Earth's Extremes Could Hold Clues to Mars Life

space.com ^ | 04/03/07 | Jeanna Bryner

[KevinDavis]

Results from a recent study of the microbes in China’s remote deserts could help astrobiologists refine their maps for uncovering Martian life.

Ongoing studies of Mars analogs on Earth have combed the iciest regions and the driest areas. But the new study, published in the Feb. 15 issue of the Journal of Geophysical Research-Biogeosciences, is the first comprehensive look at the microbial life in the extreme deserts of China.

“If you go to the Dry Valleys in Antarctica, that is arguably the coldest place on Earth, and certain areas in the Atacama Desert are some of the driest on Earth,” said lead author Kimberley Warren-Rhodes of NASA Ames Research Center.

[KevinDavis]

[SunkenCiv]

Didn't check, but this link is probably good and dead.

Earth's Oxygen Enigma
by Kathy A. Svitil
February 11, 2003
Carrine Blank of Washington University in St. Louis

Scientists have long believed that blue-green algae arose 3.5 billion years ago, pumping out oxygen and causing the oceans to fill with rust. Over the next billion years the algae transformed Earth's atmosphere, allowing oxygen-breathing life to evolve. Carrine Blank of Washington University in St. Louis... compared genetic sequences from 53 different groups of bacteria -- including blue-green algae, also known as cyanobacteria -- to construct a detailed family tree. The results confounded her expectations. "Cyanobacteria arose fairly late, about 2.2 or 2.3 billion years ago. That explains why we see this very sudden increase in oxygen, around 2.2 to 2 billion years ago, which has always been a big mystery," she says. The finding implies that something else caused the ocean rusting.