 --> 00:26:43.343
that tall,

00:26:43.343 --> 00:26:46.350
for something that is the
height of a living giraffe--

00:26:46.350 --> 00:26:48.240
- Yeah.
- To explode

00:26:48.240 --> 00:26:50.740
into the air in under a second, you know?

00:26:50.740 --> 00:26:51.740
- Yeah.
- You know,

00:26:52.595 --> 00:26:53.820
a similar time interval

00:26:53.820 --> 00:26:56.200
to how fast you or I could throw a kick.

00:26:56.200 --> 00:26:57.450
- Yeah.

00:26:57.450 --> 00:26:59.065
- Yeah. It's amazing.

00:26:59.065 --> 00:27:01.648
(upbeat music)

00:27:28.440 --> 00:27:30.060
- [Narrator] As science progresses,

00:27:30.060 --> 00:27:33.783
flying animals reveal their
secrets to us little by little,

00:27:34.920 --> 00:27:38.193
but these masters of the
sky are not done amazing us.

00:27:39.600 --> 00:27:43.083
These creatures aren't
content just traveling by air.

00:27:44.280 --> 00:27:48.240
They also carry out astonishing
feats while they do so,

00:27:48.240 --> 00:27:53.160
setting records of speed,
altitude, and distance.

00:27:53.160 --> 00:27:54.840
Over the past few years,

00:27:54.840 --> 00:27:57.120
scientists have recorded performances

00:27:57.120 --> 00:27:59.403
that were thought to be impossible.

00:28:01.170 --> 00:28:04.680
- We've been able to do
some work using airplanes

00:28:04.680 --> 00:28:08.820
to follow Brazilian free-tail
bats that have radio trackers.

00:28:08.820 --> 00:28:11.490
And it was astonishing
to us to learn that,

00:28:11.490 --> 00:28:13.650
at their highest speeds,

00:28:13.650 --> 00:28:17.400
these bats are approaching
100 miles per hour.

00:28:17.400 --> 00:28:22.400
It's truly remarkable
and really mind boggling.

00:28:22.436 --> 00:28:25.050
(upbeat music)

00:28:25.050 --> 00:28:28.050
These are the highest flight
speeds that have been recorded

00:28:28.050 --> 00:28:30.619
for any animal under powered flight.

00:28:30.619 --> 00:28:34.036
(upbeat music continues)

00:28:40.290 --> 00:28:43.497
- One of the other truly
incredible feats of flight is

00:28:43.497 --> 00:28:45.360
the barheaded geese that migrate

00:28:45.360 --> 00:28:48.330
over the peaks of the
highest Himalayan mountains.

00:28:48.330 --> 00:28:52.560
They've been seen flying over
8,000 meters in altitude.

00:28:52.560 --> 00:28:53.490
And what we know is

00:28:53.490 --> 00:28:56.220
that they have some very
specialized adaptations

00:28:56.220 --> 00:28:57.711
that allow them to do that.

00:28:57.711 --> 00:28:59.180
(upbeat music)

00:28:59.180 --> 00:29:01.680
(bird flying)

00:29:05.378 --> 00:29:07.961
(birds flying)

00:29:08.880 --> 00:29:10.740
Their muscle fibers are different.

00:29:10.740 --> 00:29:13.200
Some of their cell types
are different than geese

00:29:13.200 --> 00:29:15.780
that don't ever make
those kinds of flights.

00:29:15.780 --> 00:29:18.180
And that just tells you

00:29:18.180 --> 00:29:21.540
the kind of pressures
that are exerted on birds

00:29:21.540 --> 00:29:23.850
and that they must be able to respond to

00:29:23.850 --> 00:29:26.550
in order to perform
the feats that they do.

00:29:26.550 --> 00:29:29.133
(upbeat music)

00:29:31.710 --> 00:29:34.140
- [Narrator] Studies into
these incredible exploits

00:29:34.140 --> 00:29:36.630
always raise the same question.

00:29:36.630 --> 00:29:40.743
How do flying animals achieve
such levels of performance?

00:29:42.630 --> 00:29:45.070
One answer can be found in Alaska

00:29:47.010 --> 00:29:51.323
where birds push the
boundaries of animal endurance.

00:29:51.323 --> 00:29:54.073
(person running)

00:30:00.360 --> 00:30:02.553
- I like to push myself while I run.

00:30:07.440 --> 00:30:08.760
I like to find my limits.

00:30:08.760 --> 00:30:12.088
And I like to understand
what influences those limits.

00:30:12.088 --> 00:30:14.671
(upbeat music)

00:30:16.260 --> 00:30:18.690
And I'm trying to do the
same thing with birds.

00:30:18.690 --> 00:30:21.600
I want to know what influences

00:30:21.600 --> 00:30:24.593
how far and fast they can make migrations.

00:30:24.593 --> 00:30:28.010
(upbeat music continues)

00:30:30.180 --> 00:30:31.170
- [Narrator] Nathan Senner is

00:30:31.170 --> 00:30:33.243
an extreme migration specialist.

00:30:34.800 --> 00:30:36.330
For the past 10 years,

00:30:36.330 --> 00:30:39.750
he has spent his summers in
Beluga in Southern Alaska

00:30:39.750 --> 00:30:40.980
to discover the secrets of

00:30:40.980 --> 00:30:43.140
one of the world's toughest birds,

00:30:43.140 --> 00:30:45.447
the Hudsonian godwit.

00:30:45.447 --> 00:30:48.030
(upbeat music)

00:30:50.550 --> 00:30:54.090
- The non-stop flights
that godwits have exhibited

00:30:54.090 --> 00:30:56.130
are the longest flights that we know of,

00:30:56.130 --> 00:30:58.249
of any bird species in the world.

00:30:58.249 --> 00:31:00.480
(upbeat music continues)

00:31:00.480 --> 00:31:02.610
- [Narrator] Every year,
the godwits migrate

00:31:02.610 --> 00:31:04.983
from the south of Chile to Alaska,

00:31:06.030 --> 00:31:08.790
an exceptional transcontinental journey

00:31:08.790 --> 00:31:12.292
of almost 15,000 kilometers.

00:31:12.292 --> 00:31:15.709
(upbeat music continues)

00:31:20.910 --> 00:31:23.460
Nathan Senner and his team want to know

00:31:23.460 --> 00:31:27.411
how these birds manage
such a long migration.

00:31:27.411 --> 00:31:29.994
(upbeat music)

00:31:42.490 --> 00:31:44.990
- [Nathan] Okay, she's
gonna post up in that tree.

00:31:46.944 --> 00:31:51.180
- [Narrator] Lindy is a
female Hudsonian godwit.

00:31:51.180 --> 00:31:53.790
She's getting ready to sit on her eggs.

00:31:53.790 --> 00:31:57.693
Her nest is on the ground
camouflaged by these long grasses.

00:31:59.310 --> 00:32:03.720
For their research, the
scientists must catch Lindy.

00:32:03.720 --> 00:32:07.110
Last year, they attached a tag to her leg.

00:32:07.110 --> 00:32:09.690
They must recover it at all costs

00:32:09.690 --> 00:32:12.453
or the data on the bird's
journey will be lost.

00:32:13.440 --> 00:32:16.200
- [Nathan] Well, keep an
eye peeled on that spot

00:32:16.200 --> 00:32:19.263
in case does just fly out.

00:32:21.630 --> 00:32:24.480
- [Narrator] They must
first locate her nest

00:32:24.480 --> 00:32:27.960
as the capture can only take
place when she's brooding,

00:32:27.960 --> 00:32:29.643
as she won't be on her guard.

00:32:30.660 --> 00:32:31.530
- [Nathan] We lost it.

00:32:31.530 --> 00:32:33.300
I saw it go down.

00:32:33.300 --> 00:32:34.710
Did you see it?
- Where is it?

00:32:34.710 --> 00:32:36.773
- Flying or is it the
one you're talking about?

00:32:36.773 --> 00:32:38.910
- Yeah, I hear one calling.

00:32:38.910 --> 00:32:40.310
It sounds like she's flying.

00:32:41.670 --> 00:32:43.293
- Flying to the east right now.

00:32:46.050 --> 00:32:48.286
- [Narrator] Lindy has disappeared.

00:32:48.286 --> 00:32:49.860
(upbeat music)

00:32:49.860 --> 00:32:52.080
The researchers change tactics.

00:32:52.080 --> 00:32:53.160
They go over the bog

00:32:53.160 --> 00:32:55.863
with a fine tooth comb to find her nest.

00:32:56.793 --> 00:33:00.210
(upbeat music continues)

00:33:02.280 --> 00:33:05.613
- So let's get this stretch right here.

00:33:09.865 --> 00:33:11.490
(upbeat music)

00:33:11.490 --> 00:33:13.860
Our project really revolves around

00:33:13.860 --> 00:33:16.710
us being able to find godwit nests.

00:33:16.710 --> 00:33:18.360
So, if we're not finding nests,

00:33:18.360 --> 00:33:19.497
we're not getting data.

00:33:19.497 --> 00:33:22.053
And the bog isn't exactly
easy to walk through.

00:33:24.870 --> 00:33:27.320
Now that might be the bird
we really want though.

00:33:29.443 --> 00:33:30.457
- [Speaker] This is the bird?

00:33:30.457 --> 00:33:31.290
- Yeah.

00:33:33.450 --> 00:33:35.550
We got a bird with a geolocator.

00:33:35.550 --> 00:33:36.570
Here it is.

00:33:36.570 --> 00:33:37.830
I am incredibly happy.

00:33:37.830 --> 00:33:39.930
This is a bird that we have been tracking

00:33:39.930 --> 00:33:42.600
for four or five years now.

00:33:42.600 --> 00:33:45.600
So this is great data
just to be able to get

00:33:45.600 --> 00:33:48.153
that many repeated migrations from it.

00:33:50.430 --> 00:33:53.583
- [Narrator] Nathan can now
recover the geolocation tag.

00:33:55.560 --> 00:33:58.440
- Because their legs are
the most delicate part,

00:33:58.440 --> 00:34:00.993
We have to be extremely careful here.

00:34:08.070 --> 00:34:08.903
There we go.

00:34:10.080 --> 00:34:12.360
Miniaturized tracking
devices have absolutely

00:34:12.360 --> 00:34:15.510
revolutionized our
understanding of bird migration.

00:34:15.510 --> 00:34:18.330
You know, previously we
had to depend on somebody

00:34:18.330 --> 00:34:21.300
hopefully seeing a bird
somewhere in the world

00:34:21.300 --> 00:34:23.550
to know sort of where they went.

00:34:23.550 --> 00:34:25.890
In this one gram device,

00:34:25.890 --> 00:34:29.550
it has locations that a bird was

00:34:29.550 --> 00:34:32.043
every single day over the past year.

00:34:33.150 --> 00:34:36.990
But importantly, we have to
collect the geolocator again

00:34:36.990 --> 00:34:38.250
to get that data from it.

00:34:38.250 --> 00:34:39.900
It's not transmitting it anywhere.

00:34:39.900 --> 00:34:41.940
It's all just captured right here.

00:34:41.940 --> 00:34:44.944
So this is a really
important piece for us.

00:34:44.944 --> 00:34:49.944
(upbeat music)
(bird flying)

00:34:54.630 --> 00:34:55.620
- [Narrator] In their shelter,

00:34:55.620 --> 00:34:59.310
the researchers extract
the data from the tag.

00:34:59.310 --> 00:35:02.400
The device has been
recording changes in sunlight

00:35:02.400 --> 00:35:05.073
every five minutes for the past year.

00:35:06.690 --> 00:35:09.690
These measurements linked
to positions on the globe

00:35:09.690 --> 00:35:12.510
enable the scientists
to track the migration

00:35:12.510 --> 00:35:15.600
from the island of Chiloe in Chile.

00:35:15.600 --> 00:35:17.850
- I just love watching the data roll in.

00:35:17.850 --> 00:35:20.550
You know that, like, something
is going to be there.

00:35:20.550 --> 00:35:23.103
The process has been successful.

00:35:25.020 --> 00:35:26.610
All right, let's look at the map.

00:35:26.610 --> 00:35:30.120
So this bird stopped just
one time in Nebraska.

00:35:30.120 --> 00:35:33.767
So that's about, I think
10,000 kilometers from Chiloe.

00:35:35.924 --> 00:35:37.920
- [Narrator] 10,000 kilometers, five days

00:35:37.920 --> 00:35:40.530
without the slightest
break to eat or sleep.

00:35:40.530 --> 00:35:43.410
Following a stopover in the
center of the United States,

00:35:43.410 --> 00:35:46.020
Lindy finished her journey in one go,

00:35:46.020 --> 00:35:48.930
another 4,000 kilometers without stopping,

00:35:48.930 --> 00:35:51.600
a feat of endurance, but also speed.

00:35:51.600 --> 00:35:53.490
The data indicates that the bird flew at

00:35:53.490 --> 00:35:57.090
a speed of 70 kilometers
an hour on average.

00:35:57.090 --> 00:36:00.720
- That bird was just hauling.

00:36:00.720 --> 00:36:02.760
And it must have had
one heck of a tailwind

00:36:02.760 --> 00:36:05.760
in order to be able to
make the flight that fast.

00:36:05.760 --> 00:36:07.620
- [Narrator] By combining
data on the winds

00:36:07.620 --> 00:36:10.200
in the Pacific Ocean with the bird's root,

00:36:10.200 --> 00:36:12.150
Nathan and the other researchers

00:36:12.150 --> 00:36:14.700
have been able to explain
one of the secrets

00:36:14.700 --> 00:36:16.413
of this long distance flight.

00:36:17.520 --> 00:36:20.130
- One of the really mind blowing
things that we've learned

00:36:20.130 --> 00:36:22.140
is about the ability of birds

00:36:22.140 --> 00:36:24.150
to make use of winds in flight.

00:36:24.150 --> 00:36:26.880
They seem to know where the
different wind regimes are.

00:36:26.880 --> 00:36:28.680
They seem to know how to use them,

00:36:28.680 --> 00:36:31.590
and those wind regimes
make their migration

00:36:31.590 --> 00:36:35.430
so much more easy than
it would be otherwise.

00:36:35.430 --> 00:36:36.930
- [Narrator] To conserve their energy,

00:36:36.930 --> 00:36:39.390
the Hudsonian godwits are able to make use

00:36:39.390 --> 00:36:42.395
of the most favorable winds
on their long journey.

00:36:42.395 --> 00:36:44.978
(upbeat music)

00:36:49.500 --> 00:36:52.350
In aeronautics, the endurance
of flying animals is

00:36:52.350 --> 00:36:54.690
inspiring energy saving technologies

00:36:54.690 --> 00:36:56.552
that could shake up air travel.

00:36:56.552 --> 00:37:00.540
(upbeat music continues)

00:37:00.540 --> 00:37:03.060
In the 20th century, we conquered the air,

00:37:03.060 --> 00:37:05.100
but paid an astronomical price

00:37:05.100 --> 00:37:06.840
in terms of energy spent.

00:37:06.840 --> 00:37:09.840
Today we've hit a brick
wall with this model.

00:37:09.840 --> 00:37:11.730
Aviation must reinvent itself

00:37:11.730 --> 00:37:14.193
in order to reduce its
impact on the environment.

00:37:15.300 --> 00:37:16.740
Over the coming decades,

00:37:16.740 --> 00:37:20.340
the industry will be trying
to reach an ambitious goal,

00:37:20.340 --> 00:37:22.203
zero emission air travel.

00:37:23.310 --> 00:37:25.516
But how will they do this?

00:37:25.516 --> 00:37:28.590
Denis Darracq, an
aerodynamicist at Airbus,

00:37:28.590 --> 00:37:31.147
is one of those searching for answers.

00:37:31.147 --> 00:37:35.230
(speaking in a foreign language)

00:37:47.283 --> 00:37:49.866
(upbeat music)

00:37:55.590 --> 00:37:57.870
And flying animals could hold the key

00:37:57.870 --> 00:37:59.613
to this disruptive innovation.

00:38:00.750 --> 00:38:02.070
Their bodies are adapted

00:38:02.070 --> 00:38:04.967
to keep energy expenditure to a minimum.

00:38:04.967 --> 00:38:08.384
(upbeat music continues)

00:38:11.220 --> 00:38:14.220
Scientists are going back
to the foundations laid

00:38:14.220 --> 00:38:17.170
by Leonardo da Vinci for inspiration.

00:38:17.170 --> 00:38:20.587
(upbeat music continues)

00:38:29.640 --> 00:38:32.100
In Milan, the team at the Leonardo Museum

00:38:32.100 --> 00:38:34.650
are putting the finishing
touches to a machine

00:38:34.650 --> 00:38:38.643
that embodies all of Leonardo's
bio-inspired methodologies.

00:38:39.485 --> 00:38:40.606
(wheel moving)

00:38:40.606 --> 00:38:44.689
(speaking in a foreign language)

00:38:55.594 --> 00:38:57.720
(upbeat music)

00:38:57.720 --> 00:39:00.120
Through his flying machine project,

00:39:00.120 --> 00:39:03.453
Leonardo wanted to send a
message to his successors.

00:39:05.656 --> 00:39:09.739
(speaking in a foreign language)

00:39:35.250 --> 00:39:37.770
This invitation to be inspired by nature

00:39:37.770 --> 00:39:41.130
has echoed loudly through a
new generation of scientists

00:39:41.130 --> 00:39:43.943
who want to decarbonize aeronautics.

00:39:43.943 --> 00:39:46.526
(upbeat music)

00:39:52.230 --> 00:39:53.063
- Oh, wow.

00:39:55.740 --> 00:39:57.290
The whole tree is full of them.

00:39:58.350 --> 00:40:00.710
So, in Germany, it's much more common...

00:40:01.860 --> 00:40:04.920
The hooded crow is much
more common in Germany,

00:40:04.920 --> 00:40:07.320
while in France, for example,

00:40:07.320 --> 00:40:10.449
the carrying crow is
the predominant species.

00:40:10.449 --> 00:40:13.866
(upbeat music continues)

00:40:17.790 --> 00:40:20.550
- [Narrator] In Berlin,
engineer Lukas Killian is

00:40:20.550 --> 00:40:23.040
taking inspiration from the wings of crows

00:40:23.040 --> 00:40:25.893
for his research into
the economics of flying.

00:40:30.450 --> 00:40:32.070
At the crow's wingtips,

00:40:32.070 --> 00:40:35.280
the space between their
feathers form slots.

00:40:35.280 --> 00:40:38.250
This is a sophisticated
aerodynamic surface

00:40:38.250 --> 00:40:41.640
that we're only just
beginning to understand.

00:40:41.640 --> 00:40:44.758
- An amazing miracle of
biomechanic engineering.

00:40:44.758 --> 00:40:47.040
(upbeat music)

00:40:47.040 --> 00:40:48.900
- [Narrator] Do these slots enable crows

00:40:48.900 --> 00:40:51.157
to reduce the energy they expend?

00:40:51.157 --> 00:40:54.574
(upbeat music continues)

00:40:58.140 --> 00:40:59.160
To test this theory,

00:40:59.160 --> 00:41:02.040
Lucas has thrown himself
into a scientific adventure

00:41:02.040 --> 00:41:03.270
that has turned his outlook

00:41:03.270 --> 00:41:05.883
on the aerodynamics of birds upside down.

00:41:07.620 --> 00:41:10.650
- This project started
two and a half years ago,

00:41:10.650 --> 00:41:12.180
so it was a lot of hard work.

00:41:12.180 --> 00:41:13.980
There were many prototypes,

00:41:13.980 --> 00:41:15.300
many issues to fix,

00:41:15.300 --> 00:41:16.500
many points where I thought

00:41:16.500 --> 00:41:19.317
maybe this project isn't possible.

00:41:19.317 --> 00:41:22.734
(upbeat music continues)

00:41:24.420 --> 00:41:26.910
- [Narrator] Lucas adopted
a bio-inspired approach

00:41:26.910 --> 00:41:29.493
and has developed an
artificial crow's wing.

00:41:30.780 --> 00:41:32.760
- This approach is very similar to that

00:41:32.760 --> 00:41:35.097
adopted by Leonardo da Vinci 500 years ago

00:41:35.097 --> 00:41:38.580
was the process from looking at nature

00:41:38.580 --> 00:41:40.704
to building an actual
engineering prototype.

00:41:40.704 --> 00:41:43.287
(upbeat music)

00:41:44.400 --> 00:41:46.260
- [Narrator] Today,
Lukas is putting together

00:41:46.260 --> 00:41:48.525
the latest version of his invention.

00:41:48.525 --> 00:41:51.942
(upbeat music continues)

00:41:55.920 --> 00:41:58.500
This model, which is the
most complete so far,

00:41:58.500 --> 00:41:59.700
mimics the structure

00:41:59.700 --> 00:42:02.107
and the main movements of a crow's wing.

00:42:02.107 --> 00:42:05.524
(upbeat music continues)

00:42:07.500 --> 00:42:10.080
- So now when we have all
feathers on the prototype

00:42:10.080 --> 00:42:11.403
and we extend the wing,

00:42:12.630 --> 00:42:14.430
we see that the primaries

00:42:14.430 --> 00:42:18.923
start forming very distinct slots,

00:42:20.670 --> 00:42:23.100
and this is caused through the replication

00:42:23.100 --> 00:42:25.143
of the imagination of the feathers.

00:42:26.002 --> 00:42:29.419
(upbeat music continues)

00:42:30.420 --> 00:42:33.357
- [Narrator] Now the engineer
has to test his prototype.

00:42:33.357 --> 00:42:36.774
(upbeat music continues)

00:42:38.072 --> 00:42:43.072
(door opening)
(upbeat music continues)

00:42:43.920 --> 00:42:46.920
Using the wind tunnel at the
Technical University of Berlin,

00:42:46.920 --> 00:42:50.130
he can study the aero dynamism
of his mechanical wing

00:42:50.130 --> 00:42:52.622
as if it has evolved in the air.

00:42:52.622 --> 00:42:55.205
(upbeat music)

00:43:02.580 --> 00:43:05.130
- The setup here is basically the same

00:43:05.130 --> 00:43:07.050
as if the bird was flying through the sky.

00:43:07.050 --> 00:43:09.180
We have the fluid moving over the wing.

00:43:09.180 --> 00:43:12.270
It's the same as if the wing
was moving through the fluid.

00:43:12.270 --> 00:43:13.680
And then it's mounted

00:43:13.680 --> 00:43:17.011
to a balance which can measure
the aerodynamic forces.

00:43:17.011 --> 00:43:20.428
(upbeat music continues)

00:43:23.610 --> 00:43:25.710
- [Narrator] To determine
the role of the slots,

00:43:25.710 --> 00:43:29.938
Lukas will measure one force
in particular, the drag.

00:43:29.938 --> 00:43:32.521
(upbeat music)

00:43:35.103 --> 00:43:38.130
Drag is the manifestation
of air resistance.

00:43:38.130 --> 00:43:39.780
It opposes thrust,

00:43:39.780 --> 00:43:42.453
the force which moves
the bird through the air.

00:43:43.410 --> 00:43:44.490
At the wingtips,

00:43:44.490 --> 00:43:47.580
a component of drag called induced drag

00:43:47.580 --> 00:43:49.680
is associated with vortices,

00:43:49.680 --> 00:43:53.283
which disrupt airflow and slow
movement down considerably.

00:43:55.446 --> 00:43:58.770
(airplane flying)

00:43:58.770 --> 00:44:01.470
This phenomenon is very
important on airliners

00:44:01.470 --> 00:44:04.590
as it causes energy
expenditure that adds up

00:44:04.590 --> 00:44:08.073
to millions of liters
of kerosene every year.

00:44:10.092 --> 00:44:13.009
(machine starting)

00:44:18.232 --> 00:44:20.820
(wind blowing)

00:44:20.820 --> 00:44:23.793
It's the moment of truth
for Lucas's mechanical wing.

00:44:25.320 --> 00:44:28.953
Will the experiment reveal
a reduction in induced drag?

00:44:30.570 --> 00:44:34.484
The engineer presents his
results to a supervisor.

00:44:34.484 --> 00:44:38.567
(speaking in a foreign language)

00:44:56.190 --> 00:44:58.710
So what caused this difference?

00:44:58.710 --> 00:45:01.710
To understand, you have
to visualize the airflow

00:45:01.710 --> 00:45:04.953
using a piece of thread placed
in the trail of the wing.

00:45:07.680 --> 00:45:12.090
When the prototype is folded,
the thread turns at top speed.

00:45:12.090 --> 00:45:15.303
This shows there's a strong
vortex at the wing tip.

00:45:17.460 --> 00:45:20.280
On the other hand, when the
prototype is stretched out,

00:45:20.280 --> 00:45:23.493
any turbulence is much
more difficult to identify.

00:45:24.390 --> 00:45:28.137
- We're trying to find the
vortices on the wingtips.

00:45:34.949 --> 00:45:39.243
Here I found one, but it's very weak.

00:45:40.380 --> 00:45:42.210
They dissipate almost immediately.

00:45:42.210 --> 00:45:44.855
And you cannot follow
them downstream at all.

00:45:44.855 --> 00:45:47.438
(upbeat music)

00:45:50.910 --> 00:45:52.440
- [Narrator] By doing this experiment,

00:45:52.440 --> 00:45:55.680
Lukas has shown that the
slots break up the vortices

00:45:55.680 --> 00:45:57.303
that form at the wing tips.

00:45:59.040 --> 00:46:01.950
This fragmentation
creates smaller vortices

00:46:01.950 --> 00:46:04.177
and so reduces induced drag.

00:46:04.177 --> 00:46:07.594
(upbeat music continues)

00:46:10.830 --> 00:46:13.680
Thanks to this incredible
invention by nature,

00:46:13.680 --> 00:46:15.060
birds with slotted wings

00:46:15.060 --> 00:46:17.546
can reduce their energy expenditure.

00:46:17.546 --> 00:46:20.963
(upbeat music continues)

00:46:23.490 --> 00:46:26.670
In aeronautics, the feathers
from these birds' wing tips

00:46:26.670 --> 00:46:30.467
have inspired very efficient
energy saving devices.

00:46:30.467 --> 00:46:33.884
(upbeat music continues)

00:46:35.490 --> 00:46:38.280
For example, bio-inspired wing tip devices

00:46:38.280 --> 00:46:41.583
that fight against turbulence
and reduce fuel consumption.

00:46:44.340 --> 00:46:46.800
But manufacturers want to go even further

00:46:46.800 --> 00:46:50.070
and are now focusing on
the structure of the wings.

00:46:50.070 --> 00:46:52.743
As they're very rigid,
they waste a lot of energy.

00:46:53.850 --> 00:46:55.440
To fix this problem,

00:46:55.440 --> 00:46:57.030
engineers hope to unlock

00:46:57.030 --> 00:47:01.593
the masters of the sky's ultimate
secret, deformable wings.

00:47:02.550 --> 00:47:04.260
Also called morphing,

00:47:04.260 --> 00:47:07.770
this idea was first identified in 1505

00:47:07.770 --> 00:47:10.759
by the Father of bioinspiration.

00:47:10.759 --> 00:47:14.842
(speaking in a foreign language)

00:47:31.590 --> 00:47:34.740
The creation of wings that
can change their shape is

00:47:34.740 --> 00:47:36.480
the holy grail of engineers

00:47:36.480 --> 00:47:39.570
who are designing the
airplanes of tomorrow.

00:47:39.570 --> 00:47:42.990
To achieve it, they must
understand morphing in animals.

00:47:42.990 --> 00:47:44.700
In a series of manuscripts,

00:47:44.700 --> 00:47:47.610
Leonardo da Vinci described the superpower

00:47:47.610 --> 00:47:50.973
in the most agile of
flying animals, the bat,

00:47:51.900 --> 00:47:53.280
- Leonardo da Vinci,

00:47:53.280 --> 00:47:57.540
in his notes, he writes
about bats and insects.

00:47:57.540 --> 00:48:00.030
And he discusses how

00:48:00.030 --> 00:48:04.050
the flexible and living
wing membranes of bats

00:48:04.050 --> 00:48:06.510
was likely crucial to their ability

00:48:06.510 --> 00:48:09.240
to make these tight, rapid turn maneuvers

00:48:09.240 --> 00:48:11.580
to be able to capture insects.

00:48:11.580 --> 00:48:14.970
I'm not sure if da Vinci was
able to actually see that

00:48:14.970 --> 00:48:17.640
or how much he actually observed,

00:48:17.640 --> 00:48:21.300
but today we can slow
down these interactions.

00:48:21.300 --> 00:48:24.600
We can see in great
detail how bats maneuver,

00:48:24.600 --> 00:48:27.270
how they use their wing membrane

00:48:27.270 --> 00:48:30.840
or their tail to scoop up an insect prey.

00:48:30.840 --> 00:48:35.040
And not surprisingly, da Vinci was

00:48:35.040 --> 00:48:37.530
hundreds of years ahead of his time,

00:48:37.530 --> 00:48:40.861
and we are just catching
up to his ideas today.

00:48:40.861 --> 00:48:43.444
(upbeat music)

00:48:44.520 --> 00:48:47.576
- [Narrator] Every night a
fight kicks off in the sky.

00:48:47.576 --> 00:48:50.993
(upbeat music continues)

00:48:54.810 --> 00:48:58.354
A fight for survival
between bats and moths.

00:48:58.354 --> 00:49:01.771
(upbeat music continues)

00:49:07.050 --> 00:49:09.753
In the Chiricahua Mountains in Arizona,

00:49:10.590 --> 00:49:14.550
a team of scientists led by
biologist, Aaron Corderan,

00:49:14.550 --> 00:49:17.220
record the flying performances of bats

00:49:17.220 --> 00:49:19.143
while they hunt their prey.

00:49:19.143 --> 00:49:21.726
(upbeat music)

00:49:37.710 --> 00:49:40.473
Aaron shares the recordings
with Sharon Swartz,

00:49:41.340 --> 00:49:43.743
a leading expert on bat flight.

00:49:46.800 --> 00:49:48.540
- [Sharon] That is beautiful.

00:49:48.540 --> 00:49:50.466
- [Aaron] Oh, we grabbed it.

00:49:50.466 --> 00:49:52.024
(Sharon chuckling)
Nice.

00:49:52.024 --> 00:49:54.570
(upbeat music)

00:49:54.570 --> 00:49:58.350
- [Narrator] Pirouettes, nose
dives, twists, and turns.

00:49:58.350 --> 00:50:01.920
The footage reveals the
bat's incredible agility.

00:50:01.920 --> 00:50:04.710
And these breathtaking
acrobatics are made possible

00:50:04.710 --> 00:50:08.043
by their ability to modify
the shape of their wings.

00:50:09.870 --> 00:50:14.130
- Bats have to have very nuanced control

00:50:14.130 --> 00:50:17.130
over all aspects of
their flight apparatus.

00:50:17.130 --> 00:50:19.830
We can see how bats use their wings

00:50:19.830 --> 00:50:23.850
to change those behaviors
in ways that really matter

00:50:23.850 --> 00:50:26.470
to the success of the
prey capture maneuver.

00:50:26.470 --> 00:50:29.053
(upbeat music)

00:50:34.770 --> 00:50:36.630
- [Narrator] Morphing is therefore key

00:50:36.630 --> 00:50:39.087
to the aerodynamic performance of bats.

00:50:39.087 --> 00:50:42.504
(upbeat music continues)

00:50:44.340 --> 00:50:46.320
Could this also be a way to innovate

00:50:46.320 --> 00:50:48.917
for the decarbonized planes of tomorrow?

00:50:48.917 --> 00:50:52.334
(upbeat music continues)

00:50:58.620 --> 00:51:01.260
- Bats have different
mechanisms in their flights

00:51:01.260 --> 00:51:04.700
that help reduce the
otherwise high cost of flight.

00:51:04.700 --> 00:51:08.310
So the extreme number of
articulations in the bat wing could

00:51:08.310 --> 00:51:10.947
contribute to reducing
the energy cost of flight.

00:51:10.947 --> 00:51:13.530
(upbeat music)

00:51:18.240 --> 00:51:20.910
- [Narrator] Brown University near Boston.

00:51:20.910 --> 00:51:24.120
Here biologists and
engineers have come together

00:51:24.120 --> 00:51:26.913
to better understand morphing in bats.

00:51:28.560 --> 00:51:31.080
Together they record
the wind tunnel flights

00:51:31.080 --> 00:51:32.583
of several specimens.

00:51:34.212 --> 00:51:35.430
- [Scientist 1] How was the flight?

00:51:35.430 --> 00:51:36.570
- [Scientist 2] I think
they're looking really great.

00:51:36.570 --> 00:51:38.970
I think we have a couple
of really great bats

00:51:38.970 --> 00:51:40.020
that are giving us what we need.

00:51:40.020 --> 00:51:40.980
So I think let's start

00:51:40.980 --> 00:51:43.383
with four meters per second next time.

00:51:43.383 --> 00:51:44.430
- Yep.
- And I think we'll be able

00:51:44.430 --> 00:51:46.529
to finish out the trials that way.

00:51:46.529 --> 00:51:47.919
- [Scientist 1] Sounds good.

00:51:47.919 --> 00:51:50.502
(upbeat music)

00:51:52.200 --> 00:51:54.450
- [Narrator] Data
collected, the scientists

00:51:54.450 --> 00:51:56.880
can now break down the
complex wing movements

00:51:56.880 --> 00:51:59.567
into simpler, fundamental movements.

00:51:59.567 --> 00:52:02.984
(upbeat music continues)

00:52:05.100 --> 00:52:09.090
- The way that we know bats
change the shape of their wing

00:52:09.090 --> 00:52:12.060
that could have special
importance aerodynamically

00:52:12.060 --> 00:52:13.380
is camber.

00:52:13.380 --> 00:52:16.470
And the camber is the curvature of a wing

00:52:16.470 --> 00:52:18.240
from the front to the back.

00:52:18.240 --> 00:52:21.390
And so, if we curve the
wing of this puppet,

00:52:21.390 --> 00:52:22.380
we can see that,

00:52:22.380 --> 00:52:24.630
if we bring the front edge down,

00:52:24.630 --> 00:52:28.530
and the back edge down so that
it's lifted up in the middle,

00:52:28.530 --> 00:52:30.360
we have kind of an arc.

00:52:30.360 --> 00:52:35.360
And that arc of the wing then
gives the wing extra lift.

00:52:35.850 --> 00:52:38.730
So, if we take the wing

00:52:38.730 --> 00:52:42.390
and put it in some air as a flat surface,

00:52:42.390 --> 00:52:44.520
it'll generate a certain amount of lift.

00:52:44.520 --> 00:52:46.980
And if we take exactly the same wing

00:52:46.980 --> 00:52:50.820
and give it camber, the
amount of lift will increase

00:52:50.820 --> 00:52:53.588
just from changing the Camber,

00:52:53.588 --> 00:52:55.710
(upbeat music)

00:52:55.710 --> 00:52:57.180
- [Narrator] Physicist Kenny Brewer

00:52:57.180 --> 00:52:59.580
and roboticist, Zhao Cho Phan,

00:52:59.580 --> 00:53:01.170
dream of designing a robot

00:53:01.170 --> 00:53:03.556
capable of reproducing this movement.

00:53:03.556 --> 00:53:07.290
(upbeat music continues)

00:53:07.290 --> 00:53:08.550
To achieve this goal,

00:53:08.550 --> 00:53:11.130
they must first adopt
a mathematical approach

00:53:11.130 --> 00:53:13.260
in order to better understand the role

00:53:13.260 --> 00:53:15.993
that camber plays in the flight of bats.

00:53:17.757 --> 00:53:20.319
- All right, so what do we have?

00:53:20.319 --> 00:53:25.200
- Let's see.
(upbeat music)

00:53:25.200 --> 00:53:28.230
- [Narrator] From observing
the bats in the wind tunnel,

00:53:28.230 --> 00:53:31.230
Zhao Cho has developed a digital model.

00:53:31.230 --> 00:53:34.647
(upbeat music continues)

00:53:37.350 --> 00:53:39.600
It simulates variations in camber,

00:53:39.600 --> 00:53:41.553
depending on the speed of flight.

00:53:42.870 --> 00:53:44.610
The quicker the bat flies,

00:53:44.610 --> 00:53:47.103
the less camber there is in its wings.

00:53:49.620 --> 00:53:51.660
- It reduces the aerodynamic drag

00:53:51.660 --> 00:53:52.920
as you fly faster and faster.

00:53:52.920 --> 00:53:54.697
- Yeah, 'cause the weight is the same.

00:53:54.697 --> 00:53:56.790
- Yeah.
- So, as you go faster,

00:53:56.790 --> 00:53:58.593
it needs less coefficient of lift.

00:53:58.593 --> 00:53:59.480
- Yes. Yes.
- And so,

00:53:59.480 --> 00:54:01.500
it reduces the camber.
- Yes.

00:54:01.500 --> 00:54:03.600
- And that allows it to
maintain weight support,

00:54:03.600 --> 00:54:04.590
but at lower power.

00:54:04.590 --> 00:54:07.083
- Exactly. That's a very smart strategy.

00:54:07.920 --> 00:54:10.560
- [Narrator] Zhao Cho's
latest calculations show

00:54:10.560 --> 00:54:14.730
that continuous camber control
would enable a robot bat

00:54:14.730 --> 00:54:17.493
to be up to 18% more efficient.

00:54:19.260 --> 00:54:21.930
So the research by
engineers and biologists

00:54:21.930 --> 00:54:24.180
at Brown University proves

00:54:24.180 --> 00:54:27.720
that machines inspired by the
flexibility of flying animals

00:54:27.720 --> 00:54:29.648
can use less energy.

00:54:29.648 --> 00:54:32.231
(upbeat music)

00:54:35.790 --> 00:54:37.110
All across the world,

00:54:37.110 --> 00:54:39.930
more and more audacious
aeronautical projects

00:54:39.930 --> 00:54:41.368
are on the increase.

00:54:41.368 --> 00:54:45.523
(upbeat music continues)

00:54:45.523 --> 00:54:48.459
(airplane flying)

00:54:48.459 --> 00:54:52.170
(upbeat music continues)

00:54:52.170 --> 00:54:54.480
Integrating morphing into these machines

00:54:54.480 --> 00:54:56.793
is considerable energy savings.

00:55:02.460 --> 00:55:06.060
In Toulouse, Airbus
has already carried out

00:55:06.060 --> 00:55:08.700
flight tests using a revolutionary,

00:55:08.700 --> 00:55:11.610
articulated and bendable wing,

00:55:11.610 --> 00:55:15.753
an aerofoil that can fold
to reduce energy waste.

00:55:18.187 --> 00:55:22.270
(speaking in a foreign language)

00:55:26.520 --> 00:55:29.640
In Turin, the Italian company, Leonardo,

00:55:29.640 --> 00:55:32.250
has also integrated morphing technology

00:55:32.250 --> 00:55:35.105
into a high performance,
transport aircraft.

00:55:35.105 --> 00:55:38.522
(upbeat music continues)

00:55:41.100 --> 00:55:42.330
In the near future,

00:55:42.330 --> 00:55:44.370
other superpowers from flying animals

00:55:44.370 --> 00:55:46.767
will change the face of aeronautics.

00:55:46.767 --> 00:55:49.680
(upbeat music)

00:55:49.680 --> 00:55:53.100
In the United States, NASA
is working on a flying wing

00:55:53.100 --> 00:55:54.750
that works like a Pterosaur.

00:55:54.750 --> 00:55:56.670
This device could be the first glider

00:55:56.670 --> 00:55:59.460
to fly over the planet Mars.

00:55:59.460 --> 00:56:03.270
Bio-inspired techniques first
noted in Leonardo's work

00:56:03.270 --> 00:56:05.670
are thriving like never before.

00:56:05.670 --> 00:56:07.020
- Of course, all the discoveries

00:56:07.020 --> 00:56:09.630
that we're making today are built off

00:56:09.630 --> 00:56:11.640
of the foundation of knowledge

00:56:11.640 --> 00:56:14.670
that's been generated
from hundreds of years

00:56:14.670 --> 00:56:17.043
going all the way back to DaVinci's time.

00:56:18.900 --> 00:56:21.390
- [Narrator] From Leonardo
DaVinci's ornathopters

00:56:21.390 --> 00:56:23.370
to the airplanes of tomorrow,

00:56:23.370 --> 00:56:27.720
flying animals have been and
always will be at our sides

00:56:27.720 --> 00:56:30.835
to help us accomplish our greatest dream.

00:56:30.835 --> 00:56:33.418
(upbeat music)

00:56:39.420 --> 00:56:42.375
- Would we ever have taken to the skies,

00:56:42.375 --> 00:56:44.430
if there weren't birds, and bats,

00:56:44.430 --> 00:56:47.100
and insects that we could watch?

00:56:47.100 --> 00:56:48.870
I'm not so sure.

00:56:48.870 --> 00:56:49.860
There are so many things,

00:56:49.860 --> 00:56:54.860
which seem theoretically challenging,

00:56:55.470 --> 00:56:58.125
but, you know, nature finds a way.

00:56:58.125 --> 00:57:00.708
(upbeat music)