My rating: 5 of 5 stars
Consider the Neanderthal.
According to Elizabeth Kolbert’s “The Sixth Extinction,” they had many similarities with modern humans. They buried their dead. They wore clothing and lived in built shelters. They were hairless in the way humans are. They cared for one another.
And we hastened their extinction.
We’ve done that a lot, we members of H. sapiens. Sometimes we did so directly, by hunting various animals and birds into extinction. Other times our influence has been indirect, particularly in the modern industrial age, when our migration patterns, use of fossil fuels and general disregard for the natural environment has erased many species. It’s no wonder that many geologists now think of this era as the Anthropocene, named after the impact we humans have had.
But the Earth is 4.5 billion years old. It has been here far, far longer than we have – and will be here far, far longer than we will be. In those billions of years, it’s seen five major extinction events. One of them, believed to be a meteor strike, killed off the dinosaurs. The only difference in what may be an eventual sixth extinction is that we seem to be doing it to ourselves, whether through the slow buildup of atmospheric change or – though it’s hopefully avoidable – itchy nuclear trigger fingers.
I picked up “The Sixth Extinction” because I was an admirer of Kolbert’s New Yorker articles on the subject. And yet the book wasn’t as downbeat as I thought. At worst it takes the geologist’s long view – that we’re here for a moment, and even if we make the best of things, this planet has seen many changes and we’re almost certainly going to be one of them.
And at best it’s actually hopeful. Sure, we’ve caused a lot of damage, but at least we’re aware of it and could adapt – or even change its progress.
Still, we’ve done a bang-up job in screwing things up. For all the talk of climate change in terms of air temperature, perhaps the most powerful chapters are about the oceans. The pH of our vast waters is changing, and that’s meant the decay of coral reefs and the disappearance of sea creatures dependent on just the right chemical content. So much of the food chain is dependent on calcifiers, species that build the structures other species are dependent on. With the growing acidification of the seas, that ability is being literally eaten away.
“Lab experiments have indicated that calcifiers will be particularly hard-hit by falling ocean pH, and the list of the disappeared at Castello Aragonese confirms this,” Kolbert writes. “In the pH 7.8 zone, three-quarters of the missing species are calcifiers.”
Forget about the proverbial canary in the coal mine; try the calcifiers in the sea.
At least “The Sixth Extinction,” like Alan Weisman’s “The World Without Us,” is an engaging read. Kolbert is a fine writer and terrific guide to planetary decline, mixing in geology, paleontology, chemistry and good old travel writing in equal measure. I learned something on almost every page.
I was particularly struck by her description of why the Neanderthals no longer exist: Among other things, they apparently lacked a curiosity gene that humans have. While Homo sapiens came out of Africa and traveled the world – sailing uncharted seas and moving into unknown lands – Neanderthals, it seems, didn’t leave their home places. Humans who encountered them probably mated with them, in fact, and carried those genes on our travels. Genetics has shown that most of us are between 1 and 4 percent Neanderthal.
So, though pure Neanderthals are gone from this planet, they’re not gone from our DNA. We’re just a bunch of mutts, we humans. Take that, racists!
Humans still have an uphill battle in maintaining the Earth. Even if we can stop our profligate ways, there’s still the risk of a hit of space debris, an explosion from the planet’s interior, or the literal fallout from a nuclear war. Still, if anything sentient survives into the next millennia, I hope a copy of “The Sixth Extinction” is around to be read by them. And I hope they learn as much as I did.