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Origin & Evolution of Life: June 2009


A central question of astrobiology concerns the origin and distribution of life in the Universe. For this reason, astrobiology can be considered to fall within the science called transitional biology. If we accept that life originated by a process of prebiotic chemical evolution, the next question concerns the nature of the transitional pathway from inanimate chemical systems to the first forms of life on Earth. These possible transitional states are the subject matter of transitional biology as a discipline.

With the assumption that future attempts to explore our Solar System for life will be limited by economic constraints, we have formulated a series of principles to guide future searches: (1) the discovery of life that has originated independently of our own would have greater significance than evidence for panspermia; (2) an unambiguous identification of living beings (or the fully preserved, intact remains of such beings) is more desirable than the discovery of markers or fossils that would inform us of the presence of life but not its composition; (3) we should initially seek carbon-based life that employs a set of monomers and polymers substantially different than our own, which would effectively balance the need for ease of detection with that of establishing a separate origin; (4) a "follow-the-carbon" strategy appears optimal for locating such alternative carbon-based life.

Timetree of Life

Scientists and non-scientists now have easy access to information about when living species and their ancestors originated, information that previously was difficult to find or inaccessible. Free access to the information is part of the new Timetree of Life initiative developed by NAI's Blair Hedges, professor of biology with the Penn State Astrobiology Research Center, and Sudhir Kumar, a professor of life sciences at Arizona State University.

The Timetree of Life project debuted with the simultaneous release of a book titled The Timetree of Life (Oxford University Press), which is written by a consortium of 105 experts on specific groups of organisms and is edited by Hedges and Kumar.

"The TimeTree of Life web tool belongs to a new genre of resources that lets anyone easily mine knowledge previously locked up in technical research articles, without needing to know the jargon of the field," said Kumar. "For example, if you type in 'cat' and 'dog,'" Hedges said, "the program will navigate through the timetree of life to the point where the cat and dog species split, and it will find all the studies bearing on that divergence. Within a few seconds, you will learn that your pet cat and dog diverged in evolutionary time about 50 to 60 million years ago." For more information: http://www.timetree.org/

[Source: NAI Newsletter]

by Pier-Luigi Luisi

The 2009 San Sebastian meeting on OQOL was the follow-up to an analogous meeting held in Erice, Sicily three years ago. The general idea was to identify and discuss the areas in the field that are still "in the darkness", i.e. remain poorly understood despite their importance. We asked what were the reasons of our persisting ignorance, and what could we do to shed light on the "dark" areas. The meeting was not organized as a series of standard lectures (the usual "talk-and-run-away" format). Instead, it was centered on several selected questions, one per half-day, which were first discussed by a panel of experts and then by all participants. The questions had been previously chosen through worldwide polling of researchers in the field. It was a very intense meeting - in four days we covered eight questions.

By Michael Wilson

The NAI held a strategic science initiative workshop in Tempe, AZ on May 13-15, to identify areas where increased collaboration between the funded NAI teams could lead to greater scientific insights and productivity. One of the initiative areas focused on origins of life research; the origins initiative was chaired by George Cody (Carnegie team) and John Peters (Montana State team) and Stephen Freeland (University of Hawaii team).By Michael Wilson

The NAI held a strategic science initiative workshop in Tempe, AZ on May 13-15, to identify areas where increased collaboration between the funded NAI teams could lead to greater scientific insights and productivity. One of the initiative areas focused on origins of life research; the origins initiative was chaired by George Cody (Carnegie team) and John Peters (Montana State team) and Stephen Freeland (University of Hawaii team).