When a 6-mile-wide asteroid struck Earth at the end of the Cretaceous period some 66 million years ago, it wiped out the majority of living organisms. Many victims were instantly fried by fires or drowned in tsunamis. The rest, meanwhile, succumbed to hostile conditions and the gradual collapse of entire ecosystems. In the end, about three-quarters of all species were swept into oblivion.
Yet many also survived and, eventually, repopulated the planet. Every living thing today is descended from the resourceful (or lucky) few who found ways to eke out an existence in that apocalyptic landscape. But how did those organisms persist long enough to see the world through to better days?
The challenge to life was immediate — within minutes of the impact, a global pulse of thermal radiation raised Earth’s surface to lethal temperatures. Marine species were safely insulated, but the survival of land-dwellers demands explanation.
In 2004, ...
