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~ STRAUSS THE ELDER:
Opus 39 Tivoli-Rutsch Walzer
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In the 19th century,
the city of Vienna was the capital of an empire
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which held together a multitude of nations
and languages.
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It was a famous centre for music,
literature and the arts.
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Science was suspect in conservative Vienna,
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particularly biological science.
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But unexpectedly, Austria was also
the seedbed for one scientific idea,
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and in biology, that was revolutionary.
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This is the old university of Vienna.
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Here, the founder of genetics, and therefore
of all the modern life sciences, Gregor Mendel,
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got such little university education as he had.
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He came here at a historic time in the struggle
between tyranny and freedom of thought.
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In 1848, shortly before he came,
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two young men had published,
faraway in London, in German,
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a manifesto which begins with the phrase:
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"Ein Gespenst geht um Europa" -
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"A spectre is haunting Europe" -
the spectre of communism.
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Of course, Karl Marx and Friedrich Engels
in The Communist Manifesto
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didn 't create the revolutions in Europe.
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But they gave it the voice.
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And so, in this square...
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...students protested,
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the Austrian Empire, like others, shook,
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Metternich resigned, the Emperor abdicated.
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~ NIELSEN: Sixth Symphony
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Emperors go, but empires remain.
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The new Emperor of Austria
was a young man of 18, Franz Josef,
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who reigned like a medieval autocrat,
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until the ramshackle empire fell to pieces
during the First World War.
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The patriots' speeches fell silent.
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The reaction under the young Emperor
was total.
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At that moment, the ascent of man
was quietly set off in a new direction
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by the arrival at the University of Vienna
of Mendel.
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He'd been born Johann Mendel, a farmer's son.
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Gregor was the name he was given
when he became a monk.
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He was not a clever student.
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His examiner wrote: "He lacks insight and the
requisite clarity of knowledge" and failed him.
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The farm boy become monk had no choice,
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except to withdraw again into the anonymity
of the monastery at Brno,
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which is now part of Czechoslovakia.
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When Mendel came back from Vienna in 1853,
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he was, at the age of 31, a failure.
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He had been sent by this Augustinian order
of St Thomas here in Brno.
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And they were a teaching order.
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This is the library, not so much of a monastery
as of a teaching order.
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The Austrian Government wanted the bright
boys among the peasantry taught by monks.
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And Mendel had failed to qualify as a teacher.
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He had to make up his mind,
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whether to live the rest of his life
as a failed teacher or as... what?
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As the boy Hansl, the young man Johann,
he decided -
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not as the monk Gregor.
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He went back in thought,
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to what he had learnt on the farm
and had been fascinated by ever since -
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plants.
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At Vienna he had been under the influence
of the one great biologist he ever met,
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Franz Unger,
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who took a concrete,
practical view of inheritance -
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no spiritual essences, no vital forces...
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Real facts.
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And Mendel decided to devote his life
to practical experiments in biology,
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here in the monastery.
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A bold, silent, and I think, secret stroke,
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because the local bishop wouldn 't even
allow the monks to teach biology.
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Mendel began his formal experiments about two
or three years after he came back from Vienna,
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say about 1856.
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He says in his paper
that he worked for eight years.
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The plant that he'd chosen, very carefully,
is the garden pea.
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He picked out seven characters for comparison -
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shape of seed, colour of seed and so on,
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finishing with tall in stem versus short stemmed.
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And that last character
is the one that I've chosen to display.
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Tall...
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versus short.
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We do the experiment exactly as Mendel did.
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We start by making a hybrid of tall and short.
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In order to make sure
that the short plant does not fertilise itself,
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we emasculate it.
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And then we artificially inseminate it
from the tall plant.
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The process of fertilisation takes its course.
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The pollen tubes grow down to the ovules.
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The pollen nuclei,
the equivalent of sperm in an animal,
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go down the pollen tubes and reach the ovules
just as they do in any fertilised pea.
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The plant bears pods that don 't yet, of course,
reveal their character.
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The peas from the pods are now planted.
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As the time-lapse film shows,
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their development is at first indistinguishable
from that of any other garden peas.
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Mendel had guessed that a simple character
is regulated by two particles -
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we now call them genes.
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Each parent contributes one of the two particles.
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If the two particles or genes are different,
one will be dominant and the other recessive.
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The crossing of tall peas with short
is a first step in seeing if this is true.
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And lo and behold, here is the first generation -
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and they are all tall.
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In the language of modern genetics,
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the character tall is dominant
over the character short.
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It is not true that the hybrids
average the height of their parents,
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they are all tall plants.
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Now the second step.
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We form the second generation as Mendel did.
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We fertilise the hybrids,
this time with their own pollen.
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We allow the pods to form, plant the seeds...
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...and here's the second generation.
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In one mating out of every four,
two recessive genes have come together.
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And as a result, one plant out of four is short,
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and three are tall.
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This is the famous ratio of one out of four, or 1:3,
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that everyone associates with Mendel's name,
and rightly so.
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Mendel published his results in 1866...
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and achieved instant oblivion.
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No-one cared, no-one understood his work.
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Even when he wrote to a distinguished,
rather stuffy figure in the field, Karl Nageli,
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it was clear that he had no notion
what Mendel was talking about.
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Of course,
if Mendel had been a professional scientist,
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he would now have pushed the results -
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published the paper more widely...
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...in France or Britain.
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However, at this moment, in 1868,
two years after the paper was published
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a most unexpected thing happened to Mendel.
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He was elected abbot of this monastery.
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And for the rest of his life he carried out
his duties with commendable zeal...
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...and a touch of neurotic punctilio.
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He told Nageli that he hoped to go on
doing breeding experiments.
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But the only thing that he was able to breed
were bees.
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He had always been anxious
to push his work from plants to animals.
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And of course, being Mendel,
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he had his usual mixture of splendid
intellectual fortune and practical bad luck.
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He made a hybrid strain of bees
which gave excellent honey,
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but alas, was so ferocious that it stung
everybody for miles around
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and had to be destroyed.
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Mendel seems to have been more exercised
about tax demands on the monastery
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than about its religious leadership.
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And there is a hint that he was regarded
as unreliable by the Emperor's secret police.
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Under the Abbot's broad brow,
there lay a weight of private thought.
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The puzzle of Mendel's personality
is an intellectual one.
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No-one could have conceived
those experiments...
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...unless they had clearly in their minds
the answer that they were going to get.
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It's a strange state of affairs.
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And I should give you chapter and verse for that.
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First, a practical point.
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Mendel chose seven differences between peas
to test for at the same time,
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such as tall versus short and so on.
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Now, the pea does have
seven pairs of chromosomes,
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so you can test for seven differences,
lying on seven different chromosomes.
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But that's the largest number
you could have chosen.
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You couldn 't test for eight without getting
two lying on the same chromosome
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and therefore being at least partially linked.
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Nobody had heard of linkage then,
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nobody had even heard of chromosomes
at the time Mendel was working on the paper.
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Now, you can be destined to be
the abbot of a monastery,
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you can be chosen by God,
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but you can 't have that luck.
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Mendel must have done a good deal
of experiment before the formal work,
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in order to tease out these and convince himself
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that seven qualities
is just what he could get away with.
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And there we glimpse
the great iceberg of the mind,
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in that secret hidden face of Mendel's
on which the paper and the achievement float.
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And you see it.
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You see it on every page of the manuscript.
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The symbolism, the clarity of the exposition -
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everything is modern genetics,
done more than 100 years ago by an unknown.
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And done by an unknown
who had one crucial inspiration -
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that characters separated
in an all-or-none fashion.
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This in an age where every time
breeders observed this in a hybrid,
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it was thrown away because people were
convinced that hereditary must go by averaging.
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Where did Mendel get the model
of an all-or-nothing heredity?
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Now, I think I know.
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But, of course,
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I can 't look into his head either.
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But there does exist one model,
and it's existed since time immemorial,
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which is so obvious
that no scientist would think of it.
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But a child or a monk might.
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That model is sex.
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Animals have been copulating
for millions of years.
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And males and females of the same species
don 't produce monsters,
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they produce either a male or a female.
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Men and women have been going to bed
for upward of a million years at least.
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And they produce what?
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Men or women.
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Some such simple powerful model of
an all-or-nothing way of passing on differences
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must have been in Mendel's mind,
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so that the experiments and the thought
were clearly made for him of whole cloth
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and seen from the inception.
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The monks, I think, knew this.
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I think they didn 't like what he was doing.
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I think the bishop who demurred
at the pea-breeding experiments didn 't like it.
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Of course,
his rout-about revolutionary colleagues
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whom he often sheltered in the monastery,
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they were fond of him till the end.
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When he died in 1884 at the age of 62,
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the great Czech composer Janacek
played the organ at his funeral.
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But the monks elected a new abbot,
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and he burned all Mendel's papers.
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~ JANACEK: Glagolitic Mass
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Mendel's great experiment remained forgotten
for over 30 years,
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till it was resurrected in 1900.
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So his discoveries belong, in effect,
to this century,
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when the study of genetics
all at once blossoms from them.
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To begin at the beginning.
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Life on earth has been going on
for 3,000 million years or more.
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For two-thirds of that time, organisms
reproduced themselves by cell division.
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Division produces identical offspring.
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New forms appear only rarely, by mutation.
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For all that time, evolution was very slow.
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The first organisms to reproduce sexually
were, it now seems,
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a kind of blue-green algae.
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That was less than 1,000 million years ago.
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Sexual reproduction begins there,
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first in plants, then in animals.
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~ PINK FLO YD: Ummagumma
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Sex produces diversity.
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And diversity is the propeller of evolution.
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The acceleration in evolution
is responsible for the existence now
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of the dazzling variety of shape,
colour and behaviour in species,
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and also for individual differences
within species.
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All that was mde possible
by the emergence of two sexes.
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Two is the magic number.
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That is why sex and courtship
are so highly evolved in different species.
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It's why sex is geared so precisely
to the animal's environment.
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If the grunion could have adapted themselves
without natural selection,
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then sex would not be necessary.
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Sex is itself
a mode of natural selection of the fittest.
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Stags don 't fight to kill,
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only to establish their right to choose the female.
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The multiplicity of shape, colour and behaviour
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is produced by the coupling of genes,
as Mendel guessed.
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As a matter of mechanics,
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the genes are strung out
along the chromosomes,
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which become visible
only when the cell is divided.
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But the question is not
how the genes are arranged.
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The modern question is, how do they act?
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The genes are made of nucleic acid.
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That is where the action is.
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How the message of inheritance
is passed from one generation to the next,
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was discovered in 1953.
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And it's the adventure story of science
in the 20th century.
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I suppose the moment of drama
is the autumn of 1951,
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when a young man in his twenties,
James Watson, arrives in Cambridge
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and teams up with a man of 35, Francis Crick,
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to decipher the structure
of deoxyribonucleic acid -
240
00:24:48,920 --> 00:24:50,876
DNA for short.
241
00:24:52,040 --> 00:24:56,909
DNA is a nucleic acid, and it had become clear
in the preceding ten years
242
00:24:57,800 --> 00:25:03,955
that there the chemical message is
carried from generation to generation.
243
00:25:05,560 --> 00:25:08,199
Two questions then faced the searchers,
244
00:25:09,280 --> 00:25:13,831
in Cambridge and in laboratories
as far afield as California and further.
245
00:25:16,440 --> 00:25:19,591
What is the chemistry,
246
00:25:20,480 --> 00:25:23,392
and what is the architecture?
247
00:25:23,480 --> 00:25:25,436
What is the chemistry?
248
00:25:25,520 --> 00:25:31,868
Well, it was clear that DNA
is made of sugars and phosphates -
249
00:25:31,960 --> 00:25:34,599
that's sure to be there for structural reasons -
250
00:25:34,680 --> 00:25:39,549
and four specific small molecules, or bases.
251
00:25:41,880 --> 00:25:44,314
Two of them are very small molecules,
252
00:25:45,400 --> 00:25:48,437
thymine and cytosine.
253
00:25:53,880 --> 00:25:56,713
And two of them are rather larger...
254
00:25:58,040 --> 00:25:59,951
...guanine and adenine.
255
00:26:04,280 --> 00:26:09,752
It's usual in structural work to represent
the small bases simply by a hexagon
256
00:26:09,840 --> 00:26:13,355
and the large bases by the bigger figure.
257
00:26:15,320 --> 00:26:18,437
But a building is not a heap of stones,
258
00:26:18,520 --> 00:26:22,433
and a DNA molecule is not a heap of bases.
259
00:26:23,480 --> 00:26:28,918
What gives it its structure
and therefore its function?
260
00:26:30,080 --> 00:26:37,111
It was clear by then that the DNA molecule
is a long, extended chain,
261
00:26:37,200 --> 00:26:40,988
but rather rigid - a kind of organic crystal.
262
00:26:41,080 --> 00:26:45,949
And it seemed likely that it would be a helix.
263
00:26:47,720 --> 00:26:50,837
How many helixes...
264
00:26:50,920 --> 00:26:53,832
how many spirals in parallel?
265
00:26:53,920 --> 00:26:56,593
One, two, three, four?
266
00:26:56,680 --> 00:26:59,752
There was a division of opinion
into two main camps -
267
00:26:59,840 --> 00:27:03,515
the two-helix camp
and the three-helix camp.
268
00:27:03,600 --> 00:27:06,876
And then, at the end of 1952,
269
00:27:06,960 --> 00:27:12,318
the great genius of structural chemistry,
Linus Pauling, in California,
270
00:27:12,400 --> 00:27:15,915
proposed a three-helix model.
271
00:27:17,000 --> 00:27:21,630
The backbone of sugar and phosphate
ran down the middle
272
00:27:21,720 --> 00:27:24,029
and the bases stuck out in all directions.
273
00:27:25,080 --> 00:27:30,393
That arrived in Cambridge in... February 1953.
274
00:27:31,800 --> 00:27:34,109
There was something wrong with it
from the outset.
275
00:27:35,560 --> 00:27:38,199
It may have been mere relief.
276
00:27:38,280 --> 00:27:43,070
It may have been
a touch of malicious perversity,
277
00:27:43,160 --> 00:27:45,879
which made Jim Watson decide there and then
278
00:27:45,960 --> 00:27:49,396
that he would go for the double helix...
279
00:27:51,160 --> 00:27:55,597
...moreover with the backbones running
on the outside,
280
00:27:55,680 --> 00:27:58,638
a sort of spiral staircase
281
00:27:58,720 --> 00:28:03,077
with the sugar and phosphate
running like two handrails.
282
00:28:06,240 --> 00:28:08,356
Agonies of experimentation
283
00:28:08,440 --> 00:28:13,468
to see how the bases would fit
as the steps in that model.
284
00:28:15,640 --> 00:28:19,155
And then, all at once, it became self-evident.
285
00:28:19,240 --> 00:28:22,915
Of course there must be, on each step,
286
00:28:23,000 --> 00:28:27,391
a small base and a large base,
287
00:28:27,480 --> 00:28:29,198
but not any large base.
288
00:28:29,280 --> 00:28:32,078
Thymine must be matched by adenine.
289
00:28:32,960 --> 00:28:36,555
And if you have cytosine,
290
00:28:36,640 --> 00:28:40,076
then it must be matched by guanine.
291
00:28:40,160 --> 00:28:45,439
The bases go together in pairs
of which each determines the other.
292
00:28:46,240 --> 00:28:49,755
So the model of the DNA molecule
is a spiral staircase,
293
00:28:49,840 --> 00:28:52,195
a right-handed spiral,
294
00:28:52,280 --> 00:28:56,432
in which each tread is of the same size,
at the same distance from the next,
295
00:28:56,520 --> 00:29:01,799
[Skipped item nr. 295]
296
00:28:56,520 --> 00:29:01,799
And turns at the same rate -
36o - between treads.
297
00:29:01,880 --> 00:29:03,711
And...
298
00:29:03,800 --> 00:29:08,828
if cytosine is at one end of a tread,
then guanine is at the other,
299
00:29:08,920 --> 00:29:11,354
and so for the other base pair.
300
00:29:11,440 --> 00:29:13,715
Let's build the molecule.
301
00:29:19,800 --> 00:29:21,756
That's a base pair.
302
00:29:22,640 --> 00:29:27,555
The dotted lines between the two ends
are the hydrogen bonds.
303
00:29:27,640 --> 00:29:31,110
We'll put it into the position
at which we're going to stack it.
304
00:29:31,200 --> 00:29:33,350
And now we'll stack it...
305
00:29:34,760 --> 00:29:37,558
...at the left-hand side of the picture
306
00:29:37,640 --> 00:29:40,234
where we're going to build the whole molecule.
307
00:29:46,240 --> 00:29:47,878
Here is a second pair.
308
00:29:47,960 --> 00:29:51,589
It might be of the same kind as the first
or the opposite kind.
309
00:29:54,560 --> 00:29:56,869
We stack it over the first pair,
310
00:29:56,960 --> 00:29:59,190
and turn it through 36o.
311
00:30:00,560 --> 00:30:03,313
Here's a third pair
to which we do the same thing.
312
00:30:03,400 --> 00:30:05,356
And so on.
313
00:30:13,160 --> 00:30:18,154
These treads are a code
which will tell the cell, step by step,
314
00:30:18,240 --> 00:30:21,835
how to make one of the proteins
necessary to life.
315
00:30:21,920 --> 00:30:25,117
The gene is forming visibly in front of our eyes,
316
00:30:25,200 --> 00:30:30,752
and the handrails of sugar and phosphates
hold the spiral staircase rigid on each side.
317
00:30:38,240 --> 00:30:41,949
The spiral DNA molecule is a gene -
318
00:30:42,040 --> 00:30:44,190
a gene in action -
319
00:30:44,280 --> 00:30:47,317
and the treads are the steps by which it acts.
320
00:30:53,200 --> 00:30:56,476
On 2nd April, 1953,
321
00:30:56,560 --> 00:30:59,677
James Watson and Francis Crick
sent to Nature
322
00:30:59,760 --> 00:31:04,515
the paper which describes this structure in DNA,
323
00:31:04,600 --> 00:31:06,909
on which they had worked for only 18 months.
324
00:31:07,960 --> 00:31:13,830
The model patently lends itself
to the process of replication
325
00:31:13,920 --> 00:31:16,070
which is fundamental to life.
326
00:31:18,920 --> 00:31:21,912
When a cell divides, the two spirals separate,
327
00:31:22,000 --> 00:31:26,710
each base fixes opposite to it
the other member of the pair to which it belongs
328
00:31:26,800 --> 00:31:30,918
so that when a cell divides,
the same gene is reproduced.
329
00:31:36,440 --> 00:31:38,590
The magic number two here
330
00:31:38,680 --> 00:31:44,550
is the means by which a cell passes on
its genetic identity when it divides.
331
00:31:55,560 --> 00:31:59,235
Only the sperm and the egg are incomplete.
332
00:31:59,320 --> 00:32:01,072
They're half cells.
333
00:32:01,160 --> 00:32:03,594
They carry half the number of genes.
334
00:32:03,680 --> 00:32:06,752
Then, when the egg is fertilised by the sperm,
335
00:32:06,840 --> 00:32:10,355
the total of DNA instructions is assembled again.
336
00:32:10,440 --> 00:32:13,671
The fertilised egg is then a complete cell
337
00:32:13,760 --> 00:32:16,513
and it's the model for every cell in the body.
338
00:32:16,600 --> 00:32:20,036
Every cell is formed
by division of the fertilised egg,
339
00:32:20,120 --> 00:32:23,510
and so it's identical with it
in its genetic makeup.
340
00:32:24,320 --> 00:32:26,390
Like this chick embryo,
341
00:32:26,480 --> 00:32:30,632
it has the legacy of the fertilised egg
all through life.
342
00:32:42,840 --> 00:32:47,152
As the embryo develops, the cells differentiate.
343
00:32:47,240 --> 00:32:49,674
Along the primitive streak,
344
00:32:49,760 --> 00:32:52,991
the beginnings of the nervous system
are laid down.
345
00:33:08,280 --> 00:33:12,353
Clumps of cells on either side
will form the backbone.
346
00:33:12,440 --> 00:33:14,590
The cells specialise.
347
00:33:15,560 --> 00:33:17,516
Nerve cells.
348
00:33:21,440 --> 00:33:23,476
Muscle cells.
349
00:33:31,160 --> 00:33:34,516
Connective tissue - the ligaments and tendons.
350
00:33:35,560 --> 00:33:37,516
Blood cells.
351
00:34:04,280 --> 00:34:05,998
Blood vessels.
352
00:34:06,760 --> 00:34:11,675
The cells specialise
because they've accepted the DNA instruction
353
00:34:11,760 --> 00:34:16,914
to make the proteins that are appropriate
to the functioning of that cell and no other.
354
00:34:17,760 --> 00:34:20,718
This is the DNA in action.
355
00:36:16,480 --> 00:36:18,436
- It's a little girl.
- Oh!
356
00:36:18,520 --> 00:36:20,795
(All laugh)
MAN: That's another wedding!
357
00:36:20,880 --> 00:36:22,836
(Laughter)
358
00:36:24,800 --> 00:36:28,190
The baby is an individual from birth.
359
00:36:28,280 --> 00:36:33,957
The coupling of genes from both parents
stirred the pool of diversity.
360
00:36:34,040 --> 00:36:37,794
The child inherits gifts from both parents,
361
00:36:37,880 --> 00:36:40,599
and chance has now combined these gifts
362
00:36:40,680 --> 00:36:44,036
in a new and original arrangement.
363
00:36:45,320 --> 00:36:47,880
(Baby wails)
- There we are.
364
00:36:59,160 --> 00:37:02,038
The child is not a prisoner of its inheritance.
365
00:37:02,120 --> 00:37:05,192
It holds its inheritance as a new creation,
366
00:37:05,280 --> 00:37:09,193
which its future actions will unfold.
367
00:37:15,000 --> 00:37:16,956
(Cries)
368
00:37:18,120 --> 00:37:20,475
The child is an individual.
369
00:37:23,080 --> 00:37:25,036
The bee is not.
370
00:37:29,880 --> 00:37:33,668
The bee is one of a series of identical replicas.
371
00:37:38,120 --> 00:37:41,157
The queen is the only fertile female.
372
00:37:41,720 --> 00:37:48,193
When she mates with the drone, in mid-air,
she goes on hoarding his sperms.
373
00:37:48,280 --> 00:37:50,236
The drone dies.
374
00:37:51,280 --> 00:37:55,273
If the queen now releases a sperm
with an egg she lays,
375
00:37:55,360 --> 00:37:58,397
she makes a worker bee a female.
376
00:37:59,200 --> 00:38:03,318
No sperm, and a drone is made. A male.
377
00:38:03,400 --> 00:38:05,356
A sort of virgin birth.
378
00:38:09,280 --> 00:38:12,272
It's a totalitarian paradise.
379
00:38:12,360 --> 00:38:15,272
Forever loyal, forever fixed,
380
00:38:15,360 --> 00:38:21,276
because it has shut itself off
from the adventure of diversity
381
00:38:21,360 --> 00:38:25,319
that drives and changes
the higher animals and man.
382
00:38:28,600 --> 00:38:32,912
A world as rigid as the bees
could be created among higher animals,
383
00:38:33,000 --> 00:38:36,390
even among men, by cloning.
384
00:38:36,480 --> 00:38:42,555
That is, by growing a colony or clone
of identical animals
385
00:38:42,640 --> 00:38:45,154
from cells of a single parent.
386
00:38:46,720 --> 00:38:50,269
Here is a mixed population of an amphibian -
the axolotl.
387
00:38:51,040 --> 00:38:55,431
Suppose we decide to fix on one type -
the speckled axolotl.
388
00:38:56,120 --> 00:38:58,475
We take some eggs from a speckled female
389
00:38:58,560 --> 00:39:01,438
and grow an embryo
which is destined to be speckled.
390
00:39:01,520 --> 00:39:05,479
Now we tease out from the embryo
a number of cells.
391
00:39:05,960 --> 00:39:07,916
They are identical cells.
392
00:39:08,000 --> 00:39:11,675
We are going to grow identical animals,
one from each cell.
393
00:39:12,760 --> 00:39:15,115
We need a carrier in which to grow the cells.
394
00:39:15,200 --> 00:39:17,236
Any carrier will do. She can be white.
395
00:39:17,720 --> 00:39:20,473
We take unfertilised eggs from the carrier
396
00:39:21,160 --> 00:39:23,993
and destroy the nucleus in each egg.
397
00:39:25,640 --> 00:39:27,596
This is a carrier egg
398
00:39:27,680 --> 00:39:33,869
and into it we insert one of the single identical
cells of the speckled parent of the clone.
399
00:39:37,720 --> 00:39:41,998
The clone of identical eggs made in this way
are all grown at the same time.
400
00:39:42,760 --> 00:39:45,228
Each egg divides at the same moment.
401
00:39:45,320 --> 00:39:47,470
Divides once, divides twice,
402
00:39:47,560 --> 00:39:49,516
and goes on dividing.
403
00:39:49,600 --> 00:39:52,637
All that is normal, exactly as in any egg.
404
00:40:04,600 --> 00:40:08,149
At this stage, the single cell divisions
are no longer visible.
405
00:40:08,240 --> 00:40:10,674
Each egg is turned into a kind of tennis ball,
406
00:40:10,760 --> 00:40:12,990
and begins to turn itself inside out.
407
00:40:13,960 --> 00:40:15,916
Still all the eggs are in step.
408
00:40:26,120 --> 00:40:30,159
Each egg folds over to form the animal,
always in step.
409
00:40:30,240 --> 00:40:34,836
A regimented world in which the units
obey every command identically
410
00:40:34,920 --> 00:40:36,876
at the identical moment.
411
00:40:36,960 --> 00:40:40,794
Except one unfortunate, that's been deprived
and is falling behind.
412
00:40:45,720 --> 00:40:47,790
And finally the clone of individuals.
413
00:40:47,880 --> 00:40:50,314
Each of them an identical copy of the parent.
414
00:40:50,400 --> 00:40:54,279
Each of them a virgin birth like the worker bee.
415
00:41:02,080 --> 00:41:04,674
Should we make clones of human beings?
416
00:41:04,760 --> 00:41:08,912
Copies of a beautiful mother, perhaps,
or of a clever father?
417
00:41:09,000 --> 00:41:10,956
Of course not.
418
00:41:12,080 --> 00:41:14,548
Cloning is the stabilisation of one form,
419
00:41:14,640 --> 00:41:18,679
and that runs against
the whole current of creation.
420
00:41:18,760 --> 00:41:20,716
Of human creation, above all.
421
00:41:26,720 --> 00:41:30,838
Yet it's odd that the myths of creation
in human cultures
422
00:41:30,920 --> 00:41:35,357
seem almost to yearn back
for an ancestral clone.
423
00:41:36,040 --> 00:41:41,478
There is a strange suppression of sex
in the ancient stories of origins.
424
00:41:42,640 --> 00:41:45,871
Eve is cloned from Adam's rib,
425
00:41:45,960 --> 00:41:49,111
and there's a preference for virgin birth.
426
00:41:49,720 --> 00:41:52,951
Happily, we're not frozen in identical copies.
427
00:41:53,040 --> 00:41:56,715
In the human species, sex is highly developed.
428
00:41:56,800 --> 00:41:59,792
The female is receptive at all times.
429
00:41:59,880 --> 00:42:02,235
She has permanent breasts.
430
00:42:02,640 --> 00:42:05,518
She takes an active part in sexual selection.
431
00:42:06,640 --> 00:42:10,155
Eve's apple, as it were, fertilises mankind.
432
00:42:10,240 --> 00:42:15,075
Or at least spurs it
to its ageless preoccupation.
433
00:42:17,040 --> 00:42:18,996
~ Harp With Variations
434
00:43:26,280 --> 00:43:31,308
It's obvious that sex has a special character
for human beings.
435
00:43:31,400 --> 00:43:33,550
It has a special biological character.
436
00:43:33,640 --> 00:43:37,997
Let's take one simple, down -to-earth criterion
for that.
437
00:43:38,080 --> 00:43:43,950
We are the only species
in which the female has orgasms.
438
00:43:45,000 --> 00:43:46,956
That's remarkable, but it is so.
439
00:43:47,880 --> 00:43:55,560
It is a mark in general of the fact that there is
much less difference between men and women
440
00:43:56,520 --> 00:43:59,193
in the biology of sex and in sexual behaviour,
441
00:43:59,280 --> 00:44:01,236
than there is in other species.
442
00:44:02,000 --> 00:44:04,594
That may seem a strange thing to say,
443
00:44:04,680 --> 00:44:06,750
but to the gorilla and the chimpanzee,
444
00:44:06,840 --> 00:44:09,991
where there are enormous differences
between male and female,
445
00:44:10,080 --> 00:44:12,036
it would be obvious.
446
00:44:13,520 --> 00:44:16,080
So much for biology.
447
00:44:17,000 --> 00:44:21,039
But there is a point on the borderline
between biology and culture
448
00:44:21,120 --> 00:44:26,956
which really marks the symmetry
in sexual behaviour I think very strikingly.
449
00:44:27,040 --> 00:44:28,996
It's an obvious one.
450
00:44:29,080 --> 00:44:33,073
We are the only species
that copulate face to face.
451
00:44:35,160 --> 00:44:37,879
And that's universal in all cultures.
452
00:44:38,760 --> 00:44:45,871
It's an expression of, to my mind,
a general equality
453
00:44:45,960 --> 00:44:48,997
which has been important
in the evolution of man,
454
00:44:49,080 --> 00:44:52,834
I think right back
to the time of Australopithecus.
455
00:44:52,920 --> 00:44:56,754
Why? Well, we have something to explain.
456
00:44:56,840 --> 00:45:00,549
We have to explain
the speed of human evolution
457
00:45:00,640 --> 00:45:05,668
over a matter of one, three,
let's say five million years at most.
458
00:45:05,760 --> 00:45:07,716
Terribly fast.
459
00:45:07,800 --> 00:45:12,828
Natural selection simply doesn 't act
as fast as that on animal species.
460
00:45:12,920 --> 00:45:17,232
We must have supplied a form of selection
of our own,
461
00:45:17,920 --> 00:45:21,196
and the obvious choice is sexual selection.
462
00:45:21,280 --> 00:45:27,958
There is evidence now that women marry men
who are intellectually like them.
463
00:45:28,720 --> 00:45:31,553
Men marry women
who are intellectually like them.
464
00:45:31,640 --> 00:45:34,598
If that really goes back
over some millions of years,
465
00:45:34,680 --> 00:45:38,514
then it means that selection for skills
has always been important
466
00:45:38,600 --> 00:45:40,750
on the part of both sexes.
467
00:45:43,120 --> 00:45:47,875
Yet, if that had been the only selective factor,
468
00:45:47,960 --> 00:45:50,838
then we would be much more homogeneous
than we are.
469
00:45:50,920 --> 00:45:54,754
What keeps alive the variety in human beings?
470
00:45:56,720 --> 00:45:58,870
That's a cultural point.
471
00:45:59,760 --> 00:46:08,111
In every culture, there are special safeguards
to make for variety.
472
00:46:09,200 --> 00:46:12,590
The most striking of them is
the prohibition of incest.
473
00:46:12,680 --> 00:46:14,636
Well, for the man in the street.
474
00:46:14,720 --> 00:46:16,950
Doesn 't always apply to royal families.
475
00:46:17,040 --> 00:46:21,033
The prohibition of incest only has a meaning
476
00:46:21,120 --> 00:46:26,353
if it is designed to prevent older males
dominating a group of females,
477
00:46:26,440 --> 00:46:29,830
as they do in, let us say, ape groups.
478
00:46:33,200 --> 00:46:36,954
Most of the world's literature,
most of the world's art,
479
00:46:37,040 --> 00:46:40,430
is preoccupied with boy meets girl.
480
00:46:40,520 --> 00:46:45,196
We tend to think of that
as being a sexual preoccupation.
481
00:46:45,280 --> 00:46:47,236
But, of course, that's a mistake.
482
00:46:48,560 --> 00:46:55,033
It expresses the fact that
we are uncommonly careful in the choice,
483
00:46:55,120 --> 00:46:57,076
not of whom we take to bed,
484
00:46:57,160 --> 00:47:01,073
but by whom we are to beget children.
485
00:47:03,440 --> 00:47:08,560
Sex was invented as a biological instrument
by the blue-green algae.
486
00:47:08,640 --> 00:47:16,194
But as an instrument in the ascent of man,
which is basic to cultural evolution,
487
00:47:16,280 --> 00:47:19,158
it was invented by man himself.
488
00:47:21,720 --> 00:47:23,676
~ SCHUMANN: Reveries
489
00:47:23,760 --> 00:47:26,718
Spiritual and carnal love are inseparable.
490
00:47:26,800 --> 00:47:29,917
A poem by John Donne says that.
491
00:47:33,160 --> 00:47:36,152
"All day the same our postures were
492
00:47:36,240 --> 00:47:39,630
And we said nothing all the day.
493
00:47:40,840 --> 00:47:44,833
But O alas, so long, so far
494
00:47:44,920 --> 00:47:47,639
Our bodies, why do we forbear?
495
00:47:49,280 --> 00:47:54,593
This ecstasy doth unperplex
and tell us what we love
496
00:47:55,600 --> 00:47:58,831
Love's mysteries in souls do grow
497
00:47:58,920 --> 00:48:01,957
But yet the body is his book."