With Speed and Violence Fred Pearce - Global Commons Institute

ocean depths, where extensive acidification would have been almost certain.
"Right now, most everybody seems to accept that the release of methane
clathrates is the only plausible explanation for what happened 55 million
years ago," says Dickens.
His chronology goes like this. For several million years, the world was
warming, probably because of extraterrestrial influences such as the sun.
The warming gradually heated sediments on the seabed until the clathrates
started to shatter and release methane. Perhaps it happened in stages, with
warming releasing methane that caused further global warming that
released more methane. But at any rate, over a few centuries, or at most a
few thousand years, trillions of tons of methane were eventually released
into the atmosphere—enough to cause the observed global shift in carbon
isotopes and a large and long-lasting hike in temperatures.
"The world just went into chaos," as Dickens puts it. Life on Earth was
transformed almost as much as by the asteroid hit 10 million years before
that wiped out the dinosaurs. Once the methane releases had ended, the
planet's ecosystems gradually absorbed the remainder of the great fart, the
climate recovered its equilibrium, and the oceans settled down again. But
the evolutionary consequences of that long-ago event have lasted to this day.
By the time the climate had recovered, many land and ocean species had
become extinct, while others evolved and flourished.
"At the same time as the great warming, there was a major evolution and
dispersal of new kinds of mammals," says Chris Beard, a paleontologist at
the Carnegie Museum of Natural History, in Pittsburgh. It was "the dawn of
the age of mammals." Among those on the evolutionary move were all kinds
of ungulates—including the ancestors of horses, zebras, rhinos, camels, and