A Really Short History of Nearly Everything. Bill Bryson by Bill Bryson

Author:Bill Bryson [Bryson, Bill]
Language: eng
Format: epub
Tags: Science & Nature, Discoveries, General, Juvenile Nonfiction, History of Science
ISBN: 9780552562966
Publisher: Molino
Published: 2008-12-14T23:00:00+00:00

microparticles of dust and sand, which became bound together to form slightly weird but solid structures—the stromatolites that were featured in the shallows of the poster on Victoria Bennett’s office wall. Stromatolites came in various shapes and sizes. Sometimes they looked like enormous cauliflowers, sometimes like fluffy mattresses ( stromatolite comes from the Greek for “mattress”), sometimes they came in the form of columns, rising tens of meters

above the surface of the water—sometimes as high as a hundred meters. In all their

manifestations, they were a kind of living rock, and they represented the world’s first

cooperative venture, with some varieties of primitive organism living just at the surface and others living just underneath, each taking advantage of conditions created by the other. The world had its first ecosystem.

For many years, scientists knew about stromatolites from fossil formations, but in 1961

they got a real surprise with the discovery of a community of living stromatolites at Shark Bay on the remote northwest coast of Australia. This was most unexpected—so unexpected,

in fact, that it was some years before scientists realized quite what they had found. Today, however, Shark Bay is a tourist attraction—or at least as much of a tourist attraction as a place hundreds of miles from anywhere much and dozens of miles from anywhere at all can ever be.

Boardwalks have been built out into the bay so that visitors can stroll over the water to get a good look at the stromatolites, quietly respiring just beneath the surface. They are lusterless and gray and look, as I recorded in an earlier book, like very large cow-pats. But it is a curiously giddying moment to find yourself staring at living remnants of Earth as it was 3.5

billion years ago. As Richard Fortey has put it: “This is truly time traveling, and if the world were attuned to its real wonders this sight would be as well-known as the pyramids of Giza.”

Although you’d never guess it, these dull rocks swarm with life, with an estimated (well, obviously estimated) three billion individual organisms on every square yard of rock.

Sometimes when you look carefully you can see tiny strings of bubbles rising to the surface as they give up their oxygen. In two billion years such tiny exertions raised the level of oxygen in Earth’s atmosphere to 20 percent, preparing the way for the next, more complex chapter in life’s history.

It has been suggested that the cyanobacteria at Shark Bay are perhaps the slowest-evolving organisms on Earth, and certainly now they are among the rarest. Having prepared the way for more complex life forms, they were then grazed out of existence nearly everywhere by the

very organisms whose existence they had made possible. (They exist at Shark Bay because

the waters are too saline for the creatures that would normally feast on them.)

One reason life took so long to grow complex was that the world had to wait until the simpler organisms had oxygenated the atmosphere sufficiently. “Animals could not summon

up the energy to work,” as Fortey has put it.

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