Cover image for Sapiens
Title:
Sapiens

A Brief History of Humankind
Author:
Harari, Yuval Noah
Subject:
History
Science
Nonfiction
Description:
New York Times BestsellerA Summer Reading Pick for President Barack Obama, Bill Gates, and Mark Zuckerberg From a renowned historian comes a groundbreaking narrative of humanity's creation and evolution—a #1 international bestseller—that explores the ways in which biology and history have defined us and enhanced our understanding of what it means to be "human."One hundred thousand years ago, at least six different species of humans inhabited Earth. Yet today there is only one—homo sapiens. What happened to the others? And what may happen to us?Most books about the history of humanity pursue either a historical or a biological approach, but Dr. Yuval Noah Harari breaks the mold with this highly original book that begins about 70,000 years ago with the appearance of modern cognition. From examining the role evolving humans have played in the global ecosystem to charting the rise of empires, Sapiens integrates history and science to reconsider accepted narratives, connect past developments with contemporary concerns, and examine specific events within the context of larger ideas.Dr. Harari also compels us to look ahead, because over the last few decades humans have begun to bend laws of natural selection that have governed life for the past four billion years. We are acquiring the ability to design not only the world around us, but also ourselves. Where is this leading us, and what do we want to become?Featuring 27 photographs, 6 maps, and 25 illustrations/diagrams, this provocative and insightful work is sure to spark debate and is essential reading for aficionados of Jared Diamond, James Gleick, Matt Ridley, Robert Wright, and Sharon Moalem.
Publisher:
HarperCollins

HarperCollins e-books
Date:
2015/02/10
Digital Format:
Adobe EPUB

HTML

Kindle
Language:
English

Summary

Summary

New York Times Bestseller

A Summer Reading Pick for President Barack Obama, Bill Gates, and Mark Zuckerberg

From a renowned historian comes a groundbreaking narrative of humanity's creation and evolution--a #1 international bestseller--that explores the ways in which biology and history have defined us and enhanced our understanding of what it means to be "human."

One hundred thousand years ago, at least six different species of humans inhabited Earth. Yet today there is only one--homo sapiens. What happened to the others? And what may happen to us?

Most books about the history of humanity pursue either a historical or a biological approach, but Dr. Yuval Noah Harari breaks the mold with this highly original book that begins about 70,000 years ago with the appearance of modern cognition. From examining the role evolving humans have played in the global ecosystem to charting the rise of empires, Sapiens integrates history and science to reconsider accepted narratives, connect past developments with contemporary concerns, and examine specific events within the context of larger ideas.

Dr. Harari also compels us to look ahead, because over the last few decades humans have begun to bend laws of natural selection that have governed life for the past four billion years. We are acquiring the ability to design not only the world around us, but also ourselves. Where is this leading us, and what do we want to become?

Featuring 27 photographs, 6 maps, and 25 illustrations/diagrams, this provocative and insightful work is sure to spark debate and is essential reading for aficionados of Jared Diamond, James Gleick, Matt Ridley, Robert Wright, and Sharon Moalem.


Author Notes

Yuval Noah Harari received a PhD in history from the University of Oxford. He lectures at the Hebrew University of Jerusalem, specializing in world history. He has written several books including Sapiens: A Brief History of Humankind which became a 2016 New York Times Bestsellers.

(Bowker Author Biography)


Reviews 7

Publisher's Weekly Review

Writing with wit and verve, Harari, professor of history at the Hebrew University of Jerusalem, attempts to explain how Homo sapiens came to be the dominant species on Earth as well as the sole representative of the human genus. He notes that from roughly two million years ago until about 10,000 years ago, we were not the only humans on the planet; many species preceded us, and some overlapped our tenure. Harari argues persuasively that three revolutions explain our current situation. The first, the cognitive revolution, occurred approximately 70,000 years ago and gave us "fictive" language, enabling humans to share social constructs as well as a powerful "imagined reality" that led to complex social systems. The second, the agricultural revolution, occurred around 12,000 years ago and allowed us to settle into permanent communities. The third, the scientific revolution, began around 500 years ago and allowed us to better understand and control our world. Throughout, Harari questions whether human progress has led to increased human happiness, concluding that it's nearly impossible to show that it has. Harari is provocative and entertaining but his expansive scope only allows him to skim the surface. (Feb.) (c) Copyright PWxyz, LLC. All rights reserved.


Booklist Review

*Starred Review* It's not often that a book offers readers the possibility to reconsider, well, everything. But that's what Harari does in this sweeping look at the history of humans. Beginning before the beginning of Homo sapiens, the book introduces the other members of the genus Homo, who have lived on the planet for millions of years, and shows how sapiens endured while others died out. Then, with both wit and intellectual heft, Harari moves briskly through the important stages of human development: the harnessing of fire, the emergence of language, the agricultural revolution, the ongoing development of religion, the emergence of commerce and empires, and the industrial and scientific revolutions. He then discusses where humans are today and where (if anywhere) they may be tomorrow. There is something to ponder on almost every page. Particularly fascinating is Harari's consideration of whether people were happier in the past, when they had less but expected little, or today, when possibilities are endless but expectations are often not met. Part of the book's genius is not only that it organizes human history into understandable patterns, but also that those patterns are so fresh and fascinating. For instance, there is the idea that the way society has kept itself organized is through the use of fictions religion, obviously, but the idea applies equally to the concepts of money, laws, and human rights: None of these things exists outside the stories that people invent and tell one another. This ability to believe in fictions has also allowed sapiens to give loyalty to everything from nations to corporations. Readers of every stripe should put this at the top of their reading lists. Thinking has never been so enjoyable.--Cooper, Ilene Copyright 2015 Booklist


New York Review of Books Review

SAPIENS: A Brief History of Humankind, by Yuval Noah Harari. (Harper Perennial, $22.99.) Harari, an Israeli historian, delves into humanity's history, exploring why Homo sapiens - once just one human species among several - dominated. This sweeping account attempts to tell a genetic, cultural and social history, with a particular focus on the roles of cognition and agricultural and scientific advancements in our evolution. MEN WITHOUT WOMEN: Stories, by Haruki Murakami. Translated by Philip Gabriel and Ted Goossen. (Vintage, $16.) In these seven tales, emotionally adrift men long for the women they love; one story compares the experience to "a pastelcolored Persian carpet." Our reviewer, Jay Fielden, praised the "rainy Tokyo of unfaithful women, neat single malt, stray cats, cool cars and classic jazz played on hi-fi setups." WRESTLING WITH HIS ANGEL: The Political Life of Abraham Lincoln, Volume II, 1849-1856, by Sidney Blumenthal. (Simon & Schuster, $18.) By 1849, Lincoln's only term as a representative comes to an undistinguished end. The second installment of this biography follows Lincoln as he clashed with his rival, Stephen A. Douglas, who advanced policies that helped expand slavery; eked out a political future; and aligned with the Republicans. THE BURNING GIRL, by Claire Messud. (Norton, $15.95.) Julia and Cassie, two teenagers in Massachusetts, have been best friends since nursery school, but as they edge into adolescence the friendship begins to unravel. Messud is skilled at capturing the perils and rites of passage that come with being a teenage girl, along with the intimacies and heartbreak of female friendships. Ultimately, the book is "a story about stories - their power, necessity and inevitable artifice," our reviewer, Laura Lippman, wrote. WHY WE SLEEP: Unlocking the Power of Sleep and Dreams, by Matthew Walker. (Scribner, $17.) Walker, who directs Berkeley's Center for Human Sleep Science, sees our societal sleep deficit as "the greatest public health challenge we face in the 21st century." The virtues of sleep, he says - everything from better memory retention to the ability to overcome negative feelings - can dramatically improve your life. MY ABSOLUTE DARLING, by Gabriel Tallent. (Riverhead, $16.) Fourteen-year-old Turtle is growing up feral in Northern California, raised by her father to be a self-reliant survivalist. Her world is limited to school, where she's an outcast, and home, where her father trains her and preys upon her. A romance offers an escape, and she must use the skills she learned from her father against him in a fight for her freedom.


Choice Review

In this well-written, fascinating study of the human saga--from the earliest members of the genus Homo until the present day--Harari (Hebrew Univ. of Jerusalem) discusses the major factors that influenced the course of human history. In particular, he considers the importance of the cognitive, agricultural, industrial, and scientific revolutions and ways these pivotal points in history shaped human culture, society, and humans' impact on the world around them. The book emphasizes the overall influence of these major turning points in human history on the development of religion, nations/empires, economic systems, government bureaucracies, imperialist aggression, and the growth of a global human society--and on whether they "set humankind on the road to prosperity and progress" or "led to perdition." The author also offers a sobering vision of humanity's future, one based on the growing capacity to implement evolutionary change based on intelligent design. His insightful, informative discussion on these facets of human history offers considerable food for thought. Harari writes in a clear, conversational tone, with little reliance on jargon or needlessly complicated concepts. This book will be of considerable interest to students of history, anthropology, and human culture. Summing Up: Essential. All library collections. --Danny A. Brass, independent scholar


Guardian Review

Human beings (members of the genus Homo) have existed for about 2.4m years. Homo sapiens, our own wildly egregious species of great apes, has only existed for 6% of that time - about 150,000 years. So a book whose main title is Sapiens shouldn't be subtitled "A Brief History of Humankind". It's easy to see why Yuval Noah Harari devotes 95% of his book to us as a species: self-ignorant as we are, we still know far more about ourselves than about other species of human beings, including several that have become extinct since we first walked the Earth. The fact remains that the history of sapiens - Harari's name for us - is only a very small part of the history of humankind. Can its full sweep be conveyed in one fell swoop - 400 pages? Not really; it's easier to write a brief history of time - all 14bn years - and Harari also spends many pages on our present and possible future rather than our past. But the deep lines of the story of sapiens are fairly uncontentious, and he sets them out with verve. For the first half of our existence we potter along unremarkably; then we undergo a series of revolutions. First, the "cognitive" revolution: about 70,000 years ago, we start to behave in far more ingenious ways than before, for reasons that are still obscure, and we spread rapidly across the planet. About 11,000 years ago we enter on the agricultural revolution, converting in increasing numbers from foraging (hunting and gathering) to farming. The "scientific revolution" begins about 500 years ago. It triggers the industrial revolution, about 250 years ago, which triggers in turn the information revolution, about 50 years ago, which triggers the biotechnological revolution, which is still wet behind the ears. Harari suspects that the biotechnological revolution signals the end of sapiens: we will be replaced by bioengineered post-humans, "amortal" cyborgs, capable of living forever. This is one way to lay things out. Harari embeds many other momentous events, most notably the development of language: we become able to think sharply about abstract matters, cooperate in ever larger numbers, and, perhaps most crucially, gossip. There is the rise of religion and the slow overpowering of polytheisms by more or less toxic monotheisms. Then there is the evolution of money and, more importantly, credit. There is, connectedly, the spread of empires and trade as well as the rise of capitalism. Harari swashbuckles through these vast and intricate matters in a way that is - at its best - engaging and informative. It's a neat thought that "we did not domesticate wheat. It domesticated us." There was, Harari says, "a Faustian bargain between humans and grains" in which our species "cast off its intimate symbiosis with nature and sprinted towards greed and alienation". It was a bad bargain: "the agricultural revolution was history's biggest fraud". More often than not it brought a worse diet, longer hours of work, greater risk of starvation, crowded living conditions, greatly increased susceptibility to disease, new forms of insecurity and uglier forms of hierarchy. Harari thinks we may have been better off in the stone age, and he has powerful things to say about the wickedness of factory farming, concluding with one of his many superlatives: "modern industrial agriculture might well be the greatest crime in history". He accepts the common view that the fundamental structure of our emotions and desires hasn't been touched by any of these revolutions: "our eating habits, our conflicts and our sexuality are all a result of the way our hunter-gatherer minds interact with our current post-industrial environment, with its mega-cities, airplanes, telephones and computers . . . Today we may be living in high-rise apartments with over-stuffed refrigerators, but our DNA still thinks we are in the savannah." He gives a familiar illustration - our powerful desires for sugar and fat have led to the widespread availability of foods that are primary causes of unhealthiness and ugliness. The consumption of pornography is another good example. It's just like overeating: if the minds of pornography addicts could be seen as bodies, they would look just like the grossly obese. At one point Harari claims that "the leading project of the scientific revolution" is the Gilgamesh Project (named after the hero of the epic who set out to destroy death): "to give humankind eternal life" or "amortality". He is sanguine about its eventual success. But amortality isn't immortality, because it will always be possible for us to die by violence, and Harari is plausibly sceptical about how much good it will do us. As amortals, we may become hysterically and disablingly cautious (Larry Niven develops the point nicely in his description of the "Puppeteers" in the Ringworld science fiction novels). The deaths of those we love may become far more terrible. We may grow weary of all things under the sun - even in heaven (see the last chapter of Julian Barnes's A History of the World in 10 1/2 Chapters). We may come to agree with JRR Tolkien's elves, who saw mortality as a gift to human beings that they themselves lacked. We may come to feel what Philip Larkin felt: "Beneath it all, desire of oblivion runs." Even if we put all these points aside, there's no guarantee that amortality will bring greater happiness. Harari draws on well-known research that shows that a person's happiness from day to day has remarkably little to do with their material circumstances. Certainly money can make a difference - but only when it lifts us out of poverty. After that, more money changes little or nothing. Certainly a lottery winner is lifted by her luck, but after about 18 months her average everyday happiness reverts to its old level. If we had an infallible "happyometer", and toured Orange County and the streets of Kolkata, it's not clear that we would get consistently higher readings in the first place than in the second. This point about happiness is a persistent theme in Sapiens. When Arthur Brooks (head of the conservative American Enterprise Institute) made a related point in the New York Times in July, he was criticised for trying to favour the rich and justify income inequality. The criticism was confused, for although current inequalities of income are repellent, and harmful to all, the happiness research is well confirmed. This doesn't, however, prevent Harari from suggesting that the lives lived by sapiens today may be worse overall than the lives they lived 15,000 years ago. Much of Sapiens is extremely interesting, and it is often well expressed. As one reads on, however, the attractive features of the book are overwhelmed by carelessness, exaggeration and sensationalism. Never mind his standard and repeated misuse of the saying "the exception proves the rule" (it means that exceptional or rare cases test and confirm the rule, because the rule turns out to apply even in those cases). There's a kind of vandalism in Harari's sweeping judgments, his recklessness about causal connections, his hyper-Procrustean stretchings and loppings of the data. Take his account of the battle of Navarino. Starting from the fact that British investors stood to lose money if the Greeks lost their war of independence, Harari moves fast: "the bond holders' interest was the national interest, so the British organised an international fleet that, in 1827, sank the main Ottoman flotilla in the battle of Navarino. After centuries of subjugation, Greece was finally free." This is wildly distorted - and Greece was not then free. Harari hates "modern liberal culture", but his attack is a caricature and it boomerangs back at him. Liberal humanism, he says, "is a religion". It "does not deny the existence of God"; "all humanists worship humanity"; "a huge gulf is opening between the tenets of liberal humanism and the latest findings of the life sciences". This is silly. It's also sad to see the great Adam Smith drafted in once again as the apostle of greed. Still, Harari is probably right that "only a criminal buys a house . . . by handing over a suitcase of banknotes" - a point that acquires piquancy when one considers that about 35% of all purchases at the high end of the London housing market are currently being paid in cash. 456pp, Harvill Secker, pounds 25 To order Sapiens for pounds 18.99 with free UK p&p call Guardian book service on 0330 333 6846 or go to guardianbookshop.co.uk. - Galen Strawson Caption: Captions: The biotechnological revolution suggests our replacement by post-humans [Noah Harari] swashbuckles through these vast and intricate matters in a way that is - at its best - engaging and informative. It's a neat thought that "we did not domesticate wheat. It domesticated us." There was, Harari says, "a Faustian bargain between humans and grains" in which our species "cast off its intimate symbiosis with nature and sprinted towards greed and alienation". It was a bad bargain: "the agricultural revolution was history's biggest fraud". More often than not it brought a worse diet, longer hours of work, greater risk of starvation, crowded living conditions, greatly increased susceptibility to disease, new forms of insecurity and uglier forms of hierarchy. Harari thinks we may have been better off in the stone age, and he has powerful things to say about the wickedness of factory farming, concluding with one of his many superlatives: "modern industrial agriculture might well be the greatest crime in history". At one point Harari claims that "the leading project of the scientific revolution" is the Gilgamesh Project (named after the hero of the epic who set out to destroy death): "to give humankind eternal life" or "amortality". He is sanguine about its eventual success. But amortality isn't immortality, because it will always be possible for us to die by violence, and Harari is plausibly sceptical about how much good it will do us. As amortals, we may become hysterically and disablingly cautious (Larry Niven develops the point nicely in his description of the "Puppeteers" in the Ringworld science fiction novels). The deaths of those we love may become far more terrible. We may grow weary of all things under the sun - even in heaven (see the last chapter of Julian Barnes's A History of the World in 10 1/2 Chapters). We may come to agree with JRR Tolkien's elves, who saw mortality as a gift to human beings that they themselves lacked. We may come to feel what Philip Larkin felt: "Beneath it all, desire of oblivion runs." Harari hates "modern liberal culture", but his attack is a caricature and it boomerangs back at him. Liberal humanism, he says, "is a religion". It "does not deny the existence of God"; "all humanists worship humanity"; "a huge gulf is opening between the tenets of liberal humanism and the latest findings of the life sciences". This is silly. It's also sad to see the great Adam Smith drafted in once again as the apostle of greed. Still, Harari is probably right that "only a criminal buys a house . . . by handing over a suitcase of banknotes" - a point that acquires piquancy when one considers that about 35% of all purchases at the high end of the London housing market are currently being paid in cash. - Galen Strawson.


Kirkus Review

Harari (History/Hebrew Univ. of Jerusalem) provides an immersion into the important revolutions that shaped world history: cognitive, agricultural and scientific. The book was originally published in Israel in 2011 and became a best-seller.There is enormous gratification in reading books of this nature, an encyclopedic approach from a well-versed scholar who is concise but eloquent, both skeptical and opinionated, and open enough to entertain competing points of view. As Harari firmly believes, history hinges on stories: some stories for understanding, others prompting people to act cooperatively toward common goals. Of course, these stories" fictions,' social constructs' or imagined realities' "can be humble or evil, inclusive or self-serving, but they hold the power of belief. Harari doesn't avoid the distant past, when humans "were insignificant animals with no more impact on their environment than gorillas, fireflies or jellyfish," but he is a skeptic and rightfully relies on specific source material to support his argumentsthough he is happy to offer conjectures. Harari launches fully into his story with the cognitive revolution, when our brains were rewired, now more intelligent and creative, with language, gossip and myths to fashion the stories that, from politicians to priests to sorcerers, serve to convince people of certain ideas and beliefs. The agricultural revolution ("lives generally more difficult and less satisfying than those of foragers") comes next and firmly establishes the intersubjectivity of imagined orders: hierarchies, money, religion, gender issues, "communication network[s] linking the subjective consciousness of many individuals." Throughout, the author revels in the chaos of history. He discusses the good and bad of empires and science, suggests that modern economic history comes down to a single word ("growth"), rues the loss of familial and societal safety nets, and continues to find wonder in the concept that "the keys to happiness are in the hands of our biochemical system." The great debates of history aired out with satisfying vigor. Copyright Kirkus Reviews, used with permission.


Library Journal Review

Starred Review. This title is one of the exceptional works of nonfiction that is both highly intellectual and compulsively readable. Originally published in Israel in 2011, it has been translated into over 20 languages, including this polished English version. Harari (history, Hebrew Univ. of Jerusalem) takes the reader on a journey that begins with the dawn of Homo sapiens around 200,000 BCE and ends with the scientific revolution. The author covers the cognitive revolution, which allowed Homo sapiens, unlike our predecessors, to imagine what the author terms fictions-gods, laws, the idea of money, and so on. These concepts made it possible for large groups of the species to work together for their greater good. The author goes on to reveal the consequences of the agricultural revolution (beginning around 10,000 BCE) and the scientific revolution in the 16th and 17th century, which include everything from bureaucracy and slavery to the endless search for happiness. VERDICT Although Harari's ideas may be controversial for some readers, those who are interested in history, anthropology, and evolution will find his work a fascinating, hearty read.-Jennifer Stout, Virginia Commonwealth Univ. Lib., Richmond (c) Copyright 2014. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.


Excerpts

Excerpts

Our Brothers' Keepers Despite the benefits of fire, 150,000 years ago humans were still marginal creatures. They could now scare away lions, warm themselves during cold nights, and burn down the occasional forest. Yet counting all species together, there were still no more than perhaps a million humans living between the Indonesian archipelago and the Iberian peninsula, a mere blip on the ecological radar. Our own species, Homo sapiens , was already present on the world stage, but so far it was just minding its own business in a corner of Africa. We don't know exactly where and when animals that can be classified as Homo sapiens first evolved from some earlier type of humans, but most scientists agree that by 150,000 years ago, East Africa was populated by Sapiens that looked just like us. If one of them turned up in a modern morgue, the local pathologist would notice nothing peculiar. Thanks to the blessings of fire, they had smaller teeth and jaws than their ancestors, whereas they had massive brains, equal in size to ours. Scientists also agree that about 70,000 years ago, Sapiens from East Africa spread into the Arabian peninsula, and from there they quickly overran the entire Eurasian landmass. When Homo sapiens landed in Arabia, most of Eurasia was already settled by other humans. What happened to them? Thereare two conflicting theories. The 'Interbreeding Theory' tells a story of attraction, sex and mingling. As the African immigrants spread around the world, they bred with other human populations, and people today are the outcome of this interbreeding. For example, when Sapiens reached the Middle East and Europe, they encountered the Neanderthals. These humans were more muscular than Sapiens, had larger brains, and were better adapted to cold climes. They used tools and fire, were good hunters, and apparently took care of their sick and infirm. (Archaeologists have discovered the bones of Neanderthals who lived for many years with severe physical handicaps, evidence that they were cared for by their relatives.) Neanderthals are often depicted in caricatures as the archetypical brutish and stupid 'cave people', but recent evidence has changed their image. According to the Interbreeding Theory, when Sapiens spread into Neanderthal lands, Sapiens bred with Neanderthals until the two populations merged. If this is the case, then today's Eurasians arenot pure Sapiens. They are a mixture of Sapiens and Neanderthals. Similarly, when Sapiens reached East Asia, they interbred with the local Erectus, so the Chinese and Koreans are a mixture of Sapiens and Erectus. The opposing view, called the 'Replacement Theory' tells a very different story - one of incompatibility, revulsion, and perhaps even genocide. According to this theory, Sapiens and other humans had different anatomies, and most likely different mating habits and even body odours. They would have had little sexual interest in one another. And even if a Neanderthal Romeo and a Sapiens Juliet fell in love, they could not produce fertile children, because the genetic gulf separating the two populations was already unbridgeable. The two populations remained completely distinct, and when the Neanderthals died out, or were killed off, their genes died with them. According to this view, Sapiens replaced all of the previous human populations without merging with them. If that is the case, the lineages of all contemporary humans can be traced back, exclusively, to East Africa, 70,000 years ago. We are all 'pure Sapiens'. A lot hinges on this debate. From an evolutionary perspective, 70,000 years is a relatively short interval. If the Replacement Theory is correct, all living humans have roughly the same genetic baggage, and racial distinctions among them are negligible. But if the Interbreeding Theory is right, there might well be genetic differences between Africans, Europeans and Asians that go back hundreds of thousands of years. This is political dynamite, which could provide material for explosive racial theories.  In recent decades the Replacement Theory has been the common wisdom in the field. It had firmer archaeological backing, and was more politically correct (scientists had no desire to open up the Pandora's box of racism by claiming significant genetic diversity among modern human populations). But that ended in 2010 when the results of a four-year effort to map the Neanderthal genome were published. Geneticists were able to collect enough intact Neanderthal DNA from fossils to make a broad comparison between it and the DNA of contemporary humans. The results stunned the scientific community.  It turned out that 1-4 per cent of the unique human DNA of modern populations in the Middle East and Europe is Neanderthal DNA. That's not a huge amount, but it's significant. A second shock came several months later, when DNA extracted from the fossilised finger from Denisova was mapped. The results proved that up to 6 per cent of the unique human DNA of modern Melanesians and Aboriginal Australians is Denisovan DNA. If these results are valid - and it's important to keep in mind that further research is under way and may either reinforce or modify these conclusions - the Interbreeders got at least some things right. But that doesn't mean that the Replacement Theory is completely wrong. Since Neanderthals and Denisovans contributed only a small amount of DNA to our present-day genome, it is impossible to speak of a 'merger' between Sapiens and other human species. Although differences between them were not large enough to completely prevent fertile intercourse, they were sufficient to make such contacts very rare. How then should we understand the biological relatedness of Sapiens, Neanderthals and Denisovans? Clearly, they were not completely different species like horses and donkeys. On the other hand, they were not just different populations of the same species, like bulldogs and spaniels. Biological reality is not black and white. There are also important grey areas. Every two species that evolved from a common ancestor, such as horses and donkeys, were at one time just two populations of the same species, like bulldogs and spaniels. There must have been a point when the two populations were already quite different from one another, but still capable on rare occasions of having sex and producing fertile offspring. Then another mutation severed this last connecting thread, and they went their separate evolutionary ways. It seems that about 50,000 years ago, Sapiens, Neanderthals and Denisovans were at that borderline point. They were almost, but not quite, entirely separate species. As we shall see in the next chapter, Sapiens were already very different from Neanderthals and Denisovans not only in their genetic code and physical traits, but also in their cognitive and social abilities, yet it appears it was still just possible, on rare occasions, for a Sapiens and a Neanderthal to produce a fertile offspring. So the populations did not merge, but a few lucky Neanderthal genes did hitch a ride on the Sapiens Express. It is unsettling - and perhaps thrilling - to think that we Sapiens could at one time have sex with an animal from a different species, and produce children together. But if the Neanderthals, Denisovans and other human species didn't merge with Sapiens, why did they vanish? One possibility is that Homo sapiens drove them to extinction. Imagine a Sapiens band reaching a Balkan valley where Neanderthals had lived for hundreds of thousands of years. The newcomers began to hunt the deer and gather the nuts and berries that were the Neanderthals' traditional staples. Sapiens were more proficient hunters and gatherers - thanks to better technology and superior social skills - so they multiplied and spread. The less resourceful Neanderthals found it increasingly difficult to feed themselves. Their population dwindled and they slowly died out, except perhaps for one or two members who joined their Sapiens neighbours. Another possibility is that competition for resources flared up into violence and genocide. Tolerance is not a Sapiens trademark. In modern times, a small difference in skin colour, dialect or religion has been enough to prompt one group of Sapiens to set about exterminating another group. Would ancient Sapiens have been more tolerant towards an entirely different human species? It may well be that when Sapiens encountered Neanderthals, the result was the first and most significant ethnic-cleansing campaign in history. Whichever way it happened, the Neanderthals (and the other human species) pose one of history's great what ifs. Imagine how things might have turned out had the Neanderthals or Denisovans survived alongside Homo sapiens . What kind of cultures, societies and political structures would have emerged in a world where several different human species coexisted? How, for example, would religious faiths have unfolded? Would the book of Genesis have declared that Neanderthals descend from Adam and Eve, would Jesus have died for the sins of the Denisovans, and would the Qur'an have reserved seats in heaven for all righteous humans, whatever their species? Would Neanderthals have been able to serve in the Roman legions, or in the sprawling bureaucracy of imperial China? Would the American Declaration of Independence hold as a self-evident truth that all members of the genus Homo are created equal? Would Karl Marx have urged workers of all species to unite? Over the past 10,000 years, Homo sapiens has grown so accustomed to being the only human species that it's hard for us to conceive of any other possibility. Our lack of brothers and sisters makes it easier to imagine that we are the epitome of creation, and that a chasm separates us from the rest of the animal kingdom. When Charles Darwin indicated that Homo sapiens was just another kind of animal, people were outraged. Even today many refuse to believe it. Had the Neanderthals survived, would we still imagine ourselves to be a creature apart? Perhaps this is exactly why our ancestors wiped out the Neanderthals. They were too familiar to ignore, but too different to tolerate. Whether Sapiens are to blame or not, no sooner had they arrived at a new location than the native population became extinct. The last remains of Homo soloensis are dated to about 50,000 years ago. Homo denisova disappeared shortly thereafter. Neanderthals made their exit roughly 30,000 years ago. The last dwarf-like humans vanished from Flores Island about 12,000 years ago. They left behind some bones, stone tools, a few genes in our DNA and a lot of unanswered questions. They also left behind us, Homo sapiens , the last human species. What was the Sapiens' secret of success? How did we manage to settle so rapidly in so many distant and ecologically different habitats? How did we push all other human species into oblivion? Why couldn't even the strong, brainy, cold-proof Neanderthals survive our onslaught? The debate continues to rage. The most likely answer is the very thing that makes the debate possible: Homo sapiens conquered the world thanks above all to its unique language. Excerpted from Sapiens: A Brief History of Humankind by Yuval Noah Harari All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.