I’m finally heeding all the recommendations and reading Yuval Noah Harari’s Sapiens: A Brief History of Humankind. Harari is an excellent writer, and though at times he seems to present some unproven hypotheses as proven fact, and nine years after initial publication some of the information feels a bit dated, he makes up for it by making the story of humanity read like an epic saga across the millenia.
So far, I’ve only read the first section: The Cognitive Revolution, which goes over what is known about pre-agricultural humanity. Harari is clear on how little we actually do know about the cultures of prehistoric hunter gatherers, except to note that they were probably very diverse.
What is clear however, is how Homo sapiens spread out of African some 60,000-70,000 years ago and subsequently throughout the globe. Of note, earlier human species, such as Homo erectus, the Neanderthals, and Denisovans, had spread throughout Eurasia, but none had made it to Australia, the Americas, or the hundreds of islands Homo sapiens would eventually inhabit.
What’s striking is what happens in the paleontological record once Homo sapiens enter a region. We’ve discussed before that Neanderthals in a particular region disappear within a few millenia after Homo sapiens show up. What’s been less discussed is the overall large wave of extinction in megafauna, large animals, that takes place once Homo sapiens move in.
It’s particularly striking in places like Australia, the Americas, and island habitats. Animals such as six foot kangaroos, marsupial lions, giant koalas, dragon-like lizards, mammoths, mastodons, bear-sized rodents, and a variety of other creatures all disappear within a few millenia after Homo sapiens arrive. In Eurasia, earlier human species had existed for over a million years, and the animals had already learned to avoid human shaped creatures. But the animals beyond Africa and Eurasia didn’t have the chance to evolve that fear before they were gone.
Some researchers have tried to blame the extinctions on climate change, but as Harari discusses, the climate is always changing, yet it’s a consistent pattern that species that had survived for millions of years disappear in a region shortly after Homo sapiens come on the scene.
None of this is to say that the prehistorical humans entering these areas were being immoral with their actions. They were simply hunting the available food. They didn’t have a comprehensive view the ecosystem. There were no written records. The population of particular animals species probably didn’t drop that much in any one person’s lifetime. And by the time the last of a species were killed off, they would have been very rare, with the person killing that last member of a species unaware of the significance of what they were doing.
It’s only recently that we’ve come to appreciate our effect on those ecosystems, and the danger of species extinction. Which means we shouldn’t take comfort from the fact that we’re just continuing what our forebears have always done. They didn’t understand what they were doing. We don’t have that excuse.