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2003 Annual Science Report

Pennsylvania State University Reporting  |  JUL 2002 – JUN 2003

Evolution of Atmospheric O2, Climate, and Biosphere - K. Freeman

4 Institutions
3 Teams
0 Publications
0 Field Sites
Field Sites

Project Progress

Excellent progress was made on the study of Late Archean kerogens and biomarkers. (This work is largely funded by the National Science Foundation (NSF), with NAI support for personnel.) The integration of a rich molecular and isotopic data set is under way, with initial results documenting shallow-water facies as ancient “oxygen oases” (see highlights below). Additional work on molecular and isotopic biomarker studies as “life signatures” for ancient microorganisms continues. We have established trimethyl and tetramethyl benzenes as markers for green sulfur bacteria (see below). In addition, the research team is using molecular analyses of ether-linked lipids from archea to study the distribution of Chrenarchaeota in fresh to hypersaline salinities. We are also progressing on growing a methanogen that consumes small amounts of methane. We are testing and expanding the growth conditions for this organism in order to understand ecological constraints on its ability and mechanism(s) for growth.

  • PROJECT INVESTIGATORS:
    Katherine Freeman Katherine Freeman
    Project Investigator
  • PROJECT MEMBERS:
    Jennifer Eigenbrode
    Doctoral Student

    Jim Moran
    Doctoral Student

    Nikolai Pedentchouk
    Doctoral Student

  • RELATED OBJECTIVES:
    Objective 4.1
    Earth's early biosphere

    Objective 4.2
    Foundations of complex life

    Objective 5.2
    Co-evolution of microbial communities

    Objective 6.1
    Environmental changes and the cycling of elements by the biota, communities, and ecosystems

    Objective 7.1
    Biosignatures to be sought in Solar System materials