NAI
2001 Annual Science Report
University of Washington
Reporting | JUL 2000 – JUN 2001
Executive Summary
Executive Summary — UOW (dm)
The surge of interest in astrobiology has resulted in new information about many aspects of early evolution and the range of conditions under which life can exist, based largely on new understandings of extremophilic microbes. Far less understood, however, is the frequency and range of conditions under which more complex organisms, specifically metazoans, might occur and survive for long periods of time. Together, astrophysical and geophysical processes have provided the molecular components of life, the carbon and energy sources to sustain life, and the diverse and changing environments on earth that favor evolution and biocomplexity. In fact, increasing biocomplexity is one common trend of the evolution of life on Earth and is the result of a co-evolution of organisms with their environment. The interchange between the complex environmental factors and molecular mechanisms that led to the evolution of eukaryotes and metazoans from a common microbial ancestor are not known. However, recent advances in isotopic and organic analyses of rocks, molecular techniques, and astrophysical models have made it possible to begin the task of understanding how life emerged and evolved biocomplexity and what life forms could be expected to exist on other planets that have evolved through geological stages that overlap conditions on Earth during the past 4 Ga.
Our over-reaching assumption is that Earth life is representative of life elsewhere in that it will be carbon based, require liquid water, and use energy sources that are associated with universal astro- and geophysical processes. Our research program is focused on planetary habitability and the evolution of biological complexity. This is integrated multidisciplinary effort with concentration on four broad problems:
1. How often do planets with truly Earth-like properties form?
2. How important is plate tectonics in the formation and maintenance of metazoan life?
3. How important are mass extinctions for the evolution and extinction of complex life: are mass extinctions fertilizer or poison (or both) in the garden of complex organisms?
4. What are the evolutionary pathways by which complex organisms originate from microbes?