Prática de Shadowing: How Fire Made Us Human - Aprenda a falar inglês com vídeo
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There is a cave in South Africa called Vondervörg.
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The name means miracle in Afrikaans.
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This cave contains up to 7 metres of sediment,
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deposits, layers that have built up millimetre by millimetre over hundreds of thousands of years,
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like a huge tower of human and even pre-human history.
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About one metre down, in a layer dating to roughly one million years ago,
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researchers from Boston University found charred plant material and burned bone fragments.
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Both had been heated to temperatures of around 500 degrees Celsius,
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almost 1000 degrees Fahrenheit.
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This was not a wildfire that swept through.
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The burning had happened inside the cave, repeatedly, over time, in the same spot.
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It was the oldest known fireplace in the world.
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The creatures who most probably made this fire were called Homo erectus.
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That name, as the Latin scholars among you will know, simply means upright human.
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They were not homo sapiens, not quite us.
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Their brains were smaller, their bones heavier, their foreheads thick and heavy.
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But they walked on two legs, they made stone tools, and importantly for what we're talking about today.
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They used fire.
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Now, nobody knows exactly when the first of our ancestors started using fire.
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One million years ago is simply as far back as the reliable evidence goes.
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What we do know is that for a very long period, our ancestors were not making fire, they were finding it.
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Fire breaks out in the wild, as it always has and always will.
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Lightning strikes a dry tree.
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A lava flow ignites grassland.
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Dry grass catches in the heat of a long summer.
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And almost every animal on earth, when this happens, does the same thing.
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It runs.
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Fire is scary.
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It's hot.
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Instinct kicks in and even the fiercest predator will run in the opposite direction.
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Homo erectus did something different.
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At some point, they approached.
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Perhaps they picked up a burning branch and carried it back.
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Perhaps they found smouldering wood and kept it alive.
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However it happened, the crucial step was this.
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They stopped merely fleeing fire and started managing it.
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Of course, this wasn't a simple task.
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As any seasoned camper will know, tending a fire and keeping it alight requires real effort.
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You have to find wood to burn, carry it, arrange it properly, and protect the flame from wind and rain.
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So keeping a fire alive required attention, planning and cooperation.
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It required something that looks, in other words, very much like care.
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And as for why Homo erectus would want to have a fire, well, there are numerous immediate benefits.
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Warmth through cold nights, light to see by, and perhaps most importantly, safety.
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A fire keeps large predators away.
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And in a world where leopards, lions, hyenas and sabre-toothed cats were a constant menace,
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especially in the darkness of night, fire was a wonderful deterrent.
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But fire changed humans in ways that go far deeper than warmth and safety.
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In 2009, a Harvard professor named Richard Wrangham published a book called Catching Fire,
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How Cooking Made Us Human.
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The argument, as you might guess from the title,
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is that cooking food rather than eating it raw is one of the fundamental differences between humans and every other animal.
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And the consequences go far deeper than simply getting to enjoy a hotter and, dare I say, tastier meal.
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His argument is this.
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Raw food is hard to digest.
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Your body has to work extremely hard to extract calories from uncooked meats, roots and plant material.
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Cooking changes all of that.
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It breaks down the cellular structure of food before it even enters your mouth.
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Proteins unravel.
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Starches become easier to absorb.
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Tough fibers soften.
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And cooked food releases anywhere between 30 and 100% more calories than the same food eaten raw.
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So if you are getting more energy from the same amount of food, you do not need such a large,
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energy-hungry digestive system to process it.
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And the energy you are no longer spending on digestion becomes available for something else.
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Wrangham's argument is that this surplus energy went to the brain.
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He points to Homo erectus, who appeared roughly 1.8 million years ago.
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Earlier homonyms, like Australopithecus, had large guts,
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small brains, and big teeth suited to chewing tough, raw food.
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Homo erectus had dramatically smaller teeth and a smaller gut, but a noticeably larger brain.
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This shift happens at roughly the time we see the first signs of fire use.
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Wrangham's claim is that this is not a coincidence.
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cooking made this transition possible perhaps cooking drove it now not everyone agrees some researchers argue
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that energy came from raw meat and bone marrow their argument is
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that eating more animal protein not cooking explains the anatomical changes
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but here is what is not in dispute we are the only animal on Earth that cooks its food.
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Chimpanzees are our closest living relatives.
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They share roughly 98% of our DNA, and they have never in any documented setting cooked anything.
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And it's not because they don't want to.
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In a series of experiments by researchers at Harvard and Yale,
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chimpanzees were given a choice between a raw piece of food and a cooked one.
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All 29 chimpanzees in the study chose the cooked option.
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And more strikingly, when the chimps were shown
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that they could place a raw piece of food into a device that would produce a cooked version afterwards, they were willing to wait.
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So even though they wanted to eat, they held back from eating the raw food,
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specifically in order to get the cooked version.
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So chimpanzees understand the transformation from raw to cooked food.
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They prefer the result.
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They will even delay gratification to get it.
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They just don't know how to use or make fire.
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Humans do, and that single difference may be the most consequential in the entire history of life on Earth.
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Now, there is one more physical consequence of fire we need to talk about.
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It concerns sleep.
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Before fire, our ancestors almost certainly slept in trees, as most great apes still do.
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Trees are safer from predators, but you don't have to have slept in many trees yourself to know
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that trees are not particularly comfortable places to spend the night.
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You wake up frequently, you sleep lightly and uncomfortably.
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Chimpanzees sleep around 10 hours a night because their sleep is so frequently disturbed.
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Humans sleep 7 to 8 hours and we sleep deeply.
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And to bring this back to fire, with a fire burning through the night, you could sleep on the ground and be safe.
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And because you felt safe, and you were safe, you could sleep properly.
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The deep, dreaming sleep that consolidates memory, repairs the body, and allows the brain to do its work.
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The depth of human sleep, tied to memory, learning, creativity, and health, may itself be,
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in part, a consequence of learning to manage fire.
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And by moving our beds from the branches to the ground, we created a new physical space, the circle.
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And it was in this circle, protected by the flames, that the second great transformation happened.
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We started to talk in a different way.
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An anthropologist at the University of Utah named Polly Weissner spent
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four decades studying a group of Kalahari desert bushmen in southern Africa.
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This group is one of the oldest surviving hunter-gatherer cultures on Earth.
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She analysed hundreds of their conversations and she found a very clear pattern.
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During the day, conversations were mostly practical,
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economic decisions, disputes, complaints, discussions about food and hunting.
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Around the fire at night, the topics were very different.
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Storytelling accounted for 81% of all conversations, compared to only 6% during the day.
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night, by firelight, people told stories about distant lands, about people they had never met,
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about ancestors and spirits and the distant past.
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They speculated about things they could not see, they laughed, they imagined.
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Many researchers argue this is where human language,
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storytelling and imagination really grew around the calm of the fire.
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Stories bind communities, they carry knowledge across generations,
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they let us think about distant places and people, past events and futures that have not yet happened.
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And the fire restructured domestic life in practical ways too.
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Cooking with fire requires different tasks, collecting the wood, starting the fire, tending the fire, doing the cooking,
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and of course someone still needs to go and hunt the unfortunate animal everyone is going to eat.
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This requires cooperation, specialisation, and division of labour.
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Often, though not always, cooking became associated more with women, and hunting more with men.
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And Wrangham, in the book I mentioned earlier, makes another more provocative suggestion.
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He argues that cooking may have been one of the early drivers of pair bonding,
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of a more stable relationship between a man and a woman, based less on romantic love than on mutual advantage.
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Imagine a woman crouching over a fire with cooked food in front of her.
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That food was valuable.
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It had taken time to prepare.
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And because it was soft, warm, and ready to eat, it could also be stolen.
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Wrangham's argument is that a man could provide protection,
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especially from other members of the group in exchange for a share of that cooked food.
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Over time, he suggests, this practical arrangement may have helped shape something closer to human pair bonding.
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Not marriage as we understand it today, but an early form of domestic partnership.
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It is, I should stress, simply a theory but an interesting one nonetheless
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that the first human couples got together
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and stayed together in order to protect their dinner
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so for hundreds of thousands of years then early humans found fire kept it
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and built their lives around it but importantly they were entirely at the mercy of finding it.
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If the flame went out, that was it.
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You had to wait for lightning to strike again or travel far to find fire somewhere else.
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The warmth, the safety, the cooked food, the community, all of it depended on a flame that someone,
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somewhere, had to have been lucky enough to find.
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That dependence is what changed around 400,000 years ago.
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We stopped waiting for the lightning and learned how to make fire ourselves.
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First, it's thought it was through percussion,
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striking pieces of flint against iron pyrite to create sparks that could catch in a small bundle of timber,
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small dry pieces of wood or leaves.
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Later came the friction method, spinning a dry wooden rod against a flat piece of softer
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wood until there's enough heat built up to set dry leaves or wood alight.
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There is of course no way to know what it felt like when the first person, wherever he or she was,
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figured out how to create fire.
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But it must have felt like magic, like you had just figured out the secret to one of the world's greatest puzzles.
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And they had, really.
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But for most of the million-year story of fire, the fuel was simple.
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It was wood for the most part.
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Sometimes dried grass, peat, charcoal or animal dung.
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Things that had grown under the sun, stored its energy and released it again as heat and light when they burned.
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And it was enough.
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Enough to build every civilization before roughly 300 years ago.
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The ancient Egyptians, classical Greece, the Roman Empire, medieval Europe, all of it ran on burning wood and charcoal.
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You could smelt metals, fire pottery, heat homes, cook food and light streets.
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Then, gradually, the wood started to run out.
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In Britain, by the 17th century, forests had been stripped.
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Wood for building ships, for building houses, for heating.
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All of it was scarce and getting increasingly expensive.
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But people still needed fire, or rather the heat that fire gave out.
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The answer was right under their noses, or to be precise, under their feet.
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Coal and later oil.
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Now, the existence of coal had been common knowledge for centuries.
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It washed up on the beach
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and you could collect it in small quantities from hillsides or from relatively close to the surface.
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And people in northeast England and south Wales had been burning it in small quantities for generations.
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But it was regarded as a poor substitute.
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Dirtier, smellier, and compared to wood, which you just got from trees,
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it was much harder to get at in any sort of useful quantity.
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But there wasn't an alternative.
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England was running out of trees.
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It was running out of wood.
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And this need, this desperation, was the first domino in the Industrial Revolution.
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And you could even argue every technological development that you and I benefit from today.
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In 1709, a man named Abraham Darby worked out how to make iron using coke,
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a purified, high-carbon form of coal.
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This was the first time someone had managed to make iron with coal rather than with charcoal, burnt wood.
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And this had considerable advantages.
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Using coal was much cheaper.
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It turned iron, and later steel, from scarce, expensive materials into industrial commodities.
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And more importantly, coal appeared to be virtually limitless.
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Before this, iron production was limited by the rate at which forests could grow back.
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After Derby, it was limited only by how fast you could dig.
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And Britain dug very fast.
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In 1700, roughly five-sixths of all coal mined in the entire world came from Britain.
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Annual iron output, which stood at around two
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and a half thousand tons in the early 1700s reached 2.5 million tons by 1850,
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a thousand-fold increase in just a century and a half.
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Now, I don't want to turn this into an episode about the Industrial Revolution, we already have one on that,
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it's episode number 150, But the main point is that this was primarily a fire revolution.
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It was about inventing better and better ways to create energy,
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to create heat, and then transform that into different forms of energy and industrial output.
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And after that came oil, which is an even more energy-dense fuel than coal, and being liquid is far easier to transport.
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What followed was the fastest transformation of human life in the entire million-year story of fire.
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Cars, aeroplanes, ships, factories, central heating, electric light, all of it at its root,
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a consequence of setting fire to stuff and using its heat.
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Now, it would be remiss of me not to mention the environmental side effects of all of this.
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The trillions of tons of CO2 this is all estimated to have released into the atmosphere, and what this might mean for the planet's future.
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But to come back to where we started, sometime around a million years ago,
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our early ancestors found fire in the wild and kept it burning.
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Then we learned how to make it ourselves.
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We used it to cook our food, shape our societies, and build things our ancestors could never have imagined.
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Fire might seem like just another part of the natural world, but for us humans, it changed everything.
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Okay then, that is it for today's episode on the history of fire.
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I hope it's been an interesting one and that you've learned something new.
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As always, I would love to know what you thought of this episode.
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Let me know in the comments below if you're listening somewhere where you can comment.
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And for the members among you, you can head right into our community forum at community.leonardoenglish.com and get chatting away to other curious minds.
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You've been listening to English Learning for Curious Minds by Leonardo English.
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I'm Alistair Budge.
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You stay safe and I'll catch you in the next episode.
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Thank you.
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Objetivos de fala para este trecho
Este vídeo é ideal para praticar a prática de conversação em inglês com foco em narrativas históricas e explanações detalhadas. O objetivo é melhorar a fluência ao articular conceitos complexos, como a evolução humana, e dominar a estrutura de frases longas com cláusulas explicativas. Além disso, ele ajuda a desenvolver a capacidade de transmitir informações de forma clara e envolvente, um marco crucial para a comunicação eficaz em inglês.
Banco de frases reutilizáveis
- "depósitos que se acumularam milímetro a milímetro ao longo de centenas de milhares de anos"
- "a evidência confiável chega até aqui"
- "gerenciar o fogo em vez de fugir dele"
- "requer atenção, planejamento e cooperação"
- "mudou os humanos de maneiras que vão muito além de calor e segurança"
Essas frases são perfeitas para shadow speech, pois combinam vocabulário específico com estruturas gramaticais comuns em contextos informativos. Ao repetí-las, você aprende a conectar ideias e a manter um ritmo natural.
Corrija seus pontos fracos
O vídeo ajuda a melhorar a pronúncia em inglês, especialmente na articulação de palavras com consoantes densas, como "sediment" (sedimento), "charred" (queimado) e "smouldering" (fumegante). Além disso, a entonação na narração histórica é um ponto chave: frases longas com explicações requerem uma pausa estratégica para manter a clareza. Praticar o shadowing com este trecho ensina a equilibrar a velocidade e a ênfase, evitando a "empacotamento" de palavras. Se você costuma ter dificuldade com a fluência em discursos informativos, este é um recurso excelente para aprender a organizar as ideias de forma natural, como um falante nativo. Lembre-se: aprender inglês com YouTube é uma maneira eficaz de mergulhar no idioma real, e este vídeo é um exemplo perfeito disso.
O que é a Técnica de Shadowing?
Shadowing é uma técnica de aprendizado de idiomas com base científica, originalmente desenvolvida para o treinamento de intérpretes profissionais. O método é simples, mas poderoso: você ouve áudio em inglês nativo e repete imediatamente em voz alta — como uma sombra seguindo o falante com 1-2 segundos de atraso. Pesquisas mostram melhora significativa na precisão da pronúncia, entonação, ritmo, sons conectados, compreensão auditiva e fluência na fala.