Previous
Chapter 3
Themes
Key
LitCharts assigns a color and icon to each theme in Sapiens, which you can use to track the themes throughout the work.
Foraging, Industry, and Human Happiness
Fiction, Cooperation, and Culture
Science, Wealth, and Empire
Human-Caused Ecological Devastation
Summary
Analysis
Before the Cognitive Revolution, all species of humans lived in the Afro-Asian landmass. Other land masses, like Australia and Madagascar were completely isolated ecosystems. After the Cognitive Revolution, Sapiens learned how to build boats, and they began exploring farther into the planet’s ecosystems—initially from East Asia to Australia. Harari argues that the moment Sapiens set foot on Australia, they jumped to the top of the food chain and “became the deadliest species ever in the four-billion-year history of life on Earth.” Within a few thousand years, many of Australia’s marsupial species (like giant koalas and marsupial lions) were extinct.
Harari thinks Homo sapiens are the “deadliest species ever” seen in the “history of life on Earth,” because of how many extinctions humans have caused in the last 70,000 years. He notes that every time humanity’s ancestors attempted to spread and settle in new terrain (like Australia), widespread extinctions followed, suggesting that Sapiens act recklessly when they inhabit a new ecosystem. Harari addresses this topic because he worries about the way humans treat the planet (and other animals within its ecosystems), and he wants to warn against continuing on this path.
Themes
Some scholars blame marsupial extinctions on climate change (like ice ages), but Harari thinks Sapiens are responsible, because archaeological evidence suggests ancient marsupials survived many ice ages. In addition, sea life—where Sapiens couldn’t dwell—saw hardly any extinctions in the time period when Sapiens began exploring Australia. In addition, mass extinctions around the globe typically coincide with Sapiens’ arrival on those land masses. New Zealand’s wildlife weathered 45,000 years of climate change, but 60 percent of the birds went extinct after Sapiens first arrived there about 800 years ago. Harari contends that “the historical record makes Homo sapiens look like an ecological serial killer.”
To Harari, scientific records of animal extinctions over the last 70,000 years show a clear correlation between Sapiens arrival in a new territory and evidence of extinctions. He knows that scientific theories involve data and interpretation and the interpretations might be wrong—but in this case, he thinks there’s so much evidence that it’s hard to ignore the correlation. Harari wants to emphasize how much death occurs when humans inhabit an ecosystem to make the reader question why humans continue to act in such destructive ways.
Themes
Some scholars suggest that the mass extinctions happened because Australia’s giant marsupials had no prior exposure to humans and didn’t realize they were a threat (unlike large mammals in Afro-Asia, who’d lived with Sapiens for two million years). Others argue that humans’ use of fire to clear land radically altered Australia’s ecosystem and rendered many species extinct. Some think that climate change did alter Australia’s ecosystem around 45,000 years ago, but it wasn’t able to regain balance with Sapiens in the ecosystem as well. Even though many scholars still blame climate change for such extinctions, Harari thinks Sapiens are ultimately responsible—because mass mammal extinctions in the Americas also align with Sapiens’ arrival, around 16,000 years ago.
As before, Harari highlights several conflicting theories about what caused Australia’s widespread extinctions 45,000 years ago. In doing so, he intends to show that there’s a great deal of speculation involved in scientific theorizing—meaning that prevailing scientific theories might be wrong. He wants to sow doubt about theories that claim Sapiens didn’t cause extinctions so that he can make room for his own view that Sapiens did cause widespread extinctions every time they spread to a new territory. Harari’s keen to push this line of argument because he wants to warn his readers about the dangers of killing off so many animal species, something he thinks modern humans still do.
Themes
Harari concludes that early Sapiens’ global colonization—or the “First Wave Extinction”—was a colossal ecological disaster. Large mammals were most affected, and the only ecosystems spared were those that remained uncolonized until relatively recently, like the Galapagos islands. The “Second Wave extinction” followed with the advent of farming, and modern humans are part of the “Third Wave Extinction” today. Harari thinks the last remaining large mammals on Earth—which are mostly in the oceans—will be next to go, and it saddens him that only humans (and our farmyard animals) might be the only large creatures left on Earth as the “human flood” continues.
Harari suggests that humans never stopped causing widespread ecological damage. He thinks humans act selfishly and recklessly in every ecosystem we inhabit, and that we’ll regret such behavior when there are no other animals left. Harari inverts the metaphor of Noah’s ark to emphasize how destructive humanity’s behavior is towards animal species. In the original Noah’s ark myth in Judeo-Christian traditions, a man named Noah saves two of each animal species on Earth from a global flood by building a giant ark for them. Harari inverts this idea, suggesting that the “flood” is actually humans (not water) and we’re drowning (rather than saving) all the other species alive with our relentless drive for human expansion.
Themes
Get the entire Sapiens LitChart as a printable PDF.
