Sapiens

by

Yuval Noah Harari

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Human-Caused Ecological Devastation Theme Analysis

Themes and Colors
Foraging, Industry, and Human Happiness Theme Icon
Fiction, Cooperation, and Culture Theme Icon
Science, Wealth, and Empire Theme Icon
Human-Caused Ecological Devastation Theme Icon
LitCharts assigns a color and icon to each theme in Sapiens, which you can use to track the themes throughout the work.
Human-Caused Ecological Devastation Theme Icon

In speculating about humanity’s ancient past, Sapiens author Yuval Noah Harari argues that humans are the Earth’s deadliest species. Harari thinks humanity’s ancestors, Homo sapiens, evolved advanced cognitive skills so suddenly that they jumped to the top of the food chain before the rest of the ecosystem had to time to recalibrate to the new threat. Harari contends that Homo sapiens killed off at least six other human species (including Neanderthals), drove more animal species to extinction than any other creature on Earth, and, in modern times, continues to inflict mass cruelty on other animals through the farming industry. Harari concludes that whenever humans spread into a new territory, death and cruelty follow for other animals. Harari suggests that if humans don’t curb our cruel and dominating tendencies, we might one day be the only animals left. Harari concludes with a warning for humanity to curb our reckless domination of other species and think more carefully about the devastating effect we have on Earth’s ecosystem.

According to Harari, Homo sapiens have been responsible for the extinction of nearly all large mammals on Earth for over 70,000 years, showing that we’ve been the world’s deadliest species. When Homo sapiens evolved new cognitive capabilities around 70,000 years ago (the Cognitive Revolution) and began spreading around the globe, they drove at least six other human species (including Neanderthals) to extinction. Harari contends that our ancestors displaced and killed off even the mammals that were most like us, showing that our human species is deadly and combative.

Harari argues that there’s a pattern in history: every time Homo sapiens shows up in new territory, large mammals go extinct, suggesting that we are responsible for the most extinctions than any other creature on Earth. Harari thinks the Cognitive Revolution happened so suddenly that other animals didn’t have time to develop the instinct to avoid Homo sapiens. Many large mammals in isolated ecosystems—like Australia’s—didn’t fear animals that were smaller than them, because they hadn’t had exposure to small, deadly animals before, leaving them unprepared for the havoc that Homo sapiens would wreak on their species when they first arrived in Australia 45,000 years ago. Homo sapiens ended up killing off 23 out of 24 of Australia’s large marsupial mammals within a few thousand years, suggesting our ancestors were nature’s deadliest threat in that ecosystem. Australia’s mass extinctions weren’t an isolated incident: mass extinction of large mammals also followed in other ecosystems when Homo sapiens spread to those areas, including the Americas (14,000 years ago), the Caribbean (7,000 years ago), and Madagascar (1,500 years ago). To Harari, the evidence shows that ancient Homo sapiens were “ecological serial killers,” as they swiftly became the deadliest animals in every environment they inhabited.

Harari thinks that modern humans are even more deadly and cruel to other species than our ancient ancestors were, citing continued extinctions in the wild and cruelty in the farming industry. He warns against continuing on this path, suggesting that humankind could soon be the only animals left. Harari argues that humans continue to cause extinctions as they spread further into the Earth’s ecosystems. He thinks the “large animals of the oceans” are next, because “many of them are on the brink of extinction now as a result of industrial pollution and human overuse of oceanic resources.” Harari predicts that at the current pace of oceanic pollution, “whales, sharks, tuna and dolphins will follow the diprotodons, ground sloths and mammoths to oblivion.” Harari thus stresses that in pursuing our own interests, humans are having a devastating and irreversible impact on the planet. Harari thinks it’s a mistake to assume that other species (notably agricultural animals including cows, pigs, and chickens) are thriving in numbers as a result of human industry. He contends that although their populations have never been so large, their lives have also never been so short or miserable. For example, chickens can live for up to 15 years roaming in the wild, but most chickens today are only alive for a few weeks in cages before they’re killed for meat. Harari argues that modern humans are not only deadly, but also pathologically cruel to other animal species on Earth, making us even worse than our archaic ancestors. Harari concludes that humanity’s track record with other animal species is deplorable, and he predicts that eventually, there’ll be no large animals left except “humans themselves, and the farmyard animals that serve as [our] slaves.” Harari thus warns humanity about the dangers of our unchecked domination of other species, arguing we’ll regret our actions when we’re the only large animals left on Earth.

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Human-Caused Ecological Devastation Quotes in Sapiens

Below you will find the important quotes in Sapiens related to the theme of Human-Caused Ecological Devastation.
Chapter 4 Quotes

[T]he historical record makes Homo sapiens look like an ecological serial killer.

Related Characters: Yuval Noah Harari (speaker)
Page Number: 67
Explanation and Analysis:

If things continue at the present pace, it is likely that whales, sharks, tuna and dolphins will follow the diprotodons, ground sloths and mammoths to oblivion. Among all the world’s large creatures, the only survivors of the human food will be humans themselves, and the farmyard animals that serve as galley slaves in Noah Ark.

Related Characters: Yuval Noah Harari (speaker), Noah
Related Symbols: Human Flood
Page Number: 74
Explanation and Analysis:
Chapter 5 Quotes

Over the last few decades, we have invented countless time-saving devices that are supposed to make life more relaxed—washing machines, vacuum cleaners, dishwashers, telephones, mobile phones, computers, email. Previously it took a lot of work to write a letter, address and stamp an envelope, and take it to the mailbox. It took days or weeks, maybe even months, to ger a reply. Nowadays I can dash off an email, send it halfway around the globe, and (if my addressee is online) receive a reply a minute later. I’ve saved all that trouble and time, but do I live a more relaxed life?

Related Characters: Yuval Noah Harari (speaker)
Page Number: 87-88
Explanation and Analysis:

Domesticated chickens and cattle may well be an evolutionary success story, but they are also among the most miserable creatures that ever lived. The domestication of animals was founded on a series of brutal practices that only became crueller with the passing of the centuries. The natural lifespan of wild chickens is about seven to twelve years, and of cattle about twenty to twenty-five years. In the wild, most chickens and cattle died long before that, but they still had a fair chance of living for a respectable number of years. In contrast, the vast majority of domesticated chickens and cattle are slaughtered at the age of between a few weeks and a few months, because this has always been the optimal slaughtering age from an economic perspective.

Related Characters: Yuval Noah Harari (speaker)
Page Number: 93
Explanation and Analysis:
Chapter 17 Quotes

Follow-up research showed that Harlow’s orphaned monkeys grew up to be emotionally disturbed even though they had received all the nourishment they required.

Related Characters: Yuval Noah Harari (speaker), Harry Harlow
Page Number: 345
Explanation and Analysis:
Afterword Quotes

Unfortunately, the Sapiens regime on earth has so far produced little that we can be proud of. We have mastered our surroundings, increased food production, built cities, established empires and created far-flung trade networks. But did we decrease the amount of suffering in the world? Time and again, massive increases in human power did not necessarily improve the well-being of individual Sapiens, and usually caused immense misery to other animals.

Related Characters: Yuval Noah Harari (speaker)
Page Number: 415
Explanation and Analysis: