http://www.dailygalaxy.com/my_weblog/201...zatio.html
EXCERPT: In a cogent answer to physicist Enrico Fermi's famous paradox --if intelligent life exists in the Milky Way, where are they? Life on other planets would likely be brief and become extinct very quickly, say astrobiologists from The Australian National University (ANU). In research aiming to understand how life might develop, the scientists realized new life would commonly die out due to runaway heating or cooling on their fledgling planets. A plausible solution to Fermi's paradox, say the ANU researchers, is near universal early extinction, which they have named the Gaian Bottleneck....
EXCERPT: In a cogent answer to physicist Enrico Fermi's famous paradox --if intelligent life exists in the Milky Way, where are they? Life on other planets would likely be brief and become extinct very quickly, say astrobiologists from The Australian National University (ANU). In research aiming to understand how life might develop, the scientists realized new life would commonly die out due to runaway heating or cooling on their fledgling planets. A plausible solution to Fermi's paradox, say the ANU researchers, is near universal early extinction, which they have named the Gaian Bottleneck....
Quote:The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens. Early life is fragile, so we believe it rarely evolves quickly enough to survive. Most early planetary environments are unstable. To produce a habitable planet, life forms need to regulate greenhouse gases such as water and carbon dioxide to keep surface temperatures stable.