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Segmento 1 - complete subtitles

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Coursera - A Brief History of Humankind - Subtitles for Segment 1

Coursera - A Brief History of Humankind - Subtitles for Segment 1

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  • 1. [MUSIC]. About 13 billion years ago, matter, energy, time, and space, came into being in what is known as The Big Bang. The story of this fundamental features of our universe is called physics. Physics examines how matter, energy, time, and space interact with one another and behave. About 300,000 years after their appearance matter and energy started to combine into complex struct, structures which we call atoms. And these atoms then combined into even more complex structures which are called molecules. The story of atoms, molecules, and their interactions is called chemistry. Chemistry examines what happens when an oxygen atom comes into contact with a hydrogen atom or when a solid molecule comes into contact with a water molecule. This is what chemistry does. About 4 billion years ago on a planet called earth certain molecules combined to form even larger and more complex structures which we call organisms, or living creatures. The story of organisms is biology. Biology examines how for example a lion or a giraffe function and what happens when a lion comes into contact with a giraffe. This is biology. About 70,000 years ago, organisms belonging to a very particular specie, our species, Homo sapiens started to come together and combine and form even more elaborate structures, which we call cultures. The development of these human cultures is history. This is what this course will be about, the formation and development and interaction of human cultures from about 70,000 years ago until today. From this perspective, what is essential to realize is that there is no unbridgeable gap between history on the one side, and physics, chemistry, and biology on the other side. History is simply the next stage in the process of ongoing complexity in the universe. We have physical dynamics and then they become more and more complex. We have chemistry, chemical dynamics. And then, chemical dynamics become more and more complex. We have biology, biological dynamics and when biology becomes very, very complex, then we get history. Now, three very important things happened
  • 2. in history. You can, you can summarize the whole of history in just three main revolutions or three main events the first is the cognitive revolution. The cognitive revolution began about 70,000 years ago. In this revolution, Homo sapiens which previously was just an insignificant specie of African ape evolved unique cognitive abilities. Cognitive abilities means thinking, remembering, communicating, learning. These are the cognitive abilities. So Homo sapiens developed unique cognitive abilities that gave it immense power and turned it into the most important animal in the world. So this is the first big revolution of history, the cognitive revolution. The second big revolution of history is the agricultural revolution and it began about 12,000 years ago. During the agricultural revolution, Homo sapiens domesticated certain kinds of animals and plants, established villages and, and, and cities and other permanent settlements and began to create ever more complex societies. Cities and kingdoms and empires and churches and so forth. So this is the second big revolution of history, the agricultural revolution. The third big revolution, revolution of history is the scientific revolution. It began about 500 years ago. And during the scientific revolution, Homo sapiens understood, better and better, the rules that govern the natural world around it and inside it. And thereby, gained more and more power and became the master of the entire planet. It has become so powerful that today it actually begins to change the most basic rules of life. For about 4 billion years life on earth evolved according to the laws of, to the rules of natural selection, evolution by natural selection. And today, Homo sapiens is gaining so much power. Thanks to technologies like genetic engineering and direct brain computer interfaces and so on and so forth, it is expected that in the next century or two, it will really completely change the way that life evolves on planet earth, and in the Universe in general. We will come to speak about this in greater depth. At the end of the course, when we'll discuss revolutions at the ecological and, and, political changes of the 20th
  • 3. and 21st century. What you will do in this course is to survey these three fundamental revolutions of history. The Cognitive revolution, the Agricultural revolution, and the Scientific revolution. And we'll examine what was their impact both upon human beings and upon the fellow organisms and the environment around them. Now, it's very important to realize that humans existed long before history. History began as according to evolution about 70,000 years ago, but animals much like you and me, much like modern humans first appeared about 2 and a half billion years ago in East Africa. However, for most of these 2 and half and billion years our ancestors, our human ancestors were just another kind of animal. There was nothing special about humans. There was no hint that their, great, great, great grandchildren would one day, walk on the moon, or split the atom, or understand DNA, or write history books. The most important thing to know, about prehistoric humans, it it is, that they were unimportant creatures. They did not have more impact upon the world than say gorillas, or fireflies, or penguins. The history of ancient humans was just another chapter in the big book of biology. Now, biologists classify animals into species animals are said to belong to the same species if they tend to have sex with one another to mate with one another, giving birth to fertile offspring. Horses and donkeys for example, they look quite similar and they are indeed very similar in many of their qualities, but horses and donkeys usually, have little sexual interest, one in the other. People sometimes force horses and donkeys to mate and then they even can produce offspring. But their offspring, which are called mules, are always sterile. This shows, that horses and donkeys, despite all the similarities between them, are in fact, two completely different specie. Since, they cannot exchange genes between them, they are evolving, over the generation, in different directions. When there is some important genetic mutation in a horse, it can never pass to donkeys because they can't produce fertile offspring together. So, this is why, they're separate,
  • 4. different species in contrast. A Bulldog and a Cocker Spaniel may look very different from one another, but they will happily mate. They have a lot of sexual interest, one in the other, and when they mate, they can produce fertile puppies that will grow up to mate with other, other dogs, and produce more puppies, and so forth and so on. So this is why Bulldogs and Spaniels are considered members of the same species. They are both dogs. Now, species that evolved from common ancestors, even when they are different from one another like horses and donkeys, still a similar species that evolved from a common ancestor are bunched together by biologist under the heading, under the title genus. This is how scientists called a group of species that evolved from a common ancestor, they call it genus, the plural of genus is genera. For example, lions, tigers, leopards and jaguars are different species within the genus Panthera. It's, also, it's important to know, that scientists usually like to use the Latin language in order to name things, because everything's sounds far more impressive and scientific when you say it in Latin. So, for example, all the medicines we use or the name of the muscles in our bodies are all in Latin. Also, the names of animals, biologists, and plants, and all other organisms, biologists like to use Latin to give animals those scientific name. And the rule is that a scientific name of each animal has two parts. First, the genus, and then the specie. Lions for example, the scientific name of the lion is not lion. When you write in, in, in scientific articles about lions you don't speak about lions, you speak about Panthera leo. This is the scientific name of the lion. Panthera is the name of the genus. It comes first, and then leo, this is the name of the species. It comes second, so lion is Panthera leo. You and me, and I guess everybody who watches this video, we are all a Homo sapiens. This is the scientific name of our species, Homo sapiens, which means the species, sapiens, a Latin word meaning wise, of the genus Homo, a Latin word meaning men. So the meaning of the scientific name Homo sapiens is wise men, this is the name we gave ourselves, we might be very
  • 5. wise but we are not particularly modest. Genera, so this is genus, and genera. The, the, genera is the plural of the word genus. It's quite complicated. Genera in their term are also grouped by biologists into larger collectives which are known as families. So we have in nature, for example the cat family, which includes many, many genera and species of cats like all the lions and cheetahs and house cats, they all belong to the cat family. And we have the dog family, which includes not only dogs but all kinds of wolves and, and foxes, and jackals. They all belong to the big family the dog family. And we have the elephant family, which includes Indian elephants and African elephants, and extinct species of elephants, like mammoth and mastodons. What is important to know is that all members of the family Trace the lineage back to some ancient ancestor who is the great, great, great grandmother or grandfather of all of them. All the cats for example, from the most ferocious lion in the African Savannah to the smallest, cutest, house kitten in your house. They all have the same great, great, great ancestor, who lived about 25 million years ago. So, these are families. Homo sapiens too, our species, belongs to a family. A biological family. This banal fact, used to be one of the most closely guarded secrets of history. For thousands of years, Homo sapiens preferred to view itself as totally different from all the other animals and set apart from all the other animals as a kind of orphan, which has no family, no cousins, no siblings, and most importantlym no parents. As if Homo sapiens just popped up on earth without having any evolutionary ancestors, but that is just not the case. Whether you like it or not, the truth is that we, the species Homo sapiens are also members of a large and particularly noisy family called, the family of great apes. Just as lions and cheetahs belong to the family of cats. So we Homo sapiens have a family called the great apes. There are some other members of this family, which are still living today in the world. Our closest cousins, our closest relatives which are still alive, includes
  • 6. the chimpanzees, the gorillas, and orangutans. Of these, chimpanzees are the closest to us. Just 6 million years ago, if you went back in time 6 million years, you would find somewhere in Africa a single female ape who had two daughters. One of her daughters became the ancestor of all the chimpanzees and the sister, the other daughter, she's yours and mine great, great, great, great, great grandmother. So Homo sapiens belongs to a family. Homo sapiens has kept hidden an even more disturbing secret. We have not only a big family with many cousins. Once upon a time, we also had quite a few brothers and sisters. We, that is Homo sapiens, we tend to call ourselves not Homo sapiens. Usually, when we speak about ourselves, we use the title human as if only us are human we are the only humans. But the fact is that there used to be many other human species on planet Earth. Humans simply means animals that belong to the genus Homo, that is man in Latin. So this humans, they first appeared in East Africa, about 2 and a half million years ago. They did not appear out of nowhere, they evolved from an earlier genus of apes, which is called Australopithecus. It has nothing to do with Australia, this complicated name. It simply means southern ape. so Australopithecus was the ancient ancestor of humans. The first human specie evolved from Australopithecus somewhere in east Africa about 2 and a half million years ago. At first, it was the only human specie, but, about 2 million years ago, some of these archaic men and women left their homeland in east Africa and spread around the world, settling various areas in North Africa, the Middle East Europe and Asia. And in each area, these men and women encountered different conditions, a different climate, different geography, animals and plants. And in order to adapt to these different conditions, the human populations, in each of those areas began to evolve in different ways. And this created, with time, completely different human species. For example, humans who after leaving Africa, reached northern Europe, they needed to adapt to the very cold climate of northern Europe with lots of ice and
  • 7. snow. And all kinds of big animals like birds and mammoth and mastodons. Other humans, after leaving Africa, they eventually ended up in Indonesia and they needed to adapt to the very hot, tropical climate of the jungles and swamps of Indonesia. Other humans, meanwhile, reached central Asia, the deserts of central Asia, and they needed to adapt to survive the very dry climates of central Asia. So the result was that over the years, many, many different species of humans evolved in different parts of the world. And to each of these different human species, scientists have assigned its own pompous Latin name. Now, you don't need to remember the names of the different species and the details that I'm going to tell about the different species. But I would like to take a few minutes to tell you about some of these, of ancient brothers and sisters of ours, some of these ancient human species so that you will know our family a little better. In Europe, in the Middle East a gold uh,specie of humans which scientists call Homo neanderthalensis. This means in Latin, man from the Neander Valley. The name was given because the first remains of these ancient humans were discovered by archaeologists in the Neander Valley in Germany. So they called this species men from the Neander valley, Homo neanderthalensis, but they also gave these humans a nickname, which everybody uses and I will also use, they are the Neanderthals. Neanderthals were well adapted to the cold climate of ice age Europe and the Middle East. Even the Middle East was at that time much colder than it is today. Neanderthals were bigger, more muscular than us. They had insulating layers of fat covering their bodies to give them better protection from the cold and they even had bigger brains that we have. So this was one human specie as it evolved in Europe and the Middle East. In another part of the world, on the island of Java in Indonesia, evolved Homo soloensis. This means, in Latin again, man from the Solo Valley, because the first remains of this human specie were discovered by archaeologists in the Solo Valley on Java Island . And Java had tropical climate so Homo soloensis was evolving over the years to
  • 8. become better and better adapted to living in the jungles and swamps of tropical Java. On another Indonesian island, the very small Island of Flores evolved a very unique and interesting human specie which is called by scientists Homo floresiensis. This means, you can probably now guess it by yourself, man from Flores Island, because this is where this species lived, on Flores Island. Now the unique thing about these humans, about Homo floresiensis is that they were dwarfs, they were very very small. Eh, what happened is, that Flores used to be connected to the mainland eh, by, by land, and at some time, the sea levels rose, the ocean rose, and Flores was disconnected from the mainland. And some people who walked over the land to, to Flores, they got stuck on this island when the, when the sea level rose. And Flores is a small island and there is not much to eat on, on such a small island. So the big people died first the big people need a lot of food, you know, to survive, so they died first. And smaller people who need less food eh, in order to survive, they managed to survive better. And this happened generation after generation, the smallest people had the best chances of having enough food and and and, keeping themselves alive. So over the years, the people who got stuck on Flores Island became smaller, and smaller, and smaller, until they became dwarves. And it's estimated, according to the bones that scientists have found that Homo floresiensis reached a maximum height of no more than one meter and the maximum weight of 25 kilograms. Nevertheless, these tiny people, they still were humans. They're still able to manufacture and use all kinds of tools like spears and so forth. They even managed, at least from time to time, to hunt elephants. Now, it wasn't very big elephants, it was also dwarf elephants, because also, elephants that got stuck on Flores Island the same thing that happened to humans, happened also to the elephants. And they became smaller and smaller and smaller until I, I, Flores was populated by eh, tiny people hunting tiny elephants, so this is Flores. ==
  • 9. 255 While this was happening in the tiny island of Flores, in the big open spaces 256 of Asia, evolved a different human specie, which is called by scientists, 257 Homo erectus. Homo erectus means upright man because 258 this man, these people [sic: were eh, very tall - he should have said: walked erect] . 259 They were taller than us reaching heights of 1.8 and even 1.9 meters tall. 260 Another important fact about Homo erectus is that it was probably the most 261 successful human species ever in terms of how many years it managed to survive. 262 Homo erectus first appeared about, first evolved about 1.5 million years ago and 263 survived until about 50,000 years ago. So Homo erectus, this specie existed for 264 close to 1 and a half million years, in contrast, our species, Homo sapeins, 265 began to evolve maybe 300,000, 200,000 years ago. 266 We [have existed] only about 200 to 300 thousand years. And it is very unlikely that we would 267 break the record of Homo erectus, it's very unlikely, that our species would 268 manage to live for more than 1 and a half million years. 269 In fact, as it would seem in the last lesson of this course, which we will 270 discuss in the future, it is doubt, it is doubtful if we have managed to exist for 271 even a 1000 years, so what to speak of a million and a half years. 272 So this is Homo erectus. In 2010, scientists discovered the 273 remains of another lost brother or lost sister when they excavated the Denisova 274 cave in, in Russia, in eastern Russia. So archaeologists excavating the cave, 275 they made eh, amazing find, amazing discovery. 276 They found there a finger, or not a finger, the found the fossilized bone of 277 a human finger and they managed to extract DNA from this fossilized bone and 278 to map it to see what kind of DNA was, was inside and they compared the DNA from 279 the finger of Denisova cave to the DNA of all other known human species and they 280 didn't match. So they came to the conclusion, based 281 just on this single finger that previously, there existed, at least in 282 central Asia, another specie of humans, which they now called Homo denisova, man 283 from the Denisova Cave. Which was different from the Neanderthals 284 and Homo erectus and and all the rest, so this is Homo denisova. 285 Who knows how many other ancient human species existed in the past and are 286 waiting to be discovered in all kinds of caves and remote islands? 287 We don't know for sure. When all this was happening in Europe and 288 Asia, evolution in East Africa, where humans first emerged did not stop. 289 Evolution continued, natural selection continued to put pressure on humans in 290 east Africa which resulted in the evolution of more, and more human species 291 also in Africa. We have, for example, Homo rudolfensis. 292 Men from Lake Rudolph, whose remains were found near, near Lake Rudolph. 293 We have Homo ergaster, which means working men, because archaeologists 294 discovered alongside the bones of this species, also many, many tools made by 295 these ancient humans, so they called them working men as if they just went around 296 making tools, stone tools all the time. And eventually, our own species, Homo 297 sapiens, also appeared in east Africa, about 200,000 or 300,000 eh, years ago.
  • 10. 298 You don't need to remember the names and details, as I said, of all these 299 different human species. What is important, however, is to realize 300 how they are related to one another or the general picture that, this is more 301 correct. What is important is to understand the 302 general picture of the human family. And the general picture of the human 303 family is that there are many human species and not just one. 304 Some of these species were massive, very big, like Homo erectus and the 305 Neanderthals. Others were dwarfs like Homo 306 floresiensis. Some human species were fearsome hunters. 307 Subsisting mainly by hunting animals. Other human species lived mainly by 308 guttering plants, they are vegetarians. Some human species lived on a single 309 island, like Flores Island or Java Island. 310 Other human species roamed over entire continents, like Homo erectus or Homo 311 denisova, but all of these different human species belong to the genus Homo. 312 They are all human beings. They are all part of the human family. 313 Now, many people have heard that once upon a time there were all kinds of human 314 species on planet Earth. However, we often tend to mistakenly 315 arrange these different species in a straight line of descent. 316 As if we have Homo ergaster that slowly evolved into Homo erectus and then Homo 317 erectus slowly evolved into the Neanderthal and the neanderthals evolved 318 into us. According to this linear model of human 319 evolution at any particular moment in time, there was only one type of human 320 specie inhabiting planet Earth and all previous species of humans were just 321 older models of ourselves. They evolved eventually to become us, but 322 the truth is different. The truth is that from about 2 million 323 years ago until about 10,000 years ago, that world was home at one in the same 324 time to several human species simultaneously and why not? 325 Today, there are many different species of pigs in the world, there are many 326 different species of foxes. There are many different species of 327 bears, like you have you have grizzly bears, and you have Arctic bears, and you 328 have brown bears, and you have black bear. 329 Bears all living together at the same time on planet Earth. 330 So, 100,000 years ago, there were at least six different species of humans 331 living side by side on planet Earth. We know for sure about six, there might 332 have been eh, many more. And this should not surprise us, that in 333 different part of the world, there are different human species at the same time. 334 What is surprising, what is strange, is the current situation that in all the 335 world, there is just one human specie, our specie. 336 You go to Europe. You go to India. 337 You go to China. You go to Australia. 338 You go to America. Everywhere, you encounter just one 339 specie, our specie, Homo sapiens. This is very strange and actually it's a 340 bit suspicious. As we shall shortly see in the next 341 segments of this lesson, Homo sapiens has pretty good reasons to hide the fact, to 342 forget the fact, that it once had brothers and sisters. 343 Because there is some evidence that we, Homo sapiens, had a hand in the 344 disappearance of all the other human species. 345 What exactly happened to the other human species and what we Homo sapiens may have 346 done to them will be discussed in the next segment of this lesson.

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