字幕表 動画を再生する 英語字幕をプリント In the late summer of 1859, Charles Darwin finally completed the last paragraph of his greatest work on The Origin Of Species. But he wasn't drawing his inspiration from the exotic islands that he'd visited on his famous voyage on HMS Beagle. A chalk bank in Kent, near his house at Downe, provided his metaphor for the laws that explain the diversity of life on our planet. It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us. Darwin was unleashing a new vision of nature, where species evolved independently from the guiding hand of a creator. The established vision of a harmonious world, divinely ordaine to serve God's noblest creation, mankind, would be shattered. He was very aware that what he was dealing with was effectively intellectual dynamite, and he kept most of his thoughts about what he was doing in terms of where man might come from, where new species might arise, effectively secret. It was a secret with which Darwin had wrestled for 20 years. 20 years of unflinching support from his wife Emma, who feared that her beloved husband might be consigned to eternal damnation for challenging traditional beliefs. Together they would endure two decades of debilitating illness, self-doubt, and family tragedy. It was a life struggle that Darwin also saw among the animals and plants in the fields and tangled banks of the Kentish countryside. A struggle that is a founding principle of his theory of natural selection. And the last paragraph of the Origin Of Species really goes out with a perfect bang. The whole book has been about the struggle for existence and what Tennyson had called nature red in tooth and claw. The last paragraph gives, to me, a sense of hope. It sort of shows that this war of all against all, actually has a result and the result is the living world we see around us. The beauties of the tangled bank, the worms and the butterflies and the grass and the orchids, all of these beauties of nature emerge from Darwin's simple idea. There is grandeur in this view of life, with its several powers having been originally breathed into a few forms or into one, and that whilst this planet has gone cycling along according to the fixed laws of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved. Just as beauty and wonder emerge out of a war of nature, so too did Charles Darwin's great book evolve out of years of painstaking research and inner conflict. At the age of 33, Charles Robert Darwin was already an established gentleman naturalist. His substantial private income enabled him to pursue his particular interest, solving what had been called "the mystery of mysteries". How animals and plants might transmute or evolve. It was to find a quiet place to write that in 1842 he and his burgeoning family had moved to a house just outside London near the village of Downe, in Kent. After several fruitless searches in Surrey and elsewhere, we found this house and purchased it. I was pleased by the diversified appearance of the vegetation proper to a chalk district, and so unlike what I had been accustomed to in the Midland counties. And still more pleased with the extreme quietness and rusticity of the place. Darwin knew in the country there was space to expand his experiments, to walk, to observe nature. There was plenty of information there for him to draw on and then there was a very important factor for Darwin of getting into a space where he felt safe, with his secret theory of transmutation. In the early 1840s, transmutation or evolution was still a radical idea, associated with social revolution. It was a secret that he shared with his wife and first cousin Emma Wedgwood, whom he had married three years earlier. I marvel at my good fortune that Emma, so infinitely my superior in every single moral quality, should have consented to be my wife. Emma was the precondition for everything that he did. She... created a love-shaped space where he felt safe to work obsessively without fearing the loss of love and damaging their relationship. She was to nurse him through years of recurrent bouts of illness, the nature of which remains unclear to this day. Possibly damage caused by a South American parasite, inflamed by anxiety and nervous tension. 25 years' extreme spasmodic daily and nightly flatulence. Vomiting preceded by shivering, hysterical crying, dying sensations or half-faint and copious and very pallid urine. Air fatigues bring on head symptoms, nervousness when Emma leaves me. I think she was always concerned about his health. She was constantly trying to persuade him to have a day off here, go on a trip there, not because she wanted his company, but because she felt if he carried on working at the pace at which he was going, then he would become more ill. Emma was to provide Charles with ten children, seven of whom survived to adulthood. As a father, Charles Darwin did not conform to the standard Victorian stereotype of the distant and stern pater familias. Darwin was very much a family man. He writes rather wryly one year that his wife hadn't been doing very well last year because she hadn't had a baby, which is pretty rude for a Victorian, I have to say. But what's fascinating is that he used his children as experimental animals. He noted their expressions when they were crying, when they were angry and he saw how similar they were to the expression of a dog. He saw his family as part of the human family, the human family as part of the mammal family, the mammal family as at one with the primroses. And that really shows that he saw humankind as an intrinsic part of the living world and not apart from it. This was radically different from the established Christian view of the time, where mankind was God's special and separate creation. He kept his real opinions in a private notebook. Man in his arrogance thinks of himself as a great work, worthy of the interposition of a deity. More humble and I believe true, to think him created from animals. And Charles and Emma did what animals do, only they had a bed to do it in, upstairs. But then because Darwin believed strongly in analogy, it's not only animals that do what people do, but it's also plants that do what people do in strange and complicated ways. So from the marriage bed to the flower bed was only 100 yards and Darwin would go downstairs, out the back door, down to his flower beds where experiments were being performed and how these creatures, he even regarded some plants as simple animals, also reproduced themselves. Just over a year after he arrived at Downe, he felt bold enough to tentatively raise the issue of species change with his botanist friend Joseph Hooker. At last gleams of light have come and I'm almost convinced that species are not immutable. It is like confessing a murder. Hooker's response was noncommittal. Darwin retreated into his shell. If Hooker wouldn't buy it, then his old teachers at Cambridge certainly wouldn't. Even the most progressive members of the Anglican clergy still saw nature's beauty and abundance as divinely ordained for the benefit of the Lord's highest creation, man. The fundamental idea around nature for many people during the early part of the 19th century, particularly in Cambridge, but throughout Anglican Britain, was that of design. The world was made for man and probably the best way of explaining this is just to think about the 24 hour day. We think of that of course as just an outcome of astronomical chance, in the way that the planets work and so forth. For people who were sitting in Cambridge, the idea was basically the 24 hour day is... that's because humans need to sleep for eight hours. And everything around them is organised from that fact, from human need going outwards. To suggest that mankind was merely a product of nature risked attack from the black robed priests, the black beasts, as Darwin called them. But what he possibly feared even more was the loss of respect from the Cambridge dons who had taught and inspired him. Men such as the straight spoken Yorkshireman the Reverend Adam Sedgwick, professor of geology, who saw God's design in nature. "Denying this... " ".. Might brutalise it and sink the human race "into a lower grade of degradation than any into which it has fallen "since records tell us of its history. " Sedgwick represents a union, an uneasy union of science and religion that had prevailed since the 17th century, in Britain particularly. A division of labour in which those who study nature offer to those who study God, evidence of God's greatness and goodness and wisdom in the world about us and those who study God's revelation in the Bible offer reasons for believing in God that he has revealed to us and how to go to heaven. Nature doesn't tell us how to go to heaven, but it tells us that there is a God in heaven, who has revealed himself and how to get there in the Bible. It was with these traditional views in mind that in early 1844, Darwin began to prepare a manuscript that he hoped would eventually show even men like Sedgwick that evolution was a reality, and that he had found the mechanism that made it happen. But as a punctilious and cautious man, he needed to marshal his evidence. What he does there at Downe is really create a living laboratory. You know, a laboratory to go along with his career, as it were. It's not just Darwin sitting alone, looking out the window. Darwin didn't just use his house and gardens to observe and learn from nature. He bred pigeons and orchids, raised 50 varieties of gooseberry, and to counter the creationists, he became a beekeeper in order to show that the near perfect hexagons in honeycombs were made by instinct rather than divine design. My habits are methodical, my love of natural science has been steady and ardent. I have the strongest desire to understand or explain whatever I have observed. To group all facts under some general laws. He would also create a place to think. A rough oval shaped path of gravel was laid down and trees planted to provide him with a half kilometre walking circuit. He called it the Sand Walk. Darwin called the Sand Walk his thinking path. He watched the trees grow and many of them are still there... .. in the knowledge and hope that he would be able to pace around this plot and escape the pressure of sitting in one place and writing and squeezing one's ideas out the point of a pen. Darwin would lose himself in thought on the Sand Walk, so much so that the only way he could keep track of the time he spent there was to keep track of the laps and he kept track of the laps by a pile of flints, one of which he would kick to the side after a lap and when the whole pile had been moved across the path, he knew he had completed his exercise, that was your thinking time for the day. We, the subsequent generation, love the Sand Walk because we can imagine Darwin on it and think about what he can see from the sand... in the Sand Walk. He can see these climbing plants, the bryony in the hedge for example. He can see Great Puckland's field where he will, you know, formulate a concept of biodiversity. Secluded in his rural laboratory, Darwin's manuscript on what he was already calling natural selection developed into an essay, suitable for publication. Some of his text drew on the experiences he had on his round the world Beagle expedition. Out of the five years he spent on the voyage, he'd stayed just five weeks on the Galapagos Islands, collecting specimens of plants and different species of mockingbirds and finches. The significance of his Galapagos experience in the development of his theory has been overstated. Just as I think it's very common to imagine that great theories appear in a rush, through inspiration, all at once, as though every scientist is like Archimedes streaking along a street from his bath somewhere in Syracuse. So, we want the place where the inspiration hits to be glamorous and exotic and the Galapagos does that perfectly, but that's completely to get the origin of the origin entirely wrong. It was only back in London after his Galapagos visit that Darwin realised that the species of birds and plants he collected were subtly different from island to island, yet were closely similar to species on the South American continent. In the 1844 manuscript, he used this as evidence that new species had evolved as continental birds and plants adapted to the different island habitats.