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The natural world is beautiful,
but complex.
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The skies dance with colour.
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Shapes form...
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00:00:19,707 --> 00:00:21,047
..and disappear.
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00:00:25,726 --> 00:00:30,886
But this seemingly infinite complexity is
just a shadow of something deeper.
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00:00:31,326 --> 00:00:33,305
The underlying laws.
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The laws of nature.
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The world is beautiful to look at, but
it's even more beautiful to understand.
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A regular day in the snow.
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But if you look carefully, there's
something deeper.
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Everyone...
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..is perfect, pretty much.
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Looks like they've been cut out of thin
paper.
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I got one!
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00:01:51,993 --> 00:01:54,993
Snowflakes are complex, intricate things.
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But they're all different, but there's
something similar about them.
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They are beautiful.
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00:02:01,432 --> 00:02:05,331
But there is also, I think, a deeper
beauty, and that beauty is in an idea.
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00:02:06,211 --> 00:02:07,651
The idea is that...
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..all the similarities and difference,
the structure of snowflakes, can be
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explained using a few simple laws of
nature.
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00:02:16,369 --> 00:02:19,855
And that idea goes to the
very heart of science, because
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those laws themselves are
beautiful and they're universal.
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They can explain so many things,
from snowflakes to stars.
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How do snowflakes form?
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00:02:36,646 --> 00:02:40,646
Why are they all different, and yet
tantalisingly similar?
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00:02:45,035 --> 00:02:49,014
These are questions that can be asked
about any naturally occurring structure.
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00:02:52,774 --> 00:02:55,293
Why are beehives regular hexagons?
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00:02:56,053 --> 00:02:57,693
Why do icebergs float?
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00:02:58,473 --> 00:03:00,093
Why are planets spherical?
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And what's this got to do with free diving
grannies?
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The answers allow us to glimpse the
underlying laws of nature that shape them.
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This is why, when you look at a
snowflake...
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..you're peering beyond the everyday world,
at the deep structure of nature itself.
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The universe in a snowflake.
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Wow, I can see a star.
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It really looks like a snow crystal stuck
in a bubble.
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00:03:53,104 --> 00:03:56,644
There's a shape that appears at all scales
in the universe.
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00:04:01,963 --> 00:04:05,722
Seen from space, the Earth is a
near-perfect sphere...
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00:04:09,382 --> 00:04:12,561
..sculpted by one of the fundamental
forces of nature.
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00:04:19,920 --> 00:04:21,220
Carla, it's your turn now.
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I want, I want, I want...
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What's possible?
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Carla and her friends
are about to pit themselves
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against the force
that's shaped our planet.
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Because it's the first time that I've gone
to a hole.
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And when it's nine o'clock in the morning,
everyone is going to jump to the surface
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Well, it's very exciting.
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You get very nervous.
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00:05:21,371 --> 00:05:23,230
Very nervous for them,
very nervous for everything to
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00:05:23,231 --> 00:05:25,430
go well, for them not to
fall, for them not to get hurt.
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What you feel is a beastly emotion,
because you get goose bumps and sometimes
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you are about to cry before starting to
build castles.
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00:05:45,887 --> 00:05:50,766
These children are going into battle,
with gravity.
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00:06:05,084 --> 00:06:11,923
Towns from across Catalonia have gathered
to enter into a fierce competition,
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to build a human capital.
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00:06:16,682 --> 00:06:18,682
A tower as high as possible.
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00:06:26,841 --> 00:06:29,994
Mum and dad are here
with their daughters, Mariona
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00:06:29,995 --> 00:06:33,041
and Carla, to represent
the town of Villafranca.
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00:06:36,979 --> 00:06:42,238
People of all ages take part, but it's the
lightest members of the team, children as
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young as five, who ascend daringly to the
summit.
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There is a lot of nerves, because there
are many people.
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The family put their trust in the most
experienced members of the team,
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like David Miret.
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Depression of the stage, right?
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In addition, the Plaza de Braus has this
circular shape, the sound is very loud and
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it is a wave, a wave.
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00:07:15,433 --> 00:07:19,653
From the outside, it may seem that we are
a group of people, that we climb up and
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that we pile up in an anarchic way,
totally, without any rigor.
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The first one is the last one!
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00:07:27,011 --> 00:07:29,591
But no, not all structures have...
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00:07:34,030 --> 00:07:36,890
David feels the weight of everyone above
him.
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His gravity pulls them down to the ground.
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00:07:46,708 --> 00:07:50,768
And he knows the secret to defying gravity
is geometry.
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They are symmetrical below, they have
their own line, they create concentric
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00:07:56,628 --> 00:07:59,946
lines towards that point, so that the
forces go concentrically.
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To support David, and eventually the kids,
the rest of the town all pushed inwards,
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with equal force in all directions,
buttressing the tower from all sides.
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00:08:18,743 --> 00:08:21,783
And this results in the emergence of a
symmetrical shape.
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A circle.
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00:08:24,623 --> 00:08:27,222
No other shape gives the tower such
strength.
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00:08:39,340 --> 00:08:41,960
But gravity is unforgiving.
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00:09:15,205 --> 00:09:19,264
And that's a worry if your child is
climbing to the top.
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00:09:21,504 --> 00:09:24,287
When Carla and Mariona
climb up the castle, I have
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00:09:24,288 --> 00:09:26,643
to follow the castle from
the bottom to the top.
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I can't be without looking at the castle.
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When I climb up the castle, I try not to
fall.
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00:10:53,400 --> 00:10:57,139
It's clear that the force of gravity is
unrelenting.
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00:11:01,778 --> 00:11:06,898
The collapsing towers are shadows of the
process that shaped our planet.
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These people aren't just falling down.
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00:11:14,117 --> 00:11:15,517
They're falling towards the ground.
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00:11:17,376 --> 00:11:20,295
They're falling towards the centre of the
Earth.
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00:11:21,415 --> 00:11:23,455
And the Earth's gravity pulls everything
down.
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From people to snowflakes.
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To the very rock that the Earth is made
of.
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00:11:36,733 --> 00:11:39,593
And this is ultimately why the Earth is
spherical.
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00:11:41,932 --> 00:11:45,352
So why does gravity sculpt things into
spheres?
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Well, the first thing to say is that it
doesn't, necessarily.
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If I pick up a snowball...
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it's not spherical.
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Kind of an irregular shape.
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But if I apply pressure to it...
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and squash it evenly in all directions...
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then I can turn that into a sphere.
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And that is what's happening with gravity.
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As I start adding mass to it... that
gravitational pull becomes bigger.
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00:12:19,916 --> 00:12:22,586
So I'll get to a point where this
snowball...
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if I kept adding mass to it...
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would be so massive...
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that the gravitational pull on its surface
would be so strong...
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that it would start to squash the material
out of which it's made.
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In this case, snow.
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Or in the case of a planet or moon,
the rock.
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That pressure exerts on the
surface... equally in all directions.
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Because gravity works equally in all
directions.
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Now, you could ask the question...
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how much matter do I need for gravity to
get strong enough...
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to start overcoming the strength of
rock...
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00:12:58,010 --> 00:12:59,500
and sculpting things into spheres?
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Well, that minimum size has got a name.
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It's a brilliant name.
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It's called the potato radius.
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And you see why.
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Because things that are too small...
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for gravity to be strong enough to sculpt
them...
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look like misshapen potatoes.
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00:13:18,297 --> 00:13:21,307
The great thing is... you
don't even need to imagine it.
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You can calculate it.
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00:13:23,896 --> 00:13:24,896
I did that this morning.
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00:13:25,126 --> 00:13:28,426
And I got an answer... just roughly
between 100 and 200 kilometres.
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00:13:29,406 --> 00:13:32,325
The brilliant thing... the
most beautiful thing...
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is if you look up into space...
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and look at the moons of Mars and Saturn
and Jupiter...
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00:13:37,045 --> 00:13:39,124
and objects out there in the solar
system...
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00:13:39,474 --> 00:13:41,864
you will find that, roughly speaking...
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if their radius is bigger...
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than about 200 kilometres...
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they're beautiful spheres.
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00:13:46,803 --> 00:13:49,802
And if the radius is less...
than about 200 kilometres...
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they look more like misshapen potatoes.
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00:13:52,822 --> 00:13:54,682
So you can calculate it.
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00:13:59,396 --> 00:14:00,451
If you're small...
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spheres don't come easily.
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00:14:05,690 --> 00:14:09,209
Even asteroids or moons...
don't quite manage it.
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00:14:09,569 --> 00:14:12,689
A potato shape... might
be as close as you can get.
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00:14:17,938 --> 00:14:21,458
But when you're the size of a
planet... spheres come naturally.
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00:14:29,856 --> 00:14:34,236
Four and a half billion years
ago... rocks circling the Sun...
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began sticking together...
until they had sufficient mass...
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00:14:37,976 --> 00:14:42,494
for gravity to really get to
work... turning potato shapes...
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00:14:42,495 --> 00:14:46,574
into one very important
sphere... suspended in space.
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00:14:53,063 --> 00:14:56,702
A universal law...
sculpted the familiar...
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elegant, symmetrical
shape... of our planet.
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00:15:06,861 --> 00:15:12,340
But closer to the surface... it's
littered... with endless shapes and forms.
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And in every one of these...
naturally occurring structures...
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there are simple underlying
laws... waiting to be glimpsed.
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Here in the Himalayas...
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there's a shape... that's a shadow...
of a fundamental mathematical law.
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It's guarded by the Himalayan honey bee...
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the largest species of
honey bee... on the planet.
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And collecting honey... from under
their watchful... compound eyes...
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is one of the most dangerous
jobs... you could imagine.
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But that's nothing...
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for the young villagers.
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00:16:19,209 --> 00:16:22,010
Today... it's the first time...
for one of the young villagers.
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00:16:22,524 --> 00:16:24,609
Min and his nephew Herah...
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will be the ones leading the
hunt... for the precious honey.
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00:16:27,988 --> 00:16:30,608
It's prized... for its
medicinal properties...
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and sells for a high price.
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The local culture...
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protects the whole
place... by its magic.
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Be careful...
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when you are walking
on... these roads...
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Hidden beneath the
seething mass of bodies sits
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00:16:50,107 --> 00:16:53,465
a network of exquisitely
engineered hexagons.
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00:16:57,833 --> 00:17:01,560
The bees appear to be
master builders, performing
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00:17:01,561 --> 00:17:04,692
structural calculations
with architectural precision.
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The bees benefit from a
hidden mathematical law that
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explains why they build
hexagons to store their honey.
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00:17:26,884 --> 00:17:29,455
And twice a year, the
Gurung people head into
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00:17:29,555 --> 00:17:32,868
the mountains to
exploit the bees' secret.
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00:17:36,458 --> 00:17:42,078
Because it's Hira's first time, this
trip will be particularly challenging.
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If you want to eat honey, you have to dig
a hole.
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This is the new honey that I learned from
Niravani.
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This is Hira's honey.
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I don't know if it will work or not.
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00:18:04,613 --> 00:18:06,133
Uncle, let's start from the beginning.
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Hey,
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let's start from the beginning.
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Hey, take it.
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00:18:26,120 --> 00:18:31,120
The bees make their hives as inaccessible
as possible to protect them from predators.
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00:19:02,614 --> 00:19:08,126
The hives the bees are
defending contain a vivid,
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visible solution to a deep
mathematical problem.
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And a very practical one.
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00:19:15,517 --> 00:19:19,912
They need to store honey to sustain their
colony through the long winter months.
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00:19:21,411 --> 00:19:22,911
They build their hives out of wax.
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00:19:25,051 --> 00:19:28,574
But for every gram of
wax a bee produces, it will
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00:19:28,624 --> 00:19:31,680
have to consume more
than six grams of honey.
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00:19:34,779 --> 00:19:39,649
So they benefit from building efficiently,
using as little wax as possible.
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00:19:58,756 --> 00:20:01,575
In the beginning, I was a little scared of
primers.
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00:20:26,151 --> 00:20:27,151
Each
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sting is like a hypodermic needle.
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00:20:38,829 --> 00:20:40,889
After the bees sting, they die.
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The ultimate sacrifice.
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To guard the hexagons.
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And the honey they hold.
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00:21:02,056 --> 00:21:03,836
At first, I was a little scared.
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00:21:05,075 --> 00:21:09,475
But when I got to the bank, I realized
that it's okay.
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00:21:09,935 --> 00:21:11,194
I have my own mind.
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00:21:47,329 --> 00:21:53,168
Before I started learning, I was a little
scared.
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00:21:53,848 --> 00:21:54,848
I was afraid.
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00:21:55,008 --> 00:21:56,008
Maybe.
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00:21:56,827 --> 00:21:58,627
But it is a good thing, always.
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When I see the honey, I start working on
it.
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00:22:10,005 --> 00:22:14,385
For Hiro, this is all about keeping the
Gurung tradition of honey hunting alive.
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00:22:17,224 --> 00:22:20,644
When the hexagon is at the heart of it
all.
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00:22:21,344 --> 00:22:29,142
I just want the honey to keep on growing.
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00:22:41,501 --> 00:22:43,470
How do bees build hexagonal honeycombs?
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00:22:46,115 --> 00:22:48,689
Well, that is, in fact, a very good
question.
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00:22:48,829 --> 00:22:50,349
It's actually a mathematical question.
220
00:22:53,354 --> 00:22:57,747
The problem is, how do
I divide up a volume into
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00:22:57,748 --> 00:23:01,487
shapes of equal size using
the minimum amount of stuff?
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00:23:02,847 --> 00:23:04,787
Now, why does that matter to a bee?
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00:23:05,317 --> 00:23:09,586
Because that stuff is wax, and wax is
extremely valuable to the bees.
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00:23:09,786 --> 00:23:13,066
So, what shape should it be?
225
00:23:13,656 --> 00:23:16,865
Should it be squares, or should it be
triangles?
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00:23:17,295 --> 00:23:20,065
You can see it can't be circles,
because circles, when you pack them
227
00:23:20,066 --> 00:23:22,364
together, leave gaps, so they're not very
efficient.
228
00:23:23,264 --> 00:23:26,744
Or could it be that hexagons are the most
efficient?
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00:23:27,703 --> 00:23:32,983
Well, that is actually a simple-sounding
question with a very complicated answer.
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00:23:33,083 --> 00:23:34,982
It's one of the oldest questions in
mathematics.
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00:23:35,952 --> 00:23:36,992
It's got a name, actually.
232
00:23:37,212 --> 00:23:38,692
It's called the honeycomb conjecture.
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00:23:39,042 --> 00:23:42,081
Mathematicians say, that the bees have
worked on it for thousands and thousands
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00:23:42,082 --> 00:23:47,680
of years, and it's only recently that the
honeycomb conjecture was proved.
235
00:23:49,030 --> 00:23:50,030
Here's one of the proofs.
236
00:23:51,340 --> 00:23:52,480
Huge paper.
237
00:23:53,599 --> 00:23:56,499
Pages and pages of complex mathematics.
238
00:23:57,774 --> 00:24:01,318
And it turns out that the hexagon is the
most efficient shape.
239
00:24:02,083 --> 00:24:07,037
The bees knew what human mathematicians
didn't know for thousands of years.
240
00:24:07,592 --> 00:24:09,557
Actually, I'm using know in quite a way.
241
00:24:09,558 --> 00:24:10,793
There's quite a loose sense there.
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00:24:10,817 --> 00:24:13,623
There's still a great
deal of debate amongst
243
00:24:13,624 --> 00:24:16,497
biologists as to how
the bees actually do it.
244
00:24:17,046 --> 00:24:23,375
Do they build hexagons from scratch using
some kind of instinctive behaviour?
245
00:24:24,185 --> 00:24:28,494
Or do they in fact build a simpler shape,
perhaps circles, and then because the wax
246
00:24:28,644 --> 00:24:31,865
heats up, it can deform,
and the laws of physics
247
00:24:31,866 --> 00:24:34,573
themselves change the
circles into hexagons?
248
00:24:35,083 --> 00:24:36,413
That's still not agreed upon.
249
00:24:36,414 --> 00:24:40,361
But what is agreed upon
by the mathematicians and
250
00:24:40,362 --> 00:24:43,412
the bees is the hexagon
is the most efficient shape.
251
00:24:44,062 --> 00:24:45,741
That just shows you it's a beautiful
thing.
252
00:24:46,021 --> 00:24:48,931
Mathematics is the universal language.
253
00:24:49,291 --> 00:24:54,230
And when you look at a perfect honeycomb,
you see a shadow of that language,
254
00:24:54,430 --> 00:24:58,569
of mathematics made real by bees.
255
00:25:05,178 --> 00:25:07,918
Perfect shapes reveal simple laws.
256
00:25:13,437 --> 00:25:17,077
Whether it's spherical planets sculpted by
gravity,
257
00:25:21,126 --> 00:25:23,725
pulling us to the centre of the Earth...
258
00:25:27,845 --> 00:25:32,764
..or the mathematically refined efficiency
of hexagonal honeycombs...
259
00:25:36,324 --> 00:25:39,563
..simple laws underpin the shapes we can
see.
260
00:25:40,668 --> 00:25:42,123
And they're universal.
261
00:25:45,502 --> 00:25:51,001
But the action of these simple laws seems
at odds with the complex shapes of life.
262
00:26:04,099 --> 00:26:09,738
These shallow springs are home to one of
nature's seemingly less elegant shapes...
263
00:26:18,507 --> 00:26:19,507
..the manatee.
264
00:26:20,877 --> 00:26:24,826
Like all marine animals, they're free from
the effects of gravity.
265
00:26:25,641 --> 00:26:27,946
No need for strong bones to support their
weight.
266
00:26:30,105 --> 00:26:32,865
But they don't have complete freedom from
the laws of physics.
267
00:26:33,410 --> 00:26:36,164
Several manatees are hunting some mothers
and cats.
268
00:26:36,304 --> 00:26:37,304
There they are.
269
00:26:38,024 --> 00:26:39,024
It's winter.
270
00:26:39,184 --> 00:26:43,063
And if the water temperature here drops
below 20 degrees...
271
00:26:43,064 --> 00:26:44,943
Do you think the temperature's Friday
morning?
272
00:26:45,523 --> 00:26:47,643
..for the manatee, it's deadly.
273
00:26:48,607 --> 00:26:51,922
Very dangerous in terms of warmer and
hotter environments.
274
00:26:53,762 --> 00:26:56,961
Manatees, like this female, are
vegetarians.
275
00:26:59,311 --> 00:27:02,660
Basically, she's a ten-foot-long aquatic
cow with no legs.
276
00:27:03,650 --> 00:27:05,962
To stay warm, she
has to consume up to 50
277
00:27:05,963 --> 00:27:09,780
kilograms of leaves
and sea grass every day.
278
00:27:10,789 --> 00:27:13,119
And the females here are eating for
others, too.
279
00:27:14,388 --> 00:27:16,498
This one is suckling two young calves.
280
00:27:16,998 --> 00:27:19,538
And the weather is only getting colder.
281
00:27:22,337 --> 00:27:23,337
Lemon?
282
00:27:24,747 --> 00:27:25,747
On the roof?
283
00:27:26,337 --> 00:27:27,336
No.
284
00:27:29,266 --> 00:27:30,706
Looking good.
285
00:27:36,085 --> 00:27:37,085
There's Doug.
286
00:27:37,535 --> 00:27:38,645
Doug likes it up here now.
287
00:27:39,790 --> 00:27:42,347
Researcher Wayne Hartley
is doing this morning's
288
00:27:42,348 --> 00:27:45,345
head count, part of
the manatee census.
289
00:27:49,483 --> 00:27:52,023
It's a special thing to come to work.
290
00:27:52,763 --> 00:27:56,762
You come down in the morning and it's
quiet.
291
00:27:57,832 --> 00:27:59,661
The steam's coming off the water.
292
00:28:04,791 --> 00:28:07,150
You can hear the manatees out there,
breathing.
293
00:28:07,520 --> 00:28:08,690
It's just whoosh.
294
00:28:11,340 --> 00:28:12,989
And they are so peaceful.
295
00:28:13,189 --> 00:28:14,509
They are so calm.
296
00:28:16,669 --> 00:28:19,918
Just watching manatees,
it's got to be good for your
297
00:28:19,919 --> 00:28:22,888
blood pressure or anything
else that may ail you.
298
00:28:33,476 --> 00:28:37,576
Biologist Amy Tegg is working with Wayne
to do a health check on the families.
299
00:28:40,055 --> 00:28:43,075
Well, he's just sort of hanging around,
checking things out.
300
00:28:43,076 --> 00:28:46,954
Manatees are very docile, gentle
creatures.
301
00:28:48,014 --> 00:28:49,174
But they are very curious.
302
00:28:49,944 --> 00:28:53,213
Anything new in their environment,
they often like to come check out.
303
00:28:53,823 --> 00:28:56,633
So he's probably just checking me out.
304
00:28:57,433 --> 00:28:59,172
Yeah, he's just chewing on my flipper.
305
00:29:00,742 --> 00:29:02,472
It's got 23.5 degrees Celsius.
306
00:29:03,852 --> 00:29:08,051
Manatee families are drawn in from colder
waters because this is a hot spring.
307
00:29:09,341 --> 00:29:11,130
And some make it just in time.
308
00:29:11,131 --> 00:29:14,110
He is severely cold-stressed.
309
00:29:16,160 --> 00:29:17,809
With the cold stress, they don't eat.
310
00:29:19,429 --> 00:29:21,029
Their immune system shuts down.
311
00:29:22,029 --> 00:29:24,768
They're here to keep themselves alive in
the winter.
312
00:29:24,948 --> 00:29:28,288
They really require warm water.
313
00:29:32,597 --> 00:29:36,976
It might look like these animals keep warm
using blubber, like seals.
314
00:29:38,076 --> 00:29:39,396
But they're not fat.
315
00:29:40,266 --> 00:29:41,266
They're round.
316
00:29:42,471 --> 00:29:46,535
In terms of pure physics, the best way to
stay warm is to be a sphere.
317
00:29:51,154 --> 00:29:55,474
It has the smallest surface area-to-volume
ratio of any shape.
318
00:29:56,174 --> 00:29:58,773
Less area for heat to escape from.
319
00:30:00,173 --> 00:30:03,334
A beautiful example
of a naturally occurring
320
00:30:03,335 --> 00:30:06,432
shape, reflecting a
deeper mathematical law.
321
00:30:07,752 --> 00:30:11,131
The manatee could well be the most
spherical mammal on Earth.
322
00:30:11,971 --> 00:30:13,551
What a wonderful thing to be.
323
00:30:19,540 --> 00:30:20,140
The manatee is a manatee.
324
00:30:20,141 --> 00:30:21,221
Sorry, their breath stinks.
325
00:30:22,379 --> 00:30:25,119
To me, it smells like the inside of a hot
truck tire.
326
00:30:30,358 --> 00:30:32,778
But of course, they're not perfect
spheres.
327
00:30:34,673 --> 00:30:38,377
There are many other competing factors
that determine their shape.
328
00:30:39,017 --> 00:30:45,276
Like all animals, they have to
live, breathe, eat... and move.
329
00:30:48,855 --> 00:30:50,835
The manatee's natural habitat is
shrinking.
330
00:30:51,665 --> 00:30:53,755
And they need to find warmth elsewhere.
331
00:30:57,774 --> 00:31:01,993
This power station helps provide energy
for around nine million people.
332
00:31:02,833 --> 00:31:06,413
And in the process, warms
the water that keeps over
333
00:31:06,414 --> 00:31:09,212
half of Florida's manatees
alive through the winter.
334
00:31:13,642 --> 00:31:20,121
The same families that Wayne and Amy study
can end up here, over 300 kilometres away.
335
00:31:21,340 --> 00:31:24,880
Where their mothers and calves can hold on
to as much heat as possible.
336
00:31:26,140 --> 00:31:27,879
Because of their round bodies.
337
00:31:30,519 --> 00:31:35,738
To a physicist, the perfect shape for a
manatee would be a symmetrical sphere.
338
00:31:36,943 --> 00:31:38,558
But biology complicates things.
339
00:31:40,617 --> 00:31:44,817
Manatees can't just bob around waiting for
food or warmth to come to them.
340
00:31:45,997 --> 00:31:48,696
They need fins and a tail to move around.
341
00:31:50,656 --> 00:31:53,975
Whether that's to a hot spring,
or to a power station.
342
00:32:05,984 --> 00:32:10,363
The forces of nature sculpt and restrict
the shapes of all things.
343
00:32:10,663 --> 00:32:14,982
The inanimate, like pebbles or rocks or
cliffs.
344
00:32:15,662 --> 00:32:16,942
Or living things.
345
00:32:19,601 --> 00:32:23,601
But of course, basic physics is not the
only force shaping life.
346
00:32:28,140 --> 00:32:33,499
Evolution by natural selection moulds
living things over time in response to
347
00:32:33,500 --> 00:32:36,899
their environment and their interaction
with other life forms.
348
00:32:41,138 --> 00:32:43,838
And it's had billions of years to do it.
349
00:32:46,527 --> 00:32:48,577
So, you can't understand the shapes.
350
00:32:49,027 --> 00:32:50,113
The shapes of living things.
351
00:32:50,137 --> 00:32:52,696
Without understanding their evolutionary
history.
352
00:33:16,593 --> 00:33:17,592
We're
353
00:33:25,481 --> 00:33:28,021
all the product of our experiences.
354
00:33:28,501 --> 00:33:29,861
Our history.
355
00:33:30,021 --> 00:33:31,120
Our culture.
356
00:33:31,770 --> 00:33:34,340
Our lives make an indelible impression.
357
00:33:35,700 --> 00:33:36,740
And make us all different.
358
00:33:42,389 --> 00:33:44,148
But we are also all similar.
359
00:33:45,448 --> 00:33:47,088
Not just to each other as human beings.
360
00:33:47,568 --> 00:33:50,127
But to countless other animals on Earth.
361
00:33:51,477 --> 00:33:53,007
We are obviously related.
362
00:33:57,816 --> 00:33:58,816
Most obviously.
363
00:33:59,491 --> 00:34:01,686
Through the symmetry of our bodies.
364
00:34:16,903 --> 00:34:17,903
I'm Kim Sun-duk.
365
00:34:18,628 --> 00:34:19,628
I'm 73.
366
00:34:23,022 --> 00:34:28,162
Mrs. Choi and Ms. Kim, the Henyo,
are women of the sea.
367
00:34:28,362 --> 00:34:30,901
They've grown up collecting seafood along
the shores.
368
00:34:32,641 --> 00:34:34,041
But they still do.
369
00:34:47,089 --> 00:34:49,648
The haenyeo are part of a dying tradition.
370
00:34:50,188 --> 00:34:52,528
Not many youngsters are interested in one.
371
00:34:53,988 --> 00:34:57,667
It's hard work, especially if you're in
your seventies.
372
00:35:26,133 --> 00:35:29,692
Right now, the women are catching conch,
or sea snails.
373
00:35:33,112 --> 00:35:37,111
It's a crucial time of year, when they
have a chance to make the most money.
374
00:35:49,969 --> 00:35:54,788
The tradition of freediving for food is
part of these women's cultural history,
375
00:35:55,223 --> 00:36:01,287
but the details of the human form itself,
in particular its symmetry that allows
376
00:36:01,288 --> 00:36:05,847
them to dive, swim and hunt, is part of
their evolutionary history.
377
00:36:18,485 --> 00:36:20,844
For Mrs Choi, and Miss Kim, this is all
about the search for food.
378
00:36:20,864 --> 00:36:27,563
Calming sensation
379
00:36:45,370 --> 00:36:49,510
For Mrs Choi and Miss Kim, this is all
about the search for food.
380
00:36:53,619 --> 00:36:57,219
And that's where the symmetrical structure
of their bodies comes in.
381
00:36:57,794 --> 00:37:02,838
A blueprint that started out here in the
oceans, hundreds of millions of years ago.
382
00:37:06,847 --> 00:37:09,327
Very few animals have steered clear of it.
383
00:37:32,973 --> 00:37:36,693
Life is, and always has been, a
competition.
384
00:37:37,467 --> 00:37:40,524
In a free-floating
world, life grew to adopt
385
00:37:40,525 --> 00:37:43,852
different types of symmetry
to get what it needed.
386
00:37:46,411 --> 00:37:50,110
Some animals became
round, or radially symmetric,
387
00:37:50,111 --> 00:37:53,630
organising their sensory
organs around a central axis.
388
00:37:54,870 --> 00:37:59,069
Rather than chasing down food,
they waited for food to come to them.
389
00:38:01,169 --> 00:38:06,128
But in order to really go after prey,
you need to leave that strategy behind.
390
00:38:09,657 --> 00:38:12,097
You need to be divided down the middle.
391
00:38:13,017 --> 00:38:14,257
That gives you two sides.
392
00:38:15,257 --> 00:38:16,256
A bilateral symmetry.
393
00:38:16,576 --> 00:38:19,136
Basically, you have a left and a right.
394
00:38:22,845 --> 00:38:27,525
And you can build on this plan,
with arms to grab and search.
395
00:38:27,745 --> 00:38:29,724
And a head, and a tail.
396
00:38:31,144 --> 00:38:36,143
All this means you can orientate yourself,
and really target your prey.
397
00:38:44,322 --> 00:38:49,201
This body plan has been selected for over
hundreds of millions of years.
398
00:38:50,061 --> 00:38:52,241
It confers a survival advantage.
399
00:38:53,641 --> 00:38:58,460
And it turns out that all animals with
brains are bilaterally symmetrical.
400
00:39:03,819 --> 00:39:06,580
Bilateral symmetry
provided the agility that
401
00:39:06,592 --> 00:39:09,118
drove a spiral of
cunning and ingenuity.
402
00:39:09,119 --> 00:39:10,624
And the ability to catch fast predators.
403
00:39:10,648 --> 00:39:12,398
And skittish, speedy prey.
404
00:39:13,738 --> 00:39:15,937
It's been a long time since we've had such
strong waves.
405
00:39:23,916 --> 00:39:25,376
I caught a lot today.
406
00:39:25,736 --> 00:39:29,575
When I catch a lot, I feel good.
407
00:39:29,835 --> 00:39:30,871
I feel like I'm going to fly.
408
00:39:30,895 --> 00:39:33,295
But if I can't catch this, I feel bad.
409
00:39:33,754 --> 00:39:34,890
I feel like I'm going to die.
410
00:39:34,914 --> 00:39:35,914
I'm going to die.
411
00:39:36,194 --> 00:39:42,903
I'm going to die.
412
00:39:42,904 --> 00:39:43,123
I'm going to die.
413
00:39:43,124 --> 00:39:46,762
The beautiful symmetry of the human body,
which we all take for granted,
414
00:39:48,022 --> 00:39:51,342
is the product of a sweeping, majestic
story.
415
00:39:53,201 --> 00:39:56,201
Stretching back to some of the earliest
life on Earth.
416
00:40:06,229 --> 00:40:11,669
So we can understand the symmetry of
organisms by understanding their history.
417
00:40:14,268 --> 00:40:19,607
You're essentially seeing the results of
evolution by natural selection over
418
00:40:19,608 --> 00:40:23,427
hundreds of millions, even billions of
years.
419
00:40:27,496 --> 00:40:32,565
But how do you understand the structure
and symmetry of a snowflake?
420
00:40:33,175 --> 00:40:35,265
There's no natural selection here.
421
00:40:35,845 --> 00:40:39,584
There's no DNA to record and reproduce
information.
422
00:40:39,585 --> 00:40:45,503
These things arise spontaneously from
basic laws of physics.
423
00:40:47,463 --> 00:40:48,463
Bingo!
424
00:40:48,643 --> 00:40:49,643
Bingo!
425
00:40:50,478 --> 00:40:51,478
Oh, bingo!
426
00:40:52,007 --> 00:40:55,142
The intricate beauty
of a snowflake is at first
427
00:40:55,143 --> 00:40:58,941
sight baffling, given the
simplicity of their story.
428
00:40:59,676 --> 00:41:02,361
But in fact, it's a gift.
429
00:41:02,751 --> 00:41:05,040
A gift of almost nothing.
430
00:41:05,895 --> 00:41:10,120
One frozen moment that can reveal how the
underlying story, the underlying laws of
431
00:41:10,121 --> 00:41:13,799
nature, can lead to seemingly infinite
complexity.
432
00:41:19,288 --> 00:41:24,957
Because snowflakes form in minutes and are
made out of a single ingredient with
433
00:41:24,958 --> 00:41:28,413
strange properties that
give rise to a vast array of
434
00:41:28,414 --> 00:41:33,616
naturally occurring forms of all
shapes, sizes and behaviours.
435
00:41:37,635 --> 00:41:38,635
Ice.
436
00:41:46,824 --> 00:41:50,303
涄 You know, it's so mystical when you
leave in a morning in the fog.
437
00:41:51,503 --> 00:41:53,103
You're just looking around.
438
00:41:55,163 --> 00:41:58,102
And then you see these shapes that come
out of the fog.
439
00:42:07,991 --> 00:42:10,150
They're big, big heavy objects.
440
00:42:10,330 --> 00:42:14,570
Far bigger than anything we've created
floating on the sea.
441
00:42:34,837 --> 00:42:37,827
We've got to remember it
was an iceberg that sailed
442
00:42:37,867 --> 00:42:40,556
past Newfoundland, which
ended up sinking the Titanic.
443
00:42:44,285 --> 00:42:46,395
Doug Allen is here because it's iceberg
season.
444
00:42:49,249 --> 00:42:51,094
He's part of a scientific expedition.
445
00:42:51,734 --> 00:42:56,653
Every summer, thousands of icebergs float
south from the Arctic into the shipping
446
00:42:56,654 --> 00:42:59,553
lanes and oil fields off the coast of
Newfoundland.
447
00:43:02,152 --> 00:43:07,612
This team are here to help protect those
multi-billion-dollar industries by trying
448
00:43:07,613 --> 00:43:10,431
to understand more about where the
icebergs are heading.
449
00:43:11,991 --> 00:43:15,050
The man leading the expedition is Neil
Riggs.
450
00:43:15,660 --> 00:43:19,610
So you put it back in the water again,
OK, and if we lose, well, then we take it
451
00:43:19,611 --> 00:43:22,809
in, we secure it, and if that goes
nowhere, we go home.
452
00:43:26,309 --> 00:43:28,628
The big problem with icebergs is simple.
453
00:43:29,268 --> 00:43:30,268
They float.
454
00:43:37,987 --> 00:43:41,986
Iceberg ice reflects radar
69 times less effectively
455
00:43:41,987 --> 00:43:44,587
than a ship of the same
cross-sectional area.
456
00:43:47,025 --> 00:43:54,324
So you could be sailing along and doing
very good seamanship, looking at your
457
00:43:54,325 --> 00:43:58,444
radar, and there's the thing all of a
sudden, and you're upon it, and it's still
458
00:43:58,445 --> 00:44:00,443
a massive piece of ice relative to your
ship.
459
00:44:01,173 --> 00:44:02,613
So it could make a nice little hole.
460
00:44:04,943 --> 00:44:09,142
The team will have to understand the
influence of a large number of variables
461
00:44:09,143 --> 00:44:14,001
if they are to distinguish between
harmless icebergs and dangerous ones.
462
00:44:14,841 --> 00:44:16,581
It's a complicated jigsaw.
463
00:44:16,641 --> 00:44:19,400
It's a little bit, you could think of it
as a crime scene where you have the
464
00:44:19,401 --> 00:44:21,947
forensic people go in
and they pick up little bits
465
00:44:21,948 --> 00:44:24,541
of clues and together
you make a bigger picture.
466
00:44:25,600 --> 00:44:30,159
What I'm doing is just adding my little
piece to the overall picture and hopefully
467
00:44:30,160 --> 00:44:33,818
helping their mathematical models to be
more real.
468
00:44:36,273 --> 00:44:38,338
Doug is a specialist cold water diver.
469
00:44:39,342 --> 00:44:42,777
It's his job to photograph the underside
of the icebergs.
470
00:44:43,457 --> 00:44:46,276
Go on up to some of those smaller pieces,
please.
471
00:44:46,277 --> 00:44:46,596
Okay.
472
00:44:46,736 --> 00:44:47,196
Okay.
473
00:44:47,656 --> 00:44:50,976
Yes, Captain Manning, are we okay to put
the divers on?
474
00:44:50,977 --> 00:44:52,755
Rick Stanley is looking after safety.
475
00:44:58,954 --> 00:45:00,274
Who knows what's going to happen?
476
00:45:00,344 --> 00:45:05,563
There's so much pressure in this ice that
it blows, it explodes.
477
00:45:05,564 --> 00:45:10,583
But there's pressure in there that can
blow a piece of iceberg off the ice,
478
00:45:11,142 --> 00:45:12,722
probably 15 or 20 feet.
479
00:45:19,741 --> 00:45:23,601
And we were just pottering around and
suddenly, with no warning at all,
480
00:45:23,846 --> 00:45:25,712
the whole thing
split in half and it was
481
00:45:25,713 --> 00:45:29,161
almost like it was all
falling into each other.
482
00:45:36,719 --> 00:45:38,118
This might be a bit unstable.
483
00:45:38,538 --> 00:45:40,078
This is a huge bird.
484
00:45:41,118 --> 00:45:44,057
I'd rather dive around one that wasn't
falling apart.
485
00:45:44,457 --> 00:45:45,457
Yeah.
486
00:45:48,797 --> 00:45:53,776
These giant frozen mountains are born from
the most innocent beginnings.
487
00:45:59,935 --> 00:46:00,935
Snowflakes.
488
00:46:03,114 --> 00:46:06,751
Over thousands of years,
they're compressed to
489
00:46:06,752 --> 00:46:10,633
form glaciers, but then
break off to form icebergs.
490
00:46:11,553 --> 00:46:14,533
An average one weighs 200,000 tonnes.
491
00:46:16,672 --> 00:46:22,352
And that, give or take, is around 100
trillion snowflakes that form the
492
00:46:22,353 --> 00:46:25,817
structures that the expedition
is trying to model, using a
493
00:46:25,818 --> 00:46:29,930
combination of sonar robots and
Doug's first-hand observations.
494
00:46:32,430 --> 00:46:34,490
I basically have a
good look at one side of
495
00:46:34,491 --> 00:46:37,550
the bed between the
surface and 30 metres.
496
00:46:37,869 --> 00:46:40,515
Tell them what I saw
and it will mean that they
497
00:46:40,516 --> 00:46:42,828
can interpret the sonar
data that comes back.
498
00:46:42,968 --> 00:46:45,548
They'll get a better idea of it if I've
seen it for myself.
499
00:47:14,883 --> 00:47:18,163
It's quite eerie going down the side of
the iceberg.
500
00:47:19,763 --> 00:47:24,382
You're going down into the darkness,
into the blue, into the green.
501
00:47:30,571 --> 00:47:35,550
And very occasionally there'll be this
really loud thump, just like someone had
502
00:47:35,551 --> 00:47:38,890
hit you with the flat of their hand in the
centre of your chest.
503
00:47:40,789 --> 00:47:43,209
Where the iceberg is banging on the
bottom.
504
00:47:51,738 --> 00:47:54,977
You really don't want to go
too far down because there is
505
00:47:54,978 --> 00:47:57,537
a real danger of being squished
by the iceberg underneath.
506
00:48:03,426 --> 00:48:05,716
Well, you always worry when divers are in
the water.
507
00:48:06,151 --> 00:48:10,061
But iceberg diving, there's
even more of that anticipation
508
00:48:10,062 --> 00:48:13,994
and excitement that goes on
in the lower part of your belly.
509
00:48:22,913 --> 00:48:26,212
So you swim in and you begin to see the
details.
510
00:48:26,332 --> 00:48:30,472
You begin to realise that this is not a
flat boat.
511
00:48:30,492 --> 00:48:32,212
This is a wall of ice going into the
depths.
512
00:48:32,571 --> 00:48:37,111
This has tiny little dimples on it which
almost looks like a giant golf ball.
513
00:48:44,170 --> 00:48:48,809
These features are added to the models to
understand how they affect the way the
514
00:48:48,810 --> 00:48:53,348
icebergs float and travel over long
distances and into the shipping lanes.
515
00:48:55,768 --> 00:48:59,127
It's good to contribute to science at a
basic level like this.
516
00:48:59,452 --> 00:49:02,479
When the science is still
developing, to come in, take some
517
00:49:02,480 --> 00:49:04,787
shots, which help the
scientists, that's really useful.
518
00:49:10,156 --> 00:49:16,236
For all their unpredictability, there is
regularity in the behaviour of icebergs.
519
00:49:18,934 --> 00:49:22,834
If you look carefully and ask the right
questions.
520
00:49:23,534 --> 00:49:25,433
Which is what science is all about.
521
00:49:32,642 --> 00:49:37,171
And the simplest question of all is about
the most obvious part of their behaviour.
522
00:49:40,996 --> 00:49:41,996
Why does ice float?
523
00:49:44,510 --> 00:49:45,630
That's not a naive question.
524
00:49:46,220 --> 00:49:50,030
Because no other commonly occurring solid
floats on its own liquid.
525
00:49:52,619 --> 00:49:56,189
The answer lies in the structure of the
water molecule itself.
526
00:49:58,168 --> 00:49:59,308
Think of what a molecule is.
527
00:49:59,448 --> 00:50:01,508
Take a water molecule for example.
528
00:50:02,228 --> 00:50:05,567
It's two hydrogen atoms stuck to an oxygen
atom.
529
00:50:06,347 --> 00:50:12,706
That's two hydrogen nuclei which have
positive electric charge sticking to an
530
00:50:12,707 --> 00:50:15,606
oxygen nucleus which has a positive
electric charge.
531
00:50:16,345 --> 00:50:19,345
And they're surrounded by negatively
charged electrons.
532
00:50:19,740 --> 00:50:21,785
That's what sticks the atoms together.
533
00:50:22,385 --> 00:50:27,624
The negatively charged electrons tend to
cluster around the oxygen nucleus,
534
00:50:28,364 --> 00:50:34,363
leaving those two legs of hydrogen
slightly positively charged.
535
00:50:35,133 --> 00:50:39,842
That means that those positive charges can
attract other There are other negatively
536
00:50:40,142 --> 00:50:42,501
charged ends of other water molecules.
537
00:50:42,941 --> 00:50:47,901
So an oxygen can come and orientate itself
and bond to that leg.
538
00:50:48,790 --> 00:50:52,560
On the other side, another oxygen from
another water molecule will be attracted
539
00:50:52,660 --> 00:50:55,539
to the positive charge and bond to that
leg.
540
00:50:55,979 --> 00:50:58,759
On the top, you get a hydrogenate bonding
to that leg.
541
00:50:59,079 --> 00:51:02,507
So you can see you build
up a structure, an open
542
00:51:02,557 --> 00:51:06,418
crystal structure, a shape
which is actually hexagonal.
543
00:51:07,093 --> 00:51:12,057
And it's that property, that open
structure, which is a reflection of the
544
00:51:12,058 --> 00:51:17,071
underlying structure of the
water molecule itself, that
545
00:51:17,072 --> 00:51:21,115
leads to the solid ice being
less dense than the liquid.
546
00:51:21,515 --> 00:51:27,954
And that is why ice cubes and icebergs
float on liquid water.
547
00:51:31,774 --> 00:51:35,392
The hexagonal structure
of ice is a shadow of the
548
00:51:35,393 --> 00:51:38,174
forces of nature that
hold molecules together.
549
00:51:43,312 --> 00:51:46,472
Forces that shape every molecule of water.
550
00:51:48,081 --> 00:51:52,091
And that create a six-fold symmetry of
snowflakes.
551
00:51:57,130 --> 00:51:58,820
You can tell they're all the same thing.
552
00:51:59,780 --> 00:52:00,879
They're all six-sided.
553
00:52:02,539 --> 00:52:07,118
And yet you can also see, just by eye,
that everyone is different.
554
00:52:07,258 --> 00:52:08,498
Some are radically different.
555
00:52:09,708 --> 00:52:10,658
It's very difficult to imagine.
556
00:52:10,659 --> 00:52:18,577
How all this beauty and complexity could
emerge spontaneously from a few simple
557
00:52:18,727 --> 00:52:19,726
laws of nature.
558
00:52:25,226 --> 00:52:27,620
As snowflakes fall
through the sky, they
559
00:52:27,621 --> 00:52:30,906
form and grow around a
symmetrical framework.
560
00:52:33,324 --> 00:52:39,523
So if you start with an ice crystal and
some part of it's got a flat bit,
561
00:52:40,413 --> 00:52:45,083
part of the hexagon if you like,
and some bits a bit rough, then water
562
00:52:45,084 --> 00:52:49,122
molecules are more likely to bind to the
rough bit than the flat bit.
563
00:52:49,402 --> 00:52:53,741
There are basically more ways for them,
more sites for them to stick to.
564
00:52:54,341 --> 00:52:58,420
So that means that the rough bit will
accumulate more molecules than the flat
565
00:52:58,620 --> 00:53:02,020
bit, and it'll build up faster until it
gets flat.
566
00:53:02,530 --> 00:53:03,530
And then it'll slow down.
567
00:53:04,060 --> 00:53:09,499
So there's a tendency for the underlying
structure of the ice crystals themselves
568
00:53:09,500 --> 00:53:12,558
to get echoed into bigger and bigger
units.
569
00:53:14,618 --> 00:53:18,397
Then there's a second process called
branching or the branch instability.
570
00:53:19,542 --> 00:53:24,476
That happens when the snowflake goes into
a particularly humid region in a cloud.
571
00:53:24,696 --> 00:53:27,496
So that's a region where there are lots of
water molecules available.
572
00:53:28,466 --> 00:53:31,075
So you get a little bump on the flat
surface.
573
00:53:31,915 --> 00:53:37,155
That bump is more likely to have water
molecules bind to it.
574
00:53:37,484 --> 00:53:39,434
It's got more binding sites, if you like.
575
00:53:39,494 --> 00:53:40,494
So it'll grow quickly.
576
00:53:40,495 --> 00:53:42,754
There are lots of water molecules
available.
577
00:53:43,494 --> 00:53:45,527
So it'll grow into a
spike and then other
578
00:53:45,528 --> 00:53:48,894
bumps can appear and
they'll grow into spikes.
579
00:53:49,023 --> 00:53:53,892
So that's how you get that star-like,
sharp structures on snowflakes.
580
00:53:55,282 --> 00:53:59,851
But then if the snowflake drifts back into
a region that's less humid, so there are
581
00:53:59,852 --> 00:54:04,630
less water molecules available,
then the faceting takes over again and
582
00:54:04,631 --> 00:54:08,130
smooth edges, hexagonal structures start
to form.
583
00:54:08,805 --> 00:54:10,369
Then it goes into a humid region.
584
00:54:10,789 --> 00:54:12,909
And the branching takes over and you get
the branches.
585
00:54:22,188 --> 00:54:24,697
It's a wonderfully complex and intricate
process.
586
00:54:25,122 --> 00:54:29,356
And the thing I find most beautiful about
it is that when you look at a snowflake,
587
00:54:29,806 --> 00:54:32,196
then you can read its entire history.
588
00:54:32,276 --> 00:54:35,036
You can see its history made solid.
589
00:54:38,515 --> 00:54:41,835
Every individual snowflake has a different
history.
590
00:54:41,930 --> 00:54:45,135
Every snowflake
followed a slightly different
591
00:54:45,136 --> 00:54:47,674
path through the
clouds into the ground.
592
00:54:48,264 --> 00:54:53,293
And that means every snowflake grew in a
subtly different way.
593
00:54:53,873 --> 00:54:57,152
And that's why no two snowflakes are ever
alike.
594
00:54:57,472 --> 00:55:01,851
Because no two paths through time are ever
alike.
595
00:55:09,170 --> 00:55:13,148
When you look at a
snowflake, you see history
596
00:55:13,149 --> 00:55:17,030
and the deep structure
of nature condensed.
597
00:55:17,389 --> 00:55:19,109
Into a frozen moment.
598
00:55:20,539 --> 00:55:24,398
How many stars it is together?
599
00:55:25,968 --> 00:55:27,517
You can see them so clearly.
600
00:55:30,617 --> 00:55:31,617
You look.
601
00:55:32,217 --> 00:55:35,436
It is wonderful, you know, that when you
think about it, the whole universe,
602
00:55:35,556 --> 00:55:39,096
the whole of physics is contained in a
snowflake.
603
00:55:39,706 --> 00:55:43,535
To describe them, you need all four forces
of nature.
604
00:55:44,395 --> 00:55:47,321
You need gravity to
allow the snowflake to fall
605
00:55:47,322 --> 00:55:49,454
down through the clouds
and onto the ground.
606
00:55:49,455 --> 00:55:53,244
You need electromagnetism
to stick all those water
607
00:55:53,245 --> 00:55:57,273
molecules together to
form these beautiful crystals.
608
00:55:58,073 --> 00:56:03,012
You need the nuclear forces to stick the
atomic nuclei of oxygen together.
609
00:56:03,772 --> 00:56:09,251
And then you need to understand about
symmetry and symmetry breaking.
610
00:56:09,651 --> 00:56:13,256
All the fundamental ideas that
underlie modern physics can
611
00:56:13,257 --> 00:56:16,810
be thought of in the journey
of a snowflake to the ground.
612
00:56:28,118 --> 00:56:33,687
Every snowflake shares the same building
blocks, the same basic, beautiful,
613
00:56:33,887 --> 00:56:37,467
symmetric forces of nature at their heart.
614
00:56:37,747 --> 00:56:40,746
But because of their histories,
because of the way they formed,
615
00:56:40,986 --> 00:56:41,986
they're all different.
616
00:56:42,786 --> 00:56:44,366
And so it is with solar systems.
617
00:56:44,506 --> 00:56:45,865
So it is with planets.
618
00:56:46,185 --> 00:56:47,865
And so it is with people.
619
00:56:48,475 --> 00:56:52,684
We're all made out of the same building
blocks, but we're all slightly and
620
00:56:52,685 --> 00:56:56,604
magnificently different because of the
history of our formation.
621
00:57:04,847 --> 00:57:09,492
The structures we see in the universe,
stars and planets and trees and
622
00:57:09,493 --> 00:57:12,711
snowflakes, are shadows of something
deeper.
623
00:57:14,671 --> 00:57:19,070
They mask an underlying beauty and
simplicity.
624
00:57:20,990 --> 00:57:28,529
But isn't it a beautiful thought that our
origin and evolution, just like the
625
00:57:28,530 --> 00:57:32,165
structure of a snowflake
in a snowstorm, can
626
00:57:32,265 --> 00:57:36,628
be explained by a few
simple natural laws?
627
00:57:37,188 --> 00:57:40,479
And isn't it a wonderful idea
that that thought came from
628
00:57:40,480 --> 00:57:45,266
just looking carefully at nature
and trying to understand it?
54637
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