We left Earth to its own devices for long enough, it would eventually enter another ice age. This would be much more extreme than the kinds of climate changes we are potentially facing now. During the...
This way, we’ve changed the geometry of the planet. Before we came along, the world was discontinuous. Oceans, deserts, and mountain ranges formed impenetrable barriers, breaking Earth into separate r...
Yet among the multiple animal inventions at the dawn of the Cambrian were new forms of mobility. A number of critters began burrowing into these mats and braving the toxic soils beneath them. These di...
While ruthlessly aggressive toward other species, they are also unusually cooperative with their own kind. Ants from neighboring nests don’t fight, as with other species,
What was the question again? Is it when human activity first became detectable in the geological record? When humans first left a clear global marker, or golden spike? When human-induced change to the...
We need visions of a future in which we have applied our infinite creativity to the task of living on a finite world, where we have embraced our role, become comfortable and proficient as planet-shape...
We are already behaving differently from that bacterial colony in a petri dish, deviating from the fatal S-curve, using our limited but growing global cognitive capacities to anticipate and soften or...
The scientific revolution has revealed us, as individuals, to be incredibly tiny and ephemeral, and our entire existence, not just as individuals but even as a species, to be brief and insubstantial a...
The idea arose when Dan Rothman, a geochemist at MIT, was studying the graphs showing changes in the carbon cycle at the time of the Great Dying. He noticed something about the shape of the curves. He...
The Big Five extinctions are simply slightly more intense than the sixth- or seventh-largest declines, and you could just as easily discuss the Big Seven or Big Ten, depending on how you sliced up the...
One of the more extreme claims of the Gaia camp, at present neither proven nor refuted, is that the influence of life over the eons has helped Earth hold on to her life-giving water, while Venus and M...
Gazing over the countless fluctuations and transformations in Earth’s multibillion-year history, I am struck by the unique strangeness of the present moment. We suddenly find ourselves sort of running...
Cassie comes across as serious and studious, but once, after dinner in Washington with a group of NASA people, I asked her if her job title invited a lot of Men in Black questions. With little provoca...
The TTAPS study and the wider debate it ignited helped drive home the absurdity of nuclear strategies dependent on massive deterrence. The United States and the USSR had created a situation where even...
Now nearly circular, compared to other epochs, where it is slightly more egg-shaped—we inhabit an interglacial of exceptionally long duration. Models incorporating this fact suggest that, even without...
Climate scientist Ray Pierrehumbert, one of the coauthors on the recent National Research Council report on geoengineering by solar radiation management,9 put it, trying to do this anytime soon would...
Since, as I’ve indicated, we don’t fully understand the mechanism by which the orbital Milanković forcing causes large climate swings, there is a lot of uncertainty here. The last warm interglacial be...
Most of the evidence uncovered by Galileo would have been discovered by a similar fly-by spacecraft as long ago as about 2 billion years. In contrast, modulated radio transmissions could not have been...
Less than eighty years later, we know all these ideas about origins (of Earth, the planets, the Moon, and mountain ranges) to be completely wrong. We’re certainly not any smarter today than they were...
Here, I find it useful to point out the distinction between cleverness and wisdom. Cleverness is the ability to solve problems through invention and innovation. We’ve got that in spades. Wisdom is the...