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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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The discovery of imprinting,
of course,


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was more than just a boon
to film-makers.


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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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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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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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So when, in 1979, we came to make
a series called Life on Earth,


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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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But instead of a barren
volcanic landscape,


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its searchlights revealed a whole
community of hitherto-unknown


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animals that were
living in this black this.


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There were giant tube worms nearly
a metre long, and among them,


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small fish and crabs.


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But what were all these
creatures feeding on,


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so far from the energy of the sun?


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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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and the chemical compounds
they carried


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were being deposited
as great, rocky towers.


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Some of the dissolved chemicals
were serving as food for bacteria.


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The bacteria nourished the tube worm
and they, in turn,


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were food for crabs and fish.


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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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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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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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In the 19th century,
zoology was still at stage


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of collecting
and identifying species.


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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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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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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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The suspicion grew in Darwin's mind
that species were not fixed forever.


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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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The differences that Darwin
had noticed amongst these


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Galapagos animals were,
of course, more tiny.


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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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He gave the idea irresistible force
by suggesting a mechanism


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which might have bought that about.


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He called the mechanism
natural selection.


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So, Darwin had explained
how different species evolved.


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But he also proposed that all life
was inter-related,


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having come from a common origin.


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That, of course, implied
the existence of intermediate forms,


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links between
the great animal groups.


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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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Although it lives in water,
just like an ordinary fish,


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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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But the actual ancient creature
that linked fish


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and the first land-living creatures
wasn't found until very recently.


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Fossils of fish very
like these Australian lungfish


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are known from rocks
that are some 400 million years old.


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And we can be pretty sure that those
ancient fish could breathe air.


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But could they manage to get out
of the water and up onto the land?


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How could they have managed that?
Nobody could be sure.


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There was a missing link.


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And then, this turned up in 2004.


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This was found in Arctic Canada


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and was called tiktaalik.


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You see, it's about the same size
as a lungfish but it's got


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a skull which is flattened that way,
and a row of formidable teeth.


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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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and here's one of them.


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It had a fleshy base,
just like a lungfish,


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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.


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00:17:11,120 --> 00:17:15,280
So, tiktaalik probably looked
a bit like present-day amphibians,


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such as salamanders.


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00:17:16,840 --> 00:17:19,600
The link between fish and
land-living animals


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had now been found.


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Another piece in the jigsaw of life
had been put in place.


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But, 60 years ago,
there was another baffling puzzle.


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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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can occur on both sides of an ocean,


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in West Africa and South America,
for example?


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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


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floated across on rafts of
vegetation, but what about frogs?


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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,


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so they couldn't
have floated across.


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00:18:09,320 --> 00:18:14,000
But maybe it wasn't the frogs that
moved, maybe it was the continents.


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00:18:20,160 --> 00:18:23,320
That was the suggestion
that was being debated


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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?


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00:18:40,000 --> 00:18:44,600
So, I asked the Professor of Geology
here at Cambridge University


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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,


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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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