Friday, September 23, 2005

Beauty and terror

Almost every week lately the journals Science and Nature warn about the threat of a worldwide pandemic of avian flu originating in southeast Asia. It's even the cover story of this month's National Geographic.

Flu is caused by a virus, a snip of renegade RNA or DNA in a protein shell. Viruses can only reproduce by hijacking the chemical apparatus of invaded cells. Yours. Mine. The 1918 influenza pandemic claimed 20 to 40 million lives worldwide.

And yet, and yet . . .

They are beautiful.

Computer-generated images of viruses, as revealed by X-rays and the electron microscope, rival in their loveliness the rose window of Chartres. The beauty of a virus is a matter of necessity. A virus has only enough genes to code for a few proteins. To build its shell, it must use the same few proteins over and over, like the repetitive pattern of patches on a soccer ball. For many viruses, the result is an icosahedral structure, with 20 identical triangular faces, one of the five regular polyhedrons admired by the Greeks as the epitome of beauty.

"Euclid alone has looked on beauty bare," wrote Edna St. Vincent Millay. Euclid was a geometrician. The beauty of a virus is geometrical. Making do with life's bare minimum, a virus comes up with beauty bare.