The combined biomass of all domesticated animals is now some twenty-five times that of all remaining wild terrestrial mammals. Some of our favored plants have become among the most widely propagated o...
His suggestion is that we should adopt best practices so we don’t turn on our radar systems when they are pointed toward nearby stars, or intersecting the plane of the Milky Way galaxy, where there ar...
A few times, all the world’s land surface has clumped together into one giant supercontinent, surrounded by one global ocean. Even supercontinents drift, and 450 million years ago the planet was put o...
Work, Jacob was not claiming to make a detailed and correct prediction of climate changes over the next several hundred thousand years, only to determine whether our influence could be strong enough t...
Must choose a geological deposit to mark our time, one that is uniquely human-born, I would suggest the area of Mare Tranquilitatis, the Sea of Tranquility, on the Moon, where the Apollo 11 astronauts...
Titan, by our standards, is really cold, at -290 degrees Fahrenheit. Without any methane greenhouse, it would be much colder still, by about 22 degrees. Yet, if we put all that methane into a basic cl...
This afforded an opportunity for a close encounter with Earth as it might appear to an alien spacecraft, and Carl Sagan proposed using this as a control experiment for the search for extraterrestrial...
These disturbances are the product of our human propensity to explore in teams, to develop new tools to expand our domain to places that are not part of our natural habitat.
The exact kill mechanisms are still being worked out, but the chronology has now convincingly implicated the volcanic culprit. At just the precise geological moment when most species suddenly dropped...
The Anthropocene represents a braiding together of these into one inseparable narrative. This is the end of history, and of biology and geology—at least as separate stories. Have they become irreversi...
In 1929, as a young man, British biologist J. D. Bernal wrote a book entitled The World, The Flesh and the Devil that Arthur C. Clarke called, the most brilliant attempt at scientific prediction ever...
Also, Lovelock’s radical idea—pay attention to the atmosphere and look for drastic departures from the expected mixture of gases—now forms the cornerstone of our life-detection strategies.
Two stratigraphers asked, Is the Anthropocene an Issue of Stratigraphy or Pop Culture? In part, they argued that our presence is as yet too brief a perturbation to merit a named place in the stratigra...
Cities will be smarter, greener places. Over the centuries, we’ve made a lot of progress in learning how to urbanize. We invented plumbing and sanitation systems, learned not to stain our cities brown...
Celled. Then a catastrophe occurred (in the sense of sudden change), a dramatic increase in biodiversity, an anti-extinction, if you will. In a flash, there were not just some animal forms, but all of...
We’ve been lulled into an illusion of stasis by unusual climate stability during our short time here. If you include the rest of our history as a species (most of it), before we started keeping contin...
Titan’s upper atmosphere is a nonstop factory of complex organics, which both shroud this world in its permanent smoggy haze and snow down on the icy surface. There they gather in vast dune fields tha...
States Parties to the Treaty shall pursue studies of outer space, including the Moon and other celestial bodies, and conduct exploration of them so as to avoid their harmful contamination and also adv...
Now, traveling about twice as far back again in Earth time, back to 542 million years ago, we encounter another sudden massive wave of extinction instigated by runaway biology: The Cambrian substrate...
I began to see this as a series of dilemmas nested like Russian dolls. Can today’s SETI community agree on a policy about active SETI? Even if collectively forged and broadly ratified, would such an a...