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When I first
started making programmes,
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the origin of life
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and the structure of DNA was unknown
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The fact that continents might
drift across the surface
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of the planet was ridiculed.
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Then, science was something you
did in museums and laboratories.
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Today, that's very different.
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Today, scientists travel to
the farthest ends of the Earth.
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As a result of their discoveries,
we can now make sense of what
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not so long ago
seemed baffling mysteries.
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And for the last 60 years, I've been
travelling in the footsteps,
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trying to translate
some of their insights into film.
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Early in my television career,
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I met the distinguished Austrian
scientist Konrad Lorenz,
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who was one of the first to try
and understand animal behaviour.
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He worked with geese,
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and he discovered that
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if he was the first thing that young
goslings saw when they hatched,
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they would follow him
wherever he went.
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It was as if he had
become their parent.
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He called as this process imprinting
and as a result of it,
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the young continued to follow him,
even as adults.
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In 1952, Professor Lorenz published
a book explaining how
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he could talk to animals and,
in particular, to greylag geese.
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It was called King Solomon's Ring,
and this is it.
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And I was given
the job of interviewing him
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on live television about it.
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And I started by saying,
now Professor Lorenz, I understand
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you can speak
greylag goose language,
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and I actually have
a greylag goose here
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for you to have a few words with.
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And the goose was very upset,
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flapped its wings
and went, phhhhht, like this,
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and Lorenz said, "Oh, dear,
oh, dear! All over ze trousers!"
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And, very embarrassed,
took his handkerchief
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and then blew his nose
which produced a great smear
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of goose droppings
all down his cheek.
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And I had to continue
asking him serious questions
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about animal behaviour while
he was covered in goose droppings.
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But at least he saw the joke,
because after it was all over,
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he took his book and he drew a nice
little cartoon of the whole event
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in the front for me.
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Today,
film-makers use this imprinting
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technique for their own purposes.
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The first living creature these
young goslings saw was Rose Buck,
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and they stayed with her.
They even shared her bed with her.
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Who am I?
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Off you go, then.
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Good boys! Come on, then!
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So now they too follow her
everywhere.
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On foot...
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..and, eventually, even in flight.
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These are greylag geese,
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the same species that Konrad Lorenz
worked with.
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And they are following me
because, like his geese,
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but they've been
imprinted on a human being.
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And that human being,
of course, is Rose.
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HE LAUGHS
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You see, they're all flying
straight in line behind one another,
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just as they do in the wild.
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That's because
there's a little turbulence
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from the end of the wing there,
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which makes it easier
for that one to get lift,
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so they save energy
by flying in this way.
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But who could have dreamt
that it would have been possible
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to be sitting alongside one
as they do that?
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Look at them.
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Isn't it wonderful?
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00:06:13,720 --> 00:06:16,000
The discovery of imprinting,
of course,
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was more than just a boon
to film-makers.
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00:06:19,000 --> 00:06:23,120
It threw a new light not
only on the behaviour of many birds,
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but of animals of all kinds,
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including mammals
and, indeed, ourselves.
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00:06:30,760 --> 00:06:32,840
But back in the 50s
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other scientists were tackling some
even more mind-boggling problems.
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For example, we knew next to nothing
about that great mystery of all,
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the origin of life.
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And then in 1952, the year
I happened to join television,
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a young postgraduate student
at the University of Chicago,
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Stanley Miller, decided to try
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and recreate the conditions of
the early Earth in the laboratory.
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It was a remarkably ambitious
project for a 22-year-old student.
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He used apparatus like this.
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In the bottom flask
is boiling water.
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Steam from it rises up here
through these tubings
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and goes to this flask here,
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which he'd filled with
a mixture of gases,
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methane, ammonia and hydrogen,
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which are thought to have been
present in the early atmosphere.
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And through that,
he passed an electric discharge
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from these two electrodes,
mimicking lightning.
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Stanley Miller
was working against a deadline.
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His professor
had given him six months.
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If by the end of that time
he had gone no results,
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he had to abandon these experiments
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and return to working on his PhD,
which was about meteorites.
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But his intuition proved correct.
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A week later, he found a brown
liquid in the bottom of the flask.
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It contained amino acids,
the building blocks of life.
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Stanley Miller had demonstrated
that the first steps on the path
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leading to life could have
happened spontaneously.
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00:09:03,960 --> 00:09:05,960
Conditions very similar to those
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created by Miller
in his laboratory do actually
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exist in the natural world today,
in volcanic hot springs.
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00:09:15,320 --> 00:09:20,560
So when, in 1979, we came to make
a series called Life on Earth,
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00:09:20,560 --> 00:09:24,360
it seemed a good idea
to start our story beside
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just such a hot spring in
Yellowstone National Park, Wyoming.
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And in these springs, staining
them a whole variety of colours,
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there flourish micro-organisms.
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Micro-organisms that look
to be almost identical
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with some of the earliest fossils
that we know.
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But even as we were filming
Life on Earth,
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there was a momentous discovery,
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one that suggested a different
location for the origin of life.
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In 1979,
the deep-water submersible Alvin,
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working near the Galapagos Islands,
descended more than 2,000 metres
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to the floor of the Pacific Ocean.
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Its mission was to film
a volcanic activity.
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00:10:16,120 --> 00:10:18,720
But instead of a barren
volcanic landscape,
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its searchlights revealed a whole
community of hitherto-unknown
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00:10:22,200 --> 00:10:25,000
animals that were
living in this black this.
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00:10:26,920 --> 00:10:31,040
There were giant tube worms nearly
a metre long, and among them,
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small fish and crabs.
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00:10:35,640 --> 00:10:38,000
But what were all these
creatures feeding on,
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so far from the energy of the sun?
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00:10:43,160 --> 00:10:46,040
Plumes of water superheated
by the molten rock
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deep in the Earth's crust
were spouting into the cold sea,
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00:10:50,160 --> 00:10:53,080
and the chemical compounds
they carried
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were being deposited
as great, rocky towers.
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00:11:01,720 --> 00:11:05,640
Some of the dissolved chemicals
were serving as food for bacteria.
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00:11:07,000 --> 00:11:10,880
The bacteria nourished the tube worm
and they, in turn,
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were food for crabs and fish.
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00:11:17,360 --> 00:11:19,800
More of these astonishing ecosystems
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have now been discovered elsewhere
in the world's oceans,
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each with its
own unique inhabitants.
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00:11:32,920 --> 00:11:37,600
Clearly events such as these
could have supported
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the first micro-organisms
that appeared in the primeval seas
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nearly 4,000 million years ago.
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00:11:47,560 --> 00:11:50,400
But, if so, how did those
early forms of life give rise
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to the great diversity
of creatures that live today?
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That problem has puzzled thinkers
since the very beginning of science.
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00:12:05,240 --> 00:12:08,960
In the 19th century,
zoology was still at stage
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of collecting
and identifying species.
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00:12:12,240 --> 00:12:15,200
People went out
to the wilder parts of the world
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and shot an animal,
often the bigger, the better,
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00:12:17,960 --> 00:12:22,400
and then brought them back in order
to be measured and identified.
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And here in the storerooms
of London's Natural History Museum,
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you can see some of the fruits
of their endeavours.
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These specimens, carefully arranged
in groups of similar species,
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together form
a catalogue of life on the planet.
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It was Charles Darwin who made sense
of this vast catalogue
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with his theory of evolution
by natural selection.
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And in 1979,
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we used to that theory as the basis
of that television series
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surveying the whole of the natural
world which we called Life on Earth.
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There are some four million
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different kinds of animals
and plants in the world.
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Four million different solutions
to the problems of staying alive.
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This is the story of how a few
of them came to be as they are.
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00:13:27,560 --> 00:13:28,880
Early on in the series,
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I went to the Galapagos to have
a look at the animals that had
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provided Darwin with evidence
for his theory, the giant tortoises.
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This one, for example,
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with its deep rounded shell,
comes from a well-watered island
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where it can feed
mainly on vegetation on the ground.
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This one, on the other hand,
has a peak to the front of its shell
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that enables it
to stretch its long neck upwards.
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It comes from an arid island where
the tortoises often have to crane up
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to reach the only food available,
the branches of trees and cactus.
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00:14:07,400 --> 00:14:11,080
The suspicion grew in Darwin's mind
that species were not fixed forever.
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00:14:11,080 --> 00:14:15,080
Perhaps these tortoises were
all descended from common ancestors
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and had changed
to suit their particular islands.
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00:14:23,040 --> 00:14:26,320
The differences that Darwin
had noticed amongst these
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Galapagos animals were,
of course, more tiny.
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00:14:29,800 --> 00:14:32,760
But if they could develop,
wasn't it possible that,
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over the thousands
or millions of years,
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a whole series of such differences
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might add up
to one revolutionary change?
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00:14:41,560 --> 00:14:46,080
He gave the idea irresistible force
by suggesting a mechanism
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00:14:46,080 --> 00:14:48,080
which might have bought that about.
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He called the mechanism
natural selection.
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00:14:53,440 --> 00:14:57,320
So, Darwin had explained
how different species evolved.
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00:14:58,560 --> 00:15:01,360
But he also proposed that all life
was inter-related,
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having come from a common origin.
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00:15:05,200 --> 00:15:08,400
That, of course, implied
the existence of intermediate forms,
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links between
the great animal groups.
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00:15:12,760 --> 00:15:17,120
One leading candidate connecting
fish to amphibians had already
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been discovered in the rivers
of northern Australia, the lungfish.
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00:15:22,640 --> 00:15:25,240
Although it lives in water,
just like an ordinary fish,
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00:15:25,240 --> 00:15:28,440
it can also breathe air
through a pouch in its throat,
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like a simple lung.
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And it punts itself along the river
bottom using two pairs
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of muscular fins, placed low
on its body, just like simple legs.
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00:15:40,480 --> 00:15:44,120
But the actual ancient creature
that linked fish
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00:15:44,120 --> 00:15:48,440
and the first land-living creatures
wasn't found until very recently.
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00:15:49,520 --> 00:15:53,520
Fossils of fish very
like these Australian lungfish
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00:15:53,520 --> 00:15:59,240
are known from rocks
that are some 400 million years old.
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00:15:59,240 --> 00:16:03,480
And we can be pretty sure that those
ancient fish could breathe air.
199
00:16:04,560 --> 00:16:08,680
But could they manage to get out
of the water and up onto the land?
200
00:16:09,840 --> 00:16:13,760
How could they have managed that?
Nobody could be sure.
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00:16:13,760 --> 00:16:15,640
There was a missing link.
202
00:16:16,920 --> 00:16:20,840
And then, this turned up in 2004.
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00:16:23,480 --> 00:16:27,520
This was found in Arctic Canada
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00:16:27,520 --> 00:16:30,360
and was called tiktaalik.
205
00:16:31,840 --> 00:16:34,400
You see, it's about the same size
as a lungfish but it's got
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00:16:34,400 --> 00:16:40,920
a skull which is flattened that way,
and a row of formidable teeth.
207
00:16:40,920 --> 00:16:42,120
But what about its limbs?
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00:16:42,120 --> 00:16:45,720
Well, a number of specimens
of its limbs have been found,
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00:16:45,720 --> 00:16:47,480
and here's one of them.
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It had a fleshy base,
just like a lungfish,
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00:16:51,920 --> 00:16:56,080
but it also had a joint
in the middle of that limb.
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00:16:56,080 --> 00:17:01,600
An elbow. And at the end,
a range of digits.
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00:17:01,600 --> 00:17:04,920
This, almost certainly,
was the first limb
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00:17:04,920 --> 00:17:08,720
to move a creature up onto land.
215
00:17:11,120 --> 00:17:15,280
So, tiktaalik probably looked
a bit like present-day amphibians,
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00:17:15,280 --> 00:17:16,840
such as salamanders.
217
00:17:16,840 --> 00:17:19,600
The link between fish and
land-living animals
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00:17:19,600 --> 00:17:22,080
had now been found.
219
00:17:22,080 --> 00:17:25,560
Another piece in the jigsaw of life
had been put in place.
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00:17:28,480 --> 00:17:32,680
But, 60 years ago,
there was another baffling puzzle.
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00:17:32,680 --> 00:17:35,840
The odd way in which animals
are distributed it on our planet.
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00:17:38,960 --> 00:17:42,640
For example, why is it that
closely related groups of animals
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00:17:42,640 --> 00:17:44,280
can occur on both sides of an ocean,
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00:17:44,280 --> 00:17:46,560
in West Africa and South America,
for example?
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00:17:49,120 --> 00:17:51,680
Well, birds could fly
across the ocean, yes.
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00:17:51,680 --> 00:17:54,480
Mammals and reptiles, well,
conceivably they might have
227
00:17:54,480 --> 00:17:59,040
floated across on rafts of
vegetation, but what about frogs?
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00:17:59,040 --> 00:18:02,120
Frogs like this one.
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00:18:02,120 --> 00:18:05,440
Frogs have permeable skins,
and they're poisoned by salt water,
230
00:18:05,440 --> 00:18:09,320
so they couldn't
have floated across.
231
00:18:09,320 --> 00:18:14,000
But maybe it wasn't the frogs that
moved, maybe it was the continents.
232
00:18:20,160 --> 00:18:23,320
That was the suggestion
that was being debated
233
00:18:23,320 --> 00:18:26,720
when I was a geology student
at Cambridge in 1945.
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00:18:28,280 --> 00:18:32,440
Could it be that the continents of
the Earth were fragments of a much
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00:18:32,440 --> 00:18:36,480
larger super-continent that, over
millions of years had drifted apart?
236
00:18:40,000 --> 00:18:44,600
So, I asked the Professor of Geology
here at Cambridge University
237
00:18:44,600 --> 00:18:48,720
why he didn't tell us students
about that possibility.
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00:18:48,720 --> 00:18:51,120
And he replied, rather loftily,
239
00:18:51,120 --> 00:18:54,120
"When you can demonstrate that there
is a force
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00:18:54,120 --> 00:18:59,480
that will move a continent
by a millimetre, I will consider it.
241
00:18:59,480 --> 00:19:03,440
But until then,
the idea is moonshine, dear boy."
242
00:19:05,640 --> 00:19:10,640
But, by the time I came to make
The Living Planet in 1984,
243
00:19:10,640 --> 00:19:12,400
the answer had become clear.
244
00:19:12,400 --> 00:19:13,920
And I thought
245
00:19:13,920 --> 00:19:15,960
that one of the most
dramatic ways to reveal it
246
00:19:15,960 --> 00:19:18,600
would be to stand high up
in the greatest mountain
247
00:19:18,600 --> 00:19:20,680
range on earth, the Himalayas.
248
00:19:22,440 --> 00:19:28,040
They were raised to their present
height about 65 million years ago
249
00:19:28,040 --> 00:19:30,400
from the bottom of the sea.
250
00:19:30,400 --> 00:19:34,880
And what is the evidence
for that extraordinary statement?
251
00:19:34,880 --> 00:19:38,320
Well, it can be found all over
the place, just up here.
252
00:19:43,520 --> 00:19:47,400
These slopes are littered...
253
00:19:48,520 --> 00:19:50,280
..with fragments...
254
00:19:52,080 --> 00:19:53,280
..like these.
255
00:19:54,880 --> 00:19:59,760
This is obviously a shell that
has been turned to stone, a fossil.
256
00:19:59,760 --> 00:20:03,040
But I'm about as far as possible
as it is to be from the sea.
257
00:20:03,040 --> 00:20:05,440
Not only am I
in the middle of Asia,
258
00:20:05,440 --> 00:20:07,520
hundreds of miles from the sea,
259
00:20:07,520 --> 00:20:11,280
but I'm over two vertical miles
above its level.
260
00:20:11,280 --> 00:20:16,240
What forces could possibly have
raised the seabed to these heights?
261
00:20:16,240 --> 00:20:19,280
Well, we now know that those forces
are still in action.
262
00:20:25,120 --> 00:20:31,280
These Icelandic volcanoes erupt
from huge cracks, or fissures,
263
00:20:31,280 --> 00:20:33,640
which regularly open up
in the line which runs
264
00:20:33,640 --> 00:20:36,520
right across the width
of the island.
265
00:20:36,520 --> 00:20:40,840
And that line itself
is only the northern end
266
00:20:40,840 --> 00:20:44,520
of a huge line of weakness
that runs for thousands of miles
267
00:20:44,520 --> 00:20:47,960
southwards from Iceland,
right round the side of the globe.
268
00:20:50,520 --> 00:20:54,600
And the sheer weight of these
molten ingots of rock prevents them
269
00:20:54,600 --> 00:20:57,280
from being swept away
from the vent by the gale,
270
00:20:57,280 --> 00:21:01,440
so there's little danger
of them suddenly coming our way.
271
00:21:01,440 --> 00:21:05,960
Well, there were pieces of lava
the size of a suitcase landing
272
00:21:05,960 --> 00:21:08,800
with a thud into the ash plain
as we stood.
273
00:21:08,800 --> 00:21:12,280
And you could see them
glowing red hot and thumping down
274
00:21:12,280 --> 00:21:17,440
into the ash, and the question
is just how close could you get.
275
00:21:17,440 --> 00:21:20,920
Well, we got quite close enough,
and when a lump of lava
276
00:21:20,920 --> 00:21:24,080
did actually land only
about three or four feet behind me,
277
00:21:24,080 --> 00:21:26,880
I thought the time
had come to leave.
278
00:21:29,880 --> 00:21:32,200
Now we know that
it was eruptions like these,
279
00:21:32,200 --> 00:21:36,440
but at the bottom of the sea,
that explain the mystery.
280
00:21:38,400 --> 00:21:41,400
Molten rock
rises from the Earth's core.
281
00:21:44,120 --> 00:21:48,520
Near the surface, the rock spreads
in two directions and go sideways.
282
00:21:49,560 --> 00:21:50,880
It begins to lose heat.
283
00:21:52,880 --> 00:21:57,120
Eventually the much-cooler rock
sinks back down.
284
00:21:58,320 --> 00:22:00,240
Through this spreading process,
285
00:22:00,240 --> 00:22:03,600
the Earth's crust
is very slowly dragged apart.
286
00:22:05,520 --> 00:22:09,280
And it is this that ultimately
makes the continents move.
287
00:22:12,200 --> 00:22:16,440
So, what in my youth was no more
than a speculative theory
288
00:22:16,440 --> 00:22:18,280
is now fully accepted.
289
00:22:18,280 --> 00:22:20,120
Continents do drift.
290
00:22:22,120 --> 00:22:25,280
The Indian sub-continent
has moved north,
291
00:22:25,280 --> 00:22:29,040
pushing up the sediments that had
accumulated on the sea floor
292
00:22:29,040 --> 00:22:31,840
ahead of it to form the Himalayas.
293
00:22:32,840 --> 00:22:36,920
Which is how my fossilised sea shell
came to rest in mountains
294
00:22:36,920 --> 00:22:38,440
over two miles high.
295
00:22:41,680 --> 00:22:45,960
So, continental drift
explains why animals
296
00:22:45,960 --> 00:22:48,800
are distributed in the way they are
around the world.
297
00:22:48,800 --> 00:22:52,480
But why do they behave
in the way they do?
298
00:22:52,480 --> 00:22:56,000
Well, that has also been
the subject of an investigation
299
00:22:56,000 --> 00:22:57,560
in the last few decades.
300
00:22:57,560 --> 00:23:01,240
In particular, how do
they communicate with one another?
301
00:23:01,240 --> 00:23:05,440
Filming that gave me a chance
to join in those conversations.
302
00:23:08,960 --> 00:23:12,800
A double knock on a tree
is a statement used by
303
00:23:12,800 --> 00:23:17,080
a Patagonian woodpecker to say that
this patch of the forest is mine.
304
00:23:17,080 --> 00:23:19,000
And if someone else claims it,
305
00:23:19,000 --> 00:23:21,920
he'll certainly knock out
a challenge and come to investigate.
306
00:23:40,400 --> 00:23:43,720
North American male cicadas,
singing their deafening song,
307
00:23:43,720 --> 00:23:46,760
can be summoned by the noise
of a female's wing flick
308
00:23:46,760 --> 00:23:48,800
that sounds like a finger snap.
309
00:23:55,120 --> 00:23:56,600
Now, can I bring you back?
310
00:23:57,920 --> 00:24:00,800
And a male
wants to investigate that.
311
00:24:00,800 --> 00:24:03,760
How about coming this way?
312
00:24:07,680 --> 00:24:12,920
Oh, the noise is awful!
313
00:24:14,400 --> 00:24:17,760
In Minnesota,
it's not difficult to summon a wolf.
314
00:24:17,760 --> 00:24:21,080
HE HOWLS
315
00:24:25,080 --> 00:24:26,560
HE HOWLS
316
00:24:27,720 --> 00:24:30,560
HE IMITATES BIRD
317
00:24:30,560 --> 00:24:32,840
On Australia's Lord Howe Island,
318
00:24:32,840 --> 00:24:35,040
there are other conversations
to be had.
319
00:24:35,040 --> 00:24:37,160
HE IMITATES BIRD
320
00:24:40,520 --> 00:24:43,840
Nobody knows why it happens,
321
00:24:43,840 --> 00:24:46,160
but when you make strange noises
here,
322
00:24:46,160 --> 00:24:48,840
seabirds fall from the sky.
323
00:24:49,920 --> 00:24:52,960
HE IMITATES BIRD
324
00:24:54,520 --> 00:24:57,040
HE IMITATES BIRD
325
00:25:05,200 --> 00:25:06,960
And in Florida,
326
00:25:06,960 --> 00:25:11,800
you can get little lizards
to reply to a mirror.
327
00:25:11,800 --> 00:25:14,920
And there, that's it.
328
00:25:14,920 --> 00:25:17,240
The full works.
329
00:25:20,520 --> 00:25:23,560
All those signals are fairly simple,
330
00:25:23,560 --> 00:25:28,120
but by the 1990s, long-term studies
were showing that some monkeys
331
00:25:28,120 --> 00:25:31,480
even have the beginnings
of a vocabulary.
332
00:25:33,760 --> 00:25:37,840
At dawn, vervet monkeys
come down from the trees
333
00:25:37,840 --> 00:25:40,520
to search for food on the ground.
334
00:25:43,120 --> 00:25:45,720
Down here, of course,
they are much more vulnerable
335
00:25:45,720 --> 00:25:50,040
than they were up in the trees, but
there's always a sentinel on watch.
336
00:25:55,760 --> 00:25:58,360
A python.
337
00:25:58,360 --> 00:26:01,400
The sentinel gives a call
which means snake.
338
00:26:01,400 --> 00:26:05,040
MONKEY CHATTERS
339
00:26:11,000 --> 00:26:14,400
The meaning is very precise and
is only made when a snake appears.
340
00:26:14,400 --> 00:26:18,360
It could be called a word
and when other vervets hear it,
341
00:26:18,360 --> 00:26:20,640
they know exactly
what the danger is.
342
00:26:24,560 --> 00:26:29,040
Calls and such specific meanings
are very rare in the animal world,
343
00:26:29,040 --> 00:26:32,120
but vervets have developed
several of them.
344
00:26:37,440 --> 00:26:40,120
A call that means danger
from the air.
345
00:26:41,440 --> 00:26:43,880
And the vervets run
into the denser branches
346
00:26:43,880 --> 00:26:47,920
where the eagle won't pursue them
for fear of damaging its wings.
347
00:26:53,720 --> 00:26:57,000
From the safety
of the thorny branches,
348
00:26:57,000 --> 00:27:00,320
the vervets scream furiously
and one is even brave enough
349
00:27:00,320 --> 00:27:02,720
to launch a lightening attack.
350
00:27:10,920 --> 00:27:14,440
Communication between males
and females of a species,
351
00:27:14,440 --> 00:27:17,840
not only by sound,
but by visual signals,
352
00:27:17,840 --> 00:27:20,720
has, of course,
long fascinated naturalists,
353
00:27:20,720 --> 00:27:23,000
particularly in the 19th century.
354
00:27:24,200 --> 00:27:26,600
When I was a boy of about nine,
355
00:27:26,600 --> 00:27:31,160
I read a book that thrilled me
to the core. This is it.
356
00:27:31,160 --> 00:27:33,840
It's called the Malay Archipelago,
357
00:27:33,840 --> 00:27:37,800
The Land of the Orang-utan
and The Bird of Paradise,
358
00:27:37,800 --> 00:27:41,080
by Alfred Russel Wallace.
359
00:27:41,080 --> 00:27:45,480
It contained one particularly
exciting illustration,
360
00:27:45,480 --> 00:27:49,080
this is it,
it shows native tribes' people
361
00:27:49,080 --> 00:27:53,000
hunting birds of paradise,
which are displaying in the tree.
362
00:27:53,000 --> 00:27:55,880
And I dreamt that sometime
363
00:27:55,880 --> 00:28:00,000
I might get there to see it
for myself.
364
00:28:00,000 --> 00:28:02,880
Well, in 1957, I did.
365
00:28:07,120 --> 00:28:09,840
From the capital of New Guinea,
Port Moresby,
366
00:28:09,840 --> 00:28:11,400
we chartered a plane
367
00:28:11,400 --> 00:28:12,480
and flew inland,
368
00:28:12,480 --> 00:28:16,520
heading for territory that was still
regarded as being pretty wild.
369
00:28:16,520 --> 00:28:19,520
After an hour's flight,
we were nearing the middle
370
00:28:19,520 --> 00:28:21,600
of the mountains when suddenly,
371
00:28:21,600 --> 00:28:26,160
we saw a wide, fertile valley,
ringed with mountains.
372
00:28:26,160 --> 00:28:29,240
This was our destination, the place
in which we planned to work
373
00:28:29,240 --> 00:28:33,000
for the next few months,
the valley of the Waghi River.
374
00:28:35,000 --> 00:28:38,480
The Waghi people knew about
birds of paradise all right!
375
00:28:38,480 --> 00:28:40,440
They used their plumes as money
376
00:28:40,440 --> 00:28:44,640
and they were essential elements
in all important transactions.
377
00:28:48,320 --> 00:28:50,560
I watched a ceremonial dance
378
00:28:50,560 --> 00:28:52,920
in which each man
had decorated himself
379
00:28:52,920 --> 00:28:57,440
with the plumes of at least
30 birds of paradise.
380
00:28:57,440 --> 00:29:01,040
Here, I was looking at the remains
of 20,000 dead birds.
381
00:29:01,040 --> 00:29:03,720
They were clearly so keenly hunted,
382
00:29:03,720 --> 00:29:06,440
we stood little chance
of finding them here.
383
00:29:08,280 --> 00:29:11,040
So, cameraman Charles Lagus and I
384
00:29:11,040 --> 00:29:14,360
decided to go into wilder country
to the north.
385
00:29:16,240 --> 00:29:18,920
It was hard walking, but when
we reached the top of the ridge
386
00:29:18,920 --> 00:29:22,360
that formed the wall of the valley,
we ran into trouble.
387
00:29:22,360 --> 00:29:27,040
I found, to my horror, that the men
were refusing to go any further.
388
00:29:27,040 --> 00:29:32,680
They told me firmly that this was
the end of their tribal frontier.
389
00:29:32,680 --> 00:29:35,240
I thought we weren't paying them
enough so I thought,
390
00:29:35,240 --> 00:29:38,720
another cake of salt all round,
that'll be all right.
391
00:29:38,720 --> 00:29:43,880
But no, it turned out that they said
the people who lived beyond there
392
00:29:43,880 --> 00:29:48,400
were bad men,
they eat people, they said,
393
00:29:48,400 --> 00:29:49,960
we won't go there.
394
00:29:49,960 --> 00:29:54,440
And I said, "Come along, lads,
we can manage this."
395
00:29:54,440 --> 00:29:57,200
When suddenly
I noticed a white feather
396
00:29:57,200 --> 00:29:58,520
flickering behind a boulder
397
00:29:58,520 --> 00:30:00,840
and I looked and there was
another one behind a tree
398
00:30:00,840 --> 00:30:03,040
and while I was wondering
what this meant,
399
00:30:03,040 --> 00:30:05,960
suddenly these men
leapt out of hiding
400
00:30:05,960 --> 00:30:08,880
and came charging down the path
towards us,
401
00:30:08,880 --> 00:30:11,320
waving stone axes and spears
402
00:30:11,320 --> 00:30:14,480
and I simply couldn't think
of what to do
403
00:30:14,480 --> 00:30:17,080
except to go towards them
404
00:30:17,080 --> 00:30:20,120
and stick out my hand and said,
"Good afternoon".
405
00:30:21,080 --> 00:30:25,640
And to my astonishment, they seized
my hand, pumped it up and down,
406
00:30:25,640 --> 00:30:27,080
and said, "Good afternoon."
407
00:30:28,840 --> 00:30:31,840
And it turned out that the reason
was that this tribal frontier
408
00:30:31,840 --> 00:30:36,840
was where, when the two people met,
they made sure the other person
409
00:30:36,840 --> 00:30:40,200
thought they were still warlike
and tough, because if they didn't,
410
00:30:40,200 --> 00:30:42,880
and appeared to be
soft and peaceable,
411
00:30:42,880 --> 00:30:46,240
obviously they were
ready for a bit of rape and pillage.
412
00:30:46,240 --> 00:30:50,200
So whenever to people met,
they always looked ferocious.
413
00:30:50,200 --> 00:30:51,880
It certainly convinced me.
414
00:30:54,160 --> 00:30:55,520
Much relieved, we carried on.
415
00:30:57,480 --> 00:31:00,640
We heard calls of birds of paradise,
but we just couldn't find a place
416
00:31:00,640 --> 00:31:02,480
where we could film them.
417
00:31:04,280 --> 00:31:09,120
And then, after three weeks, one
morning at dawn, our luck changed.
418
00:31:10,520 --> 00:31:14,040
Low-down, in a tree,
a plumed bird of paradise.
419
00:31:14,040 --> 00:31:16,200
And there, his unplumed female.
420
00:31:17,400 --> 00:31:20,840
As far as I knew,
this was the first film
421
00:31:20,840 --> 00:31:24,120
ever taken of a bird of paradise
displaying in the wild.
422
00:31:26,160 --> 00:31:28,760
The pictures were OK,
as far as they went.
423
00:31:28,760 --> 00:31:32,040
But Charles's camera
was an old clockwork one,
424
00:31:32,040 --> 00:31:34,000
and it made a noise
like a cement mixer,
425
00:31:34,000 --> 00:31:39,000
so I couldn't record the sound
while he was filming.
426
00:31:39,000 --> 00:31:41,000
But when he had finished,
427
00:31:41,000 --> 00:31:44,120
I turned on the recorder
and I got two sets of calls,
428
00:31:44,120 --> 00:31:45,960
one which went "wah-wah"
with two,
429
00:31:45,960 --> 00:31:48,240
and one, "wah-wah-wah",
with three.
430
00:31:48,240 --> 00:31:51,440
And when we came back I joined
the two together so they ran
431
00:31:51,440 --> 00:31:54,440
and we could play it
throughout the display.
432
00:32:00,760 --> 00:32:03,120
And after the show had gone out,
I got a letter from my old
433
00:32:03,120 --> 00:32:06,600
professor of zoology, and he said,
"Many congratulations on this
434
00:32:06,600 --> 00:32:10,720
wonderful documentation
of bird of paradise displays.
435
00:32:10,720 --> 00:32:16,280
But had I noticed that, in fact,
this bird did its two-note call
436
00:32:16,280 --> 00:32:19,640
and then its three-note call,
alternating, never two together,
437
00:32:19,640 --> 00:32:21,080
then three together.
438
00:32:21,080 --> 00:32:24,080
Would I perhaps write
a learned paper
439
00:32:24,080 --> 00:32:26,840
about this strange phenomenon?"
440
00:32:26,840 --> 00:32:29,360
I had to explain to him
that, actually,
441
00:32:29,360 --> 00:32:33,240
it was a limitation of
early natural history photography.
442
00:32:33,240 --> 00:32:38,040
But the pictures produced
by our primitive equipment
443
00:32:38,040 --> 00:32:42,240
were black-and-white and fuzzy,
so 40 years later, I made another
444
00:32:42,240 --> 00:32:45,760
attempt to film the birds that
Wallace had described so vividly.
445
00:32:45,760 --> 00:32:47,960
As far as I know,
446
00:32:47,960 --> 00:32:51,400
Wallace wasn't able to climb
the tree to get a closer view
447
00:32:51,400 --> 00:32:55,440
of the birds, but these days we have
ways of doing so relatively simply.
448
00:32:57,320 --> 00:33:01,160
You fire a thin line with
a catapult over one of those higher
449
00:33:01,160 --> 00:33:05,320
branches, haul up a thicker rope,
attach a system of counterweights,
450
00:33:05,320 --> 00:33:08,600
and all you have to do is clip
yourself on and off you go.
451
00:33:22,800 --> 00:33:24,680
And here's the top.
452
00:33:28,640 --> 00:33:32,320
The birds are in another emergent
tree, just like this one,
453
00:33:32,320 --> 00:33:36,000
and I've got an absolutely
clear view of them.
454
00:33:40,040 --> 00:33:42,960
This, at last,
is Wallace's picture come to life.
455
00:33:42,960 --> 00:33:46,760
He was the first European to glimpse
this extraordinary spectacle,
456
00:33:46,760 --> 00:33:49,880
and he knew well, in general terms,
what was happening.
457
00:33:49,880 --> 00:33:52,840
This is a female,
and she has come to pick
458
00:33:52,840 --> 00:33:56,600
a mate from among the gorgeous males
who are displaying.
459
00:34:01,720 --> 00:34:04,800
The female has hopped on to
the perch of the male of her choice,
460
00:34:04,800 --> 00:34:07,560
that's a straight invitation
to mate.
461
00:34:11,000 --> 00:34:12,800
This is all he does as a father.
462
00:34:14,760 --> 00:34:18,040
Now she'll fly away
and raise her young unaided.
463
00:34:20,000 --> 00:34:22,480
The females are comparatively drab.
464
00:34:22,480 --> 00:34:25,000
It's only the male
that have extravagant plumes.
465
00:34:28,800 --> 00:34:31,480
Each of the 40 of species
has its own kind.
466
00:34:31,480 --> 00:34:33,520
Growing them and displaying them
467
00:34:33,520 --> 00:34:35,800
must take a huge
amount of a male's energy.
468
00:34:41,400 --> 00:34:45,520
Can it really be worth all this
just to mate with a female?
469
00:34:50,960 --> 00:34:53,320
Well, it seems that it is.
470
00:34:53,320 --> 00:34:57,160
At least for the male who puts
on the most impressive performance,
471
00:34:57,160 --> 00:35:00,040
for he will mate with virtually
all the females in the area.
472
00:35:08,280 --> 00:35:11,720
So, generation after generation,
it is
473
00:35:11,720 --> 00:35:14,360
only the winner
whose genes are passed on,
474
00:35:14,360 --> 00:35:17,160
and it is this,
over many generations,
475
00:35:17,160 --> 00:35:20,680
that produces such great
extravagance of plumage and display.
476
00:35:23,320 --> 00:35:25,680
It's a process known
as sexual selection.
477
00:35:33,080 --> 00:35:35,560
The males of another
family of New Guinea birds
478
00:35:35,560 --> 00:35:38,560
impress their females not with
feathers, but with brightly
479
00:35:38,560 --> 00:35:42,640
coloured objects, which they collect
and display in bowers.
480
00:35:44,920 --> 00:35:48,360
And this is the work of
the master builder among bowerbirds.
481
00:35:51,400 --> 00:35:54,520
I'm in the Vogelkop on
the far western tip of New Guinea,
482
00:35:54,520 --> 00:35:57,320
and this is the bower
of the Vogelkop bowerbird.
483
00:35:59,360 --> 00:36:02,000
And what an astonishment it is,
484
00:36:02,000 --> 00:36:04,280
surely one of the wonders
of the natural world.
485
00:36:04,280 --> 00:36:08,040
The bower has been
completely roofed over.
486
00:36:08,040 --> 00:36:12,240
Their orange fruit,
these glowing orange dead leaves,
487
00:36:12,240 --> 00:36:16,280
and behind me there are black fruits
488
00:36:16,280 --> 00:36:18,960
All of which has been bought
specially by the bird.
489
00:36:36,520 --> 00:36:42,040
A further step in our understanding
of such spectacular behaviour
490
00:36:42,040 --> 00:36:46,480
came in 1976 when Richard Dawkins
published this book,
491
00:36:46,480 --> 00:36:48,000
The Selfish Gene.
492
00:36:48,000 --> 00:36:54,600
In it he brings together evolution,
genetics and animal behaviour,
493
00:36:54,600 --> 00:36:59,000
and argues that it is that the gene
that drives evolution.
494
00:37:00,120 --> 00:37:05,000
The survival of an individual animal
is of less importance
495
00:37:05,000 --> 00:37:06,600
than the survival of its genes.
496
00:37:08,080 --> 00:37:11,960
And thinking about selection
at the level of the gene
497
00:37:11,960 --> 00:37:15,960
also enables us to understand
why it is that some animals,
498
00:37:15,960 --> 00:37:19,400
sometimes,
behave in an unselfish way.
499
00:37:25,760 --> 00:37:29,640
These ants are all female.
And they are prepared... Ow!
500
00:37:29,640 --> 00:37:34,000
They're prepared to attack me
in defence of their colony
501
00:37:34,000 --> 00:37:38,000
and to die in the process, because
the genes that they carry are
502
00:37:38,000 --> 00:37:43,160
the same as their sister workers
and indeed, their mothers.
503
00:37:43,160 --> 00:37:48,560
So in attacking me they are,
in fact, doing their best to help
504
00:37:48,560 --> 00:37:51,840
ensure that their genes are passed
to the next generation.
505
00:37:51,840 --> 00:37:55,840
You don't have to breed yourself
to pass on your own genes.
506
00:37:55,840 --> 00:38:00,760
All the female worker and soldier
ants in this nest are sisters,
507
00:38:00,760 --> 00:38:03,320
and they share 75% of their genes.
508
00:38:03,320 --> 00:38:08,600
So the colony acts as a kind of
single super-organism,
509
00:38:08,600 --> 00:38:11,240
and, amazingly, it was discovered
that some mammals
510
00:38:11,240 --> 00:38:12,920
live in a similar kind of community.
511
00:38:17,200 --> 00:38:20,800
Meerkats in the Kalahari Desert.
512
00:38:22,120 --> 00:38:25,160
They spend the night in burrows,
513
00:38:25,160 --> 00:38:29,160
they find all the food
they need on the ground.
514
00:38:29,160 --> 00:38:32,520
They are swift and expert runners.
515
00:38:32,520 --> 00:38:35,640
But, oddly enough, they also climb,
516
00:38:35,640 --> 00:38:39,720
and they have very good reasons
for doing so.
517
00:38:39,720 --> 00:38:44,440
But, first of all, they have to
warm up in the early morning sun.
518
00:38:51,440 --> 00:38:55,000
They live in groups in which
the only dominant pair breeds,
519
00:38:55,000 --> 00:38:58,200
and some of their offspring,
even when adult, do not breed
520
00:38:58,200 --> 00:39:01,280
but stay around to help rear
the young.
521
00:39:05,480 --> 00:39:08,880
While one helper watches out for
danger, another catches a scorpion
522
00:39:08,880 --> 00:39:11,600
and encourages one of the youngsters
to eat it.
523
00:39:18,880 --> 00:39:21,840
These helpers appear to be
very unselfish,
524
00:39:21,840 --> 00:39:25,440
but they're acting this way,
probably because
they share the same genes
525
00:39:25,440 --> 00:39:28,680
as their charges
and by helping them,
526
00:39:28,680 --> 00:39:33,080
they're ensuring the transmission of
those genes to the next generation.
527
00:39:35,440 --> 00:39:38,080
The first meerkat film we made
turned these animals
528
00:39:38,080 --> 00:39:43,120
into stars, not, I must admit,
because of their selfish genes,
529
00:39:43,120 --> 00:39:46,040
but because
of their enchanting personalities.
530
00:40:04,720 --> 00:40:07,680
The factors that make these animals
behave in the way they do
531
00:40:07,680 --> 00:40:11,640
are transmitted in their genes.
532
00:40:11,640 --> 00:40:14,640
But what kind of physical structure
533
00:40:14,640 --> 00:40:17,280
could carry all this information?
534
00:40:17,280 --> 00:40:19,760
That was one of the great puzzles
535
00:40:19,760 --> 00:40:22,160
that had intrigued geneticists
ever since
536
00:40:22,160 --> 00:40:26,280
the beginnings of their science
a century ago.
537
00:40:26,280 --> 00:40:30,400
But that mystery too
was about to be solved.
538
00:40:30,400 --> 00:40:33,880
In 1953, here
in the Cavendish Laboratories,
539
00:40:33,880 --> 00:40:38,040
two young researchers,
Francis Crick and James Watson
540
00:40:38,040 --> 00:40:41,880
were building models like this.
541
00:40:41,880 --> 00:40:46,560
It was their way of thinking about
and investigating the structure
542
00:40:46,560 --> 00:40:51,080
of a complex molecule that's found
in the genes of all animals,
543
00:40:51,080 --> 00:40:53,560
DNA.
544
00:40:53,560 --> 00:40:56,680
The crucial bit are these chains
545
00:40:56,680 --> 00:41:00,720
which encircle the rod, one...
546
00:41:00,720 --> 00:41:06,000
and here is the second
and entwine.
547
00:41:06,000 --> 00:41:09,320
This is the double helix.
548
00:41:09,320 --> 00:41:13,240
An extraordinary feat
of intellectual deduction.
549
00:41:13,240 --> 00:41:16,200
And it led to a whole new branch
of science,
550
00:41:16,200 --> 00:41:18,200
molecular genetics.
551
00:41:18,200 --> 00:41:22,560
More recently, DNA has given us
new insights
552
00:41:22,560 --> 00:41:25,800
into the family relationship
of animals
553
00:41:25,800 --> 00:41:29,520
using a technique
called DNA finger-printing.
554
00:41:29,520 --> 00:41:32,120
It was developed
by Sir Alec Jeffreys
555
00:41:32,120 --> 00:41:34,840
of Leicester University in 1984.
556
00:41:34,840 --> 00:41:38,520
And using just a simple smear
of blood it's possible not only
557
00:41:38,520 --> 00:41:41,240
to identify one
particular individual,
558
00:41:41,240 --> 00:41:45,040
but to establish whether or not
it's closely related to another.
559
00:41:46,120 --> 00:41:48,240
For example, we used to think
560
00:41:48,240 --> 00:41:51,200
that most birds lived
in straightforward pairs.
561
00:41:51,200 --> 00:41:53,920
We watched them courting and mating
562
00:41:53,920 --> 00:41:56,720
and rearing their young
and so we assumed
563
00:41:56,720 --> 00:41:59,960
that they were faithful
to one another.
564
00:41:59,960 --> 00:42:03,120
But DNA fingerprinting showed us
how wrong we were.
565
00:42:03,120 --> 00:42:06,560
As I explained in The Life of Birds.
566
00:42:06,560 --> 00:42:08,200
Perhaps the most
567
00:42:08,200 --> 00:42:10,200
bizarre behaviour of all
568
00:42:10,200 --> 00:42:14,040
takes place in the suburban gardens
of England.
569
00:42:14,040 --> 00:42:19,280
And it seems that until very
recently, nobody even noticed.
570
00:42:20,360 --> 00:42:24,640
A young female hedge sparrow,
a dunnock, ready to lay.
571
00:42:25,600 --> 00:42:27,600
This is her mate, Alpha,
572
00:42:27,600 --> 00:42:30,840
singing lustily, declaring his
ownership of the nest
573
00:42:30,840 --> 00:42:34,160
and the territory around it
from which he gathers food.
574
00:42:36,880 --> 00:42:42,120
The pair often feed together, a
devoted couple if ever you saw one.
575
00:42:45,000 --> 00:42:48,000
He seldom lets her out of his sight,
576
00:42:48,000 --> 00:42:51,600
but she is not as faithful
as she might be...
577
00:42:53,840 --> 00:42:55,880
There's a third bird around,
578
00:42:55,880 --> 00:42:59,440
Beta, another younger male.
579
00:42:59,440 --> 00:43:04,760
He's not popular with Alpha
and they're continually squabbling.
580
00:43:05,920 --> 00:43:10,240
Sometimes the fights can get
quite vicious and feathers fly.
581
00:43:11,240 --> 00:43:15,160
But in spite of that,
Beta stays around,
582
00:43:15,160 --> 00:43:17,640
skulking in the hedge.
583
00:43:20,160 --> 00:43:24,280
Alpha, it seems, has the female
to himself once more.
584
00:43:25,680 --> 00:43:28,800
But she has got her eye cocked.
585
00:43:28,800 --> 00:43:33,080
Beta is still in the hedge,
calling quietly to her.
586
00:43:36,640 --> 00:43:38,600
She joins him.
587
00:43:38,600 --> 00:43:42,760
And now, while Alpha
is preoccupied with feeding,
588
00:43:42,760 --> 00:43:45,200
she and Beta get together.
589
00:43:45,200 --> 00:43:49,560
Twirling her tail is an invitation
and, in a split second, they mate.
590
00:43:55,840 --> 00:43:57,760
Beta flies away.
591
00:43:59,000 --> 00:44:01,360
But now, out in the open,
592
00:44:01,360 --> 00:44:05,240
she is courting Alpha
with that same old tail twirling.
593
00:44:05,240 --> 00:44:07,640
And now, he mates with her.
594
00:44:14,080 --> 00:44:16,880
She has kept two males happy,
595
00:44:16,880 --> 00:44:20,320
both of whom will help to feed
the young when they hatch.
596
00:44:23,400 --> 00:44:26,040
DNA fingerprinting
has now revealed
597
00:44:26,040 --> 00:44:30,800
that only about a fifth
of the apparently monogamous birds
598
00:44:30,800 --> 00:44:34,640
are actually genuinely faithful
to one another.
599
00:44:35,800 --> 00:44:38,640
Molecular genetics combined
with long-term studies
600
00:44:38,640 --> 00:44:41,800
of animals in the wild
have challenged our preconceptions
601
00:44:41,800 --> 00:44:45,040
about how animals live their lives.
602
00:44:46,120 --> 00:44:49,480
And there are also long-term studies
that have shed light
603
00:44:49,480 --> 00:44:52,880
on our own evolution and ancestry,
604
00:44:52,880 --> 00:44:56,320
in particular,
those by Jane Goodall,
605
00:44:56,320 --> 00:45:01,480
who started her work in 1960
in Tanzania on chimps.
606
00:45:04,600 --> 00:45:08,080
The 26-year-old Jane Goodall
arrived in Africa
607
00:45:08,080 --> 00:45:10,080
with no scientific training
608
00:45:10,080 --> 00:45:13,800
and had to patiently follow
the chimps for two years
609
00:45:13,800 --> 00:45:17,200
before they allowed her
to get close to them.
610
00:45:21,280 --> 00:45:22,800
In order to identify them,
611
00:45:22,800 --> 00:45:25,920
she gave them the sort of names
we use for one another,
612
00:45:25,920 --> 00:45:29,560
which got her into a lot of trouble
with more conventional scientists,
613
00:45:29,560 --> 00:45:33,560
who accused her of crediting her
animals with human characteristics,
614
00:45:33,560 --> 00:45:35,800
for which there was no evidence.
615
00:45:38,600 --> 00:45:41,720
But she made some
revolutionary discoveries,
616
00:45:41,720 --> 00:45:44,120
including proving that
chimps use tools
617
00:45:44,120 --> 00:45:46,880
and even modify them
for particular purposes.
618
00:45:49,840 --> 00:45:52,200
They fish for termites with twigs,
619
00:45:52,200 --> 00:45:55,640
which they make more effective
by stripping off the leaves.
620
00:46:01,560 --> 00:46:05,320
Manufacturing tools in such a way
had, until then,
621
00:46:05,320 --> 00:46:08,360
been thought to be something that
only human beings could do.
622
00:46:11,320 --> 00:46:13,600
But in the late 1970s,
623
00:46:13,600 --> 00:46:17,120
chimps on the other side
of the continent, in West Africa,
624
00:46:17,120 --> 00:46:21,240
were discovered using
different tools in a different way.
625
00:46:22,920 --> 00:46:25,320
Placing the nuts in a hole
in the root,
626
00:46:25,320 --> 00:46:28,480
they crack them open
with specially selected hammers.
627
00:46:32,360 --> 00:46:35,200
Repeated use has deepened the hole
628
00:46:35,200 --> 00:46:38,400
and produced an anvil,
which holds the nut in place.
629
00:46:42,320 --> 00:46:47,440
Using these tools, experienced
chimps can crack two nuts a minute.
630
00:46:51,600 --> 00:46:56,600
For the hardest nuts, they keep
and transport rare stone hammers.
631
00:46:59,360 --> 00:47:01,880
Cracking is not easy.
632
00:47:01,880 --> 00:47:04,880
You have to choose
both a good anvil...
633
00:47:06,240 --> 00:47:07,640
..and a good hammer.
634
00:47:16,000 --> 00:47:20,920
Only West African chimpanzees have
developed this nut-cracking ability,
635
00:47:20,920 --> 00:47:24,520
and it takes more than ten years
to learn the technique.
636
00:47:30,120 --> 00:47:34,960
It's now known that chimps use
up to 20 different types of tools.
637
00:47:37,000 --> 00:47:40,240
Nut-cracking was first
discovered by Christophe Boesch,
638
00:47:40,240 --> 00:47:43,840
who had been studying these chimps
since 1976.
639
00:47:45,240 --> 00:47:49,560
And in 1989, I went out to
the Ivory Coast to visit him.
640
00:47:50,800 --> 00:47:54,800
How did you manage to get these
animals so accustomed to you,
641
00:47:54,800 --> 00:47:57,560
so that we could stand as
close to them as this?
642
00:47:59,240 --> 00:48:01,240
Oh, just patience.
643
00:48:01,240 --> 00:48:03,960
It took us five years. Five years?
644
00:48:03,960 --> 00:48:07,480
Five years, just following them,
being always very quiet,
645
00:48:07,480 --> 00:48:11,920
never aggressive,
always the same colours and clothes
646
00:48:11,920 --> 00:48:13,280
and patience, patience.
647
00:48:15,280 --> 00:48:18,080
But Christophe wasn't entirely sure
648
00:48:18,080 --> 00:48:21,160
that he wanted a 63-year-old
with him in the forest.
649
00:48:21,160 --> 00:48:23,400
IN FRENCH ACCENT:
"Who is this old man?", he said,
650
00:48:23,400 --> 00:48:25,200
"Who is this old man
who want to come?"
651
00:48:25,200 --> 00:48:27,480
"Is he fit? Can he run?"
652
00:48:27,480 --> 00:48:29,800
The answer to those was no,
on both,
653
00:48:29,800 --> 00:48:32,240
but, nonetheless,
I managed to get there.
654
00:48:32,240 --> 00:48:36,200
And his technique was that he would
travel with them all day,
655
00:48:36,200 --> 00:48:39,360
wherever they went,
and when they moved, he moved.
656
00:48:39,360 --> 00:48:42,520
And he didn't leave them until
they had made their nests at night.
657
00:48:43,640 --> 00:48:47,120
And only then would
he go back to his camp,
658
00:48:47,120 --> 00:48:49,800
but then get up at four o'clock
the next morning
659
00:48:49,800 --> 00:48:52,080
in order to run back there
and sketch them
660
00:48:52,080 --> 00:48:53,680
before they went off again.
661
00:48:53,680 --> 00:48:56,520
And he was...
Christophe was quite right...
662
00:48:56,520 --> 00:49:00,400
I mean, it's hugely demanding. I've
never been so tired in all my life.
663
00:49:02,040 --> 00:49:05,280
But Christophe had also discovered
a darker side
664
00:49:05,280 --> 00:49:07,040
to chimps' personalities.
665
00:49:08,880 --> 00:49:12,840
You don't normally think
of them as hunters.
666
00:49:12,840 --> 00:49:16,160
More as...gentle vegetarians,
667
00:49:16,160 --> 00:49:19,120
munching fruit and picking leaves.
668
00:49:19,120 --> 00:49:23,320
But if you follow them for any
length of time in their true home,
669
00:49:23,320 --> 00:49:26,320
these forests in West Africa,
670
00:49:26,320 --> 00:49:29,040
you discover that they ARE hunters.
671
00:49:29,040 --> 00:49:32,200
What's more, they hunt in teams
672
00:49:32,200 --> 00:49:37,840
and have a more complex strategy
than any other hunting animal
673
00:49:37,840 --> 00:49:39,000
except...
674
00:49:39,000 --> 00:49:41,200
CHIMP SCREECHES LOUDLY
675
00:49:41,200 --> 00:49:43,160
..except, of course...
676
00:49:43,160 --> 00:49:44,400
man.
677
00:49:48,480 --> 00:49:51,440
The technique they will
almost certainly use
678
00:49:51,440 --> 00:49:56,560
is that one of them will be driving
the Colobus ahead of him
679
00:49:56,560 --> 00:50:00,600
and there will be others that go
up on either side, who are blockers,
680
00:50:00,600 --> 00:50:03,000
who won't make any attempt
to catch the monkeys,
681
00:50:03,000 --> 00:50:06,800
and then there are chasers, who go
and grab at the monkey if they can
682
00:50:06,800 --> 00:50:12,880
and, finally, there's one male
who will go up ahead and ambush it.
683
00:50:12,880 --> 00:50:15,280
So, bringing the whole trap closed.
684
00:50:17,400 --> 00:50:19,800
The monkeys are now getting alarmed.
685
00:50:21,720 --> 00:50:24,840
A driver's going up,
to prevent the group from settling
686
00:50:24,840 --> 00:50:29,200
and to drive them towards an area
where they're more easily trapped.
687
00:50:29,200 --> 00:50:31,840
Now, it looks as though
they're all in position.
688
00:50:31,840 --> 00:50:34,880
The drivers have gone up,
the blockers have gone up and now,
689
00:50:34,880 --> 00:50:38,560
the one who's going to make
the ambush and close the ring,
690
00:50:38,560 --> 00:50:39,760
he's gone up too.
691
00:50:39,760 --> 00:50:43,320
The Colobus will be very lucky
if they escape now.
692
00:50:43,320 --> 00:50:45,480
RUSTLING
693
00:50:47,600 --> 00:50:49,760
MONKEYS SCREECH
694
00:50:54,800 --> 00:50:56,520
They've got one!
695
00:51:02,280 --> 00:51:04,920
And now, the kill is brought down,
696
00:51:04,920 --> 00:51:08,000
so that the females
and others can share it.
697
00:51:12,800 --> 00:51:15,360
And there's the reward
for that long chase.
698
00:51:16,360 --> 00:51:18,680
The divided body
of a Colobus monkey.
699
00:51:19,960 --> 00:51:21,600
These...
700
00:51:21,600 --> 00:51:23,280
blood-stained faces...
701
00:51:23,280 --> 00:51:26,520
may well horrify us.
702
00:51:26,520 --> 00:51:29,360
But we might also see in them
703
00:51:29,360 --> 00:51:33,600
the face of our long-distant
hunting ancestors.
704
00:51:34,680 --> 00:51:36,400
And if we are...
705
00:51:36,400 --> 00:51:38,360
appalled...
706
00:51:38,360 --> 00:51:41,360
by that mob violence
and blood lust,
707
00:51:41,360 --> 00:51:44,080
we might also see
in that too, perhaps,
708
00:51:44,080 --> 00:51:48,000
the origins of the teamwork...
709
00:51:48,000 --> 00:51:49,560
that have, in the end,
710
00:51:49,560 --> 00:51:53,200
brought human beings
many of their greatest triumphs.
711
00:51:59,480 --> 00:52:02,520
But the studies of chimpanzees
712
00:52:02,520 --> 00:52:06,240
started by Jane Goodall, continued
by Christophe Boesch and others
713
00:52:06,240 --> 00:52:08,040
have shown us something else.
714
00:52:09,080 --> 00:52:11,800
It's not just that chimpanzees
are capable
715
00:52:11,800 --> 00:52:15,880
of developing their own techniques
for hunting or tool-making,
716
00:52:15,880 --> 00:52:18,520
but that each community of chimps
717
00:52:18,520 --> 00:52:22,000
is capable of developing
its own version.
718
00:52:22,000 --> 00:52:28,000
In other words, chimpanzees'
communities have their own cultures.
719
00:52:28,000 --> 00:52:32,120
And that was thought to be something
that was uniquely human.
720
00:52:32,120 --> 00:52:36,920
Everyone knew, of course, that
chimps are our biological cousins,
721
00:52:36,920 --> 00:52:40,080
but it's only in the last 20 years
that we've discovered
722
00:52:40,080 --> 00:52:45,040
that we share of about 95%
of our DNA with them.
723
00:52:45,040 --> 00:52:48,160
And that's because we now have
the tools to find out
724
00:52:48,160 --> 00:52:50,880
exactly how closely
we are all related.
725
00:52:55,920 --> 00:52:59,320
In 1990, scientists in 20 labs
around the world
726
00:52:59,320 --> 00:53:05,160
set out to identify all the 3,000
million separate chemical units
727
00:53:05,160 --> 00:53:07,200
that make up the human genetic code.
728
00:53:12,440 --> 00:53:14,120
It took nearly 13 years, and then,
729
00:53:14,120 --> 00:53:17,840
exactly 50 years after Crick
and Watson had worked out
730
00:53:17,840 --> 00:53:19,800
the structure of DNA,
731
00:53:19,800 --> 00:53:22,880
the human genome was cracked.
732
00:53:22,880 --> 00:53:24,520
And this is it.
733
00:53:32,680 --> 00:53:36,040
In these volumes is
all the information needed
734
00:53:36,040 --> 00:53:39,960
to define the genetic structure
of the human species.
735
00:53:41,040 --> 00:53:45,120
Each number refers to
one of our 23 chromosomes.
736
00:53:56,160 --> 00:53:58,080
If I open it up,
737
00:53:58,080 --> 00:54:01,600
you can see that
the text consists of
738
00:54:01,600 --> 00:54:07,400
just one very, very, very long list
of just four letters...
739
00:54:07,400 --> 00:54:09,880
A, C, T, G.
740
00:54:09,880 --> 00:54:12,760
Each combination represents
instructions
741
00:54:12,760 --> 00:54:16,320
for one element in the human design.
742
00:54:16,320 --> 00:54:20,440
This is the secret language of DNA.
743
00:54:20,440 --> 00:54:22,120
This is the book of life.
744
00:54:24,600 --> 00:54:28,160
And each one of us
has our own edition.
745
00:54:47,120 --> 00:54:49,280
When I first heard, back in 1953,
746
00:54:49,280 --> 00:54:52,240
that the structure of DNA
had been worked out,
747
00:54:52,240 --> 00:54:56,000
I could scarcely have imagined
that it would ever be possible
748
00:54:56,000 --> 00:54:59,240
to print out the whole
of one genome in a book.
749
00:54:59,240 --> 00:55:02,560
But, today, the process
has been so speeded up,
750
00:55:02,560 --> 00:55:06,440
that it's possible for anyone
to have it done in half a day.
751
00:55:07,800 --> 00:55:12,440
And the comparison between the
genome of one species and another
752
00:55:12,440 --> 00:55:14,440
has proved very revealing.
753
00:55:16,040 --> 00:55:18,360
The hot chemical springs
of Yellowstone
754
00:55:18,360 --> 00:55:23,080
contain the very simplest form
of life, single-celled bacteria,
755
00:55:23,080 --> 00:55:26,320
about as far removed
from our complex selves
756
00:55:26,320 --> 00:55:28,320
as any organism could be.
757
00:55:30,680 --> 00:55:36,520
But we share some 200 of our genes
with those very early life forms.
758
00:55:36,520 --> 00:55:38,480
Indeed, there are some genes
759
00:55:38,480 --> 00:55:42,600
that are common to every single
species of life on the planet.
760
00:55:42,600 --> 00:55:47,360
Our DNA extends in an unbroken chain
761
00:55:47,360 --> 00:55:51,720
right to the beginning of life,
4,000 million years ago.
762
00:55:51,720 --> 00:55:55,640
So, now, we can trace
our evolutionary heritage
763
00:55:55,640 --> 00:55:58,160
back through geological time.
764
00:56:00,840 --> 00:56:03,760
Back to the age of dinosaurs...
765
00:56:05,280 --> 00:56:08,000
..and further still
to the early amphibians.
766
00:56:10,720 --> 00:56:13,000
Back to the fish...
767
00:56:17,520 --> 00:56:21,080
..and the first back-boned animals.
768
00:56:24,800 --> 00:56:27,840
And further still,
to the single-celled organisms
769
00:56:27,840 --> 00:56:32,520
that were the very earliest form
of life to appear on this planet.
770
00:56:39,560 --> 00:56:43,800
So, in my lifetime, science
has solved many of the riddles
771
00:56:43,800 --> 00:56:47,200
which, 60 years ago,
seemed so baffling.
772
00:56:47,200 --> 00:56:50,520
How mountain ranges are formed.
773
00:56:50,520 --> 00:56:53,080
Why animals are distributed
in the way they are,
774
00:56:53,080 --> 00:56:55,760
and how they communicate
with one another.
775
00:56:55,760 --> 00:56:58,600
How a complex chemical molecule
776
00:56:58,600 --> 00:57:03,520
can transfer the characteristics
of one generation to the next.
777
00:57:03,520 --> 00:57:07,280
It's even shed some light
on that deepest of mysteries,
778
00:57:07,280 --> 00:57:10,000
the very origin of life.
779
00:57:10,000 --> 00:57:16,520
So, now, the natural world
makes more sense than it ever did,
780
00:57:16,520 --> 00:57:21,520
which is why studying it
is so rewarding and so delightful.
781
00:58:10,200 --> 00:58:12,280
I've lived through an era
782
00:58:12,280 --> 00:58:15,440
of extraordinary
scientific discoveries.
783
00:58:15,440 --> 00:58:17,320
But we've also, in that time,
784
00:58:17,320 --> 00:58:21,520
profoundly changed the way
we view the natural world.
785
00:58:21,520 --> 00:58:24,360
And that will be the subject
of next week's programme.
786
00:58:53,160 --> 00:58:56,400
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