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That's quite a statement in the world of biology. . |
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See, biologists traditionally like to think the appliances of life can't all fit into a
package much smaller than a normal bacterium, which is about one micron, or one-millionth of a
meter, in diameter. But Folk's nannobacteria are one-tenth that size or less. Even viruses,
which can be smaller still, don't qualify for full "life" membership, most
microbiologists
agree, because they don't make their own food, or "metabolize," and their reproduction
depends entirely on a host cell's appliances.
So how does a rock jock come to shake up biology with an earth-shattering new life form? "Dumb luck," says Folk. "That's spelled, D-U-M ... ." That, and a new electron microscope. Electron microscopes use a stream of electrons to deliver tremendous magnification, and Folk's latest was capable of magnifying things 100,000-fold. Folk was examining a mineral sample taken from an Italian hot spring in 1990 when he noticed decidedly un-rocklike shapes inside the rock: They looked like spheres, jelly beans and worms -- and they made normal bacteria look like towering giants. |
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And now that he's looking for them, he sees them everywhere: on rotting leaves, on rusting iron and greening copper, in sheets of sedimentary clay. . |
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He sees so many nannobacteria that he is willing to suggest that if you put all the world's
nannobacteria on one side of a scale, and all other life forms on the other, nannobacteria
would rule.
But Folk has no desire to be mistaken for a microbiologist, let alone a nannobacteriologist, and dearly wishes a genuine one would quit fooling around with ordinary bacteria and investigate "my little guys." He theorizes that the nannobacteria may have a negatively charged cell wall that attracts positively charged bits of calcium, aluminum and other minerals. These would "calcify" on the nannobacteria, essentially fossilizing them. Put a few jillion-gazillion fossilized nannobacteria together and you get a rock. Or a clam shell. Or a skim of rust. Proving all this will take some doing. Extracting genetic material from nannobacteria would help to prove they're not bits of dust or other contamination. But Folk says Finnish microbiologists have extracted DNA from nannobacteria found in horse and human blood, and that biology journals won't publish the findings. And even possessing DNA, as viruses can testify, is no guarantee of acceptance as a life member. It must be tempting to just clap loudly and see if the blobs startle, but their size presents a problem. |
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They could be doing the Macarena, for all Folk knows, but they're too small to be spied upon with a conventional microscope, and the electron microscope fries them instantly, leaving only their fizzled corpses. . |
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Folk's belief that his critters are alive got a boost when NASA microbiologists who had heard
of Folk's little guys pointed an electron microscope at a hunk of Martian meteorite, and,
ta-da, found fossils of life-shaped objects (including one fondly nicknamed "the
Cheet-oh"). Even better, chemists
investigating the Mars rock identified traces of gases typically released by living things.
But conclusive evidence, Folk's lively coffee-slime notwithstanding, is still missing, and
the possibility that life on Earth is underwritten by nannobacteria remains a tantalizing
theory. Maybe they should call the elusive blobs "Nah-nah bacteria."
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 Vocabulary
Why Asparagus Makes Your Pee Stink
Why We Can't Tell What Time It Is
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Hannah Holmes thinks twice about what's in her coffee over breakfast in Portland, Maine.
Her numerous contributions to Discovery Online include "Hitchhikers' Guide to the Hubble". She also writes
for Escape, Outside, Sierra,
Backpacker, Eco Traveler and Women's Sports and Fitness. Write her at skinny@online.discovery.com.
Main Illustration: Brian Frick | Copyright © 1997 Discovery Communications, Inc. |