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There is one case 65 million years ago, at a point in time known as the Cretaceous-Tertiary boundary (K-T boundary), with strong evidence supporting an asteroid impact around the same time the dinosaurs disappeared.

“That one instance really guided everybody’s thinking, and the idea that impacts caused mass extinctions was really, really popular,” said Renne, who wasn’t involved in the Blackburn study.

enne says that even the asteroid impact at the K-T boundary likely only finished the job that major volcanic eruptions in India started. (Related: “What Killed Dinosaurs: New Ideas About the Wipeout.”)

Yes, billions of dinosaur bodies died and fell to the Earth here in this span, and trillions more dinosaur footsteps pressed into the Earth, but hardly a trace remains today. A cryptic smattering of lakeside footprints represents their entire contribution to the Triassic period. A few bones and footsteps miraculously preserved in New England and Nova Scotia are all that remains from the entire 27-million-year Early Jurassic epoch. No trace of dinosaurs remains whatsoever from the 18-million-year Late Jurassic. A handful of bones from one layer in Maryland represents the entire 45-million-year Early Cretaceous; the Late Cretaceous gives up a Hadrosaurus in New Jersey, and part of a tyrannosaur in Alabama, but mostly comprises unimpressive fragments of bone and teeth that cover the remaining 34 million years of the Earth’s most storied age, until doomsday

So that’s what 180 million years of complete dominance buys you in the fossil record. What, then, will a few decades of industrial civilization get us? This is the central question of the Anthropocene—an epoch that supposedly started, not tens of millions of years ago, but perhaps during the Truman administration

as the example of the dinosaurs shows, the chance that any city-swallowing delta deposit from a window of time only a few centuries wide would be lucky enough to be not only buried and preserved for safekeeping, but then subsequently not destroyed—in the ravenous maw of a subduction zone, or sinking too close to the cleansing metamorphic forge of Earth’s mantle, or mutilated in some m

there exists a better word in geology than epoch to describe our moment in the sun thus far: event. Indeed, there have been many similarly disruptive, rapid, and unusual episodes scattered throughout Earth history—wild climate fluctuations, dramatic sea-level rises and falls, global ocean-chemistry disasters, and biodiversity catastrophes

we’re very likely to return to our regularly scheduled programming and dive back into a punishing Ice Age in the next half-million years. This means that sea level—after shooting up in the coming millennia by our own hand, and potentially burying coastal settlements in sediment (good for fossilization)—will eventually fall hundreds of feet below where it is today, and subject the shallow continental shelves, along with our once submerged cities and magnificent seams of garbage, to the cold winds of erosion (bad for fossilization), where they’ll be mostly reduced to nothing

What else of us could be sampled from this sliver of deep-sea-muck-turned-rock—these Anthropocene clays and shale layers? Pass it through a mass spectrometer and you would see, encoded in its elements, the story of the entire planet in this strange interval, the Great Derangement of the Earth’s systems by civilization. You would see our lightning-fast injection of hundreds of gigatons of light carbon into the atmosphere written in the strange skew of carbon isotopes in this rock—as you do in rocks from the many previous carbon-cycle disasters of Earth history. The massive global-warming pulse created by this carbon disaster would be written in oxygen isotope

The sulfur, nitrogen, thallium, and uranium isotopes in these rocks (to mention just a few) would whisper to you—again, in squiggles on a graph—that the global ocean lost much of its oxygen during this brief but enigmatic interval. Strontium isotopes would tell you that rock weathering dramatically accelerated worldwide for a few tens of thousands of years as sweltering, violent storms attacked the rocks and wore down the continents during a brief, CO2-driven fever.

The most enduring geological legacy, instead, will be the extinctions we cause. The first wave of human-driven extinctions, and the largest hit to terrestrial megafauna since the extinction of the dinosaurs, began tens of thousands of years ago, as people began to spread out into new continents and islands, wiping out everything we tend to think of as “Ice Age” faun

nd then, after all that, find itself, at a given point in the far future, fantastically lucky enough to have been serendipitously pushed up just enough so as to be exposed at the surface, but not too high as to have been quickly destroyed by erosion … is virtually ni

The first major mass extinction, 445 million years ago, took place in multiple pulses across a million years. An event. The second major mass extinction, 70 million years later, took place over 600,000 years—400,000 years longer than the evolutionary history of Homo sapiens.

The idea of the Anthropocene inflates our own importance by promising eternal geological life to our creations. It is of a thread with our species’ peculiar, self-styled exceptionalism—from the animal kingdom, from nature, from the systems that govern it, and from time itself. This illusion may, in the long run, get us all killed.