Charles Darwin and the Tree of Life Page #6

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lizards and crocodiles.

And, of course, they included the group

that, back then,

came to dominate the land...

the dinosaurs.

But 65 million years ago,

a great disaster overtook the Earth.

Whatever its cause, a great proportion

of animals were exterminated.

All the dinosaurs disappeared,

except for one branch

whose scales had become

modified into feathers.

They were the birds.

While they spread through the skies,

a small, seemingly insignificant,

group of survivors began to increase

in numbers on the ground beneath.

These creatures differed

from their competitors

in that their bodies were warm

and insulated with coats of fur.

They were the first mammals.

With much of the land left vacant

after the great catastrophe,

they now had their chance.

Their warm, insulated bodies

enabled them to be active at all times,

at night as well as during the day.

And in all places,

from the Arctic to the tropics,

in water as well as on land,

on grassy plains and up in the trees.

There can be no doubt about

our close relationship

to these chimpanzees.

Our bodies are so similar.

The proportions of our limbs

or our faces may differ,

but otherwise we are

very, very similar.

The arrangement of our internal organs,

the chemistry of our blood,

the way our bodies work,

all these are almost identical.

And DNA confirms that.

Indeed, we are as closely related

to chimpanzees

and the rest of the apes and monkeys,

as say, lions are to tigers

and to the rest of the cat family.

Suddenly, an image from our remote past

comes vividly to light,

the time when our distant ancestors,

in order to keep up

with the changing environment,

had to wade and keep their heads

above water in order to find food.

That crucial moment

when our far distant ancestors

took the step away from being apes

and a step towards humanity.

The Natural History Museum is one of

the most important museums of its kind

in the world.

Richard Owen brought it into existence,

but, over a century later,

discoveries from

many branches of science

have shown that his belief

that species can never change

but always remain exactly the same

was mistaken.

It was Charles Darwin's profound

insights that have proved to be true.

And now, to mark

the 200th anniversary of his birth,

his statue is being taken

from its out-of-the-way location

to be placed centre stage

in the main hall.

Darwin's great insight revolutionised

the way in which we see the world.

We now understand

why there are so many different species.

Why they are distributed

in the way they are around the world.

And why their bodies and our bodies

are shaped in the way that they are.

Because we understand

that bacteria evolve,

we can devise methods of dealing

with the diseases they cause.

And because we can disentangle

the complex relationships

between animals and plants

in a natural community,

we can foresee some of the consequences

when we start to interfere

with those communities.

But above all, Darwin has shown us

that we are not apart

from the natural world.

We do not have dominion over it.

We are subject to its laws and processes

as are all other animals on Earth

to which indeed we are related.

(HE CHUCKLES)

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