WOW, a 'live' missing link has been found.

Great Lakes sinkholes a window to ancient life

Bacteria at bottom of Lake Huron's Thunder Bay recalls period of 300 million years ago

Researchers found that the purple bacteria can photosynthesize as easily in sulfur-rich water as they can in freshwater, an ability suited to the dim and sulfur-rich conditions of shallow, primeval seas that existed billions of years ago.

"We see this as a peek into the ancient world," said research ecologist Bopaiah Biddanda of Grand Valley State University in Michigan. "This sort of life was not supposed to be occurring in the Great Lakes."

The bacteria also could eat sulfur, a primitive metabolic ability mostly abandoned when bacteria figured out how to use oxygen for photosynthesis billions of years ago.

Last spring, gene sequencing produced a startling result, said University of Wisconsin-Stout biologist Stephen Nold. When the DNA sequence was fed into a computer to compare with other species, the closest match was Phormidium autumnale, a rare bacterium found on an Antarctic lake floor.

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