Microbes are essential for the health and functioning of the environment, yet their diversity, in terms of the number of different kinds and their functions in the environment, remains largely unexplored. In very dry desert, when water is scarce and solar radiation high, the inside of rocks provides the last refuge for microbial life. Using an array of laboratory experiments and field measurements, this research will characterize the diversity and activities of microbial communities found inside rocks in deserts around the world. This project will inform us on the diversity of robust microbes that we might expect to find when desertification takes place and help determine the recovery potential of an area after long periods of desertification. By increasing our knowledge of the diversity, evolution, and ecology of desert microbes, we will learn more about our biosphere and how to better conserve resources and protect the environment.

Using a large-scale interdisciplinary approach, this project will identify the factors that govern the genetic, structural, and functional composition of endolithic (living in rock) microbial communities from arid environments. This research will provide a survey of the biodiversity of microorganisms inhabiting endolithic ecosystems using high-throughput gene sequencing and state-of-the-art microscopy methods. In addition, the researchers will determine the genetic diversity and molecular adaptations of photosynthesizing organisms from these ecosystems using culturing and single-cell genomics. Results from this study will provide a comprehensive survey of the biodiversity of microorganisms inhabiting endolithic ecosystems from several continents, determine whether the local environment, (i.e. rock type and local climate) or the global environment (i.e. biogeography) strongly impact community composition, and identify molecular adaptations of phototrophs from these ecosystems and how they relate to environmental variables. One postdoctoral fellow, a graduate student, and several undergraduate students will participate in this project. A public high school in Baltimore City will be involved in activities centered around the geology and biology of arid deserts around the world and the impact of desertification on human well-being. One high school student will participate in a field expedition in the US. The general public will be engaged via an international citizen science project.

National Science Foundation (NSF)
Division of Environmental Biology (DEB)
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Katharina Dittmar
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Johns Hopkins University
United States
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