Monday, June 21, 2010

Are We Entering an Era of Self-Directed Evolution?

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In the past decade, we’ve examined our Solar System’s orbit through the Milky Way to ask whether there may be clues to periodic mass extinctions on our planet.

We've launched missions seeking out habitable Alien Earths and the existence of dark energy and have migrated from wondering if there's life on Mars to searching out and studying myriads of exo planets in the Milky Way and infinite galaxies beyond.

Our incredible advances have also underscored own, very human limitations — our eyes, notes astronomer James Kaler in his new book, Heaven’s Touch: From Killer Stars to the Seeds of Life, How We Are Connected to the Universe, see wavelengths between 0.00004 and 0.00008 of a centimeter.

Kaler calls our visual spectrum “…but one octave on an imaginary electromagnetic piano with a keyboard hundreds of kilometers long.”

Physicist Stephen Hawking believes that we have entered a new phase of evolution. "At first, evolution proceeded by natural selection, from random mutations. This Darwinian phase, lasted about three and a half billion years, and produced us, beings who developed language, to exchange information."

But what distinguishes us from our cave man ancestors is the knowledge that we have accumulated over the last ten thousand years, and particularly, Hawking points out, over the last three hundred.

"I think it is legitimate to take a broader view, and include externally transmitted information, as well as DNA, in the evolution of the human race," Hawking said.

In the last ten thousand years the human species has been in what Hawking calls, "an external transmission phase," where the internal record of information, handed down to succeeding generations in DNA, has not changed significantly. "But the external record, in books, and other long lasting forms of storage," Hawking says, "has grown enormously. Some people would use the term, evolution, only for the internally transmitted genetic material, and would object to it being applied to information handed down externally. But I think that is too narrow a view. We are more than just our genes."

The time scale for evolution, in the external transmission period, has collapsed to about 50 years, or less.

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