Introductory Seminars for First-Year Students

Life at the Extremes: From the Deep Sea to Deep Space

EARTHSYS 36N

Life has existed on Earth for about four billion years, and colonized nearly every inch of its surface. Is life likely to survive elsewhere in our solar system? Or in our universe? In this seminar, we will study extreme microbial life—specifically bacteria and archaea—on Earth, and consider the potential for life in extraterrestrial locales. We will focus on the microbes of the deep sea, living in toxic and nearly boiling waters at hydrothermal vents, eating methane at cold methane seeps, surviving pressures up to 400 times that on the surface of the earth, and often supporting bizarre animal life through complex symbioses. You will learn about the adaptations these microbes have developed to survive and thrive in these harsh environments and the tools scientists use to study them, including submarines and remotely operated submersibles. We will discuss the definition of life, what its limits may be, and the possibilities that Earth-based life might colonizie extraterrestrial bodies and that life might have evolved elsewhere independently. Our class will be interactive, including discussions, hands-on microbiology lab experiences, and local field trips. Our readings will include articles from popular media and reports from the scientific literature. At the end of this seminar, you will understand the diversity and resilience of microbial life, the important ecological role microbes play on Earth, and how to speculate scientifically about extraterrestrial life.

Meet the Instructor(s)

Anne Dekas

Anne Dekas is a faculty member in the Department of Earth System Science. Her research focuses on the diversity and activity of microorganisms in the deep sea, and how their metabolisms affect global-scale cycling of greenhouse gases. She has worked with several manned and remotely operated submersibles to collect samples, including DSV Alvin, the submersible made famous for its work investigating the Titanic, among other expeditions. Professor Dekas received her B.A. in earth and planetary sciences from Harvard University, and her Ph.D. in geological and planetary sciences from the California Institute of Technology. She was a Lawrence Postdoctoral Fellow in the Chemical Science Division at Lawrence Livermore National Laboratory. Professor Dekas has long been interested in space sciences, and has performed research at three NASA centers: Goddard Space Flight center, Ames Research Center, and the Jet Propulsion Laboratory. She is passionate about exploration, in both the deep sea and extraterrestrial bodies, and sharing her knowledge and enthusiasm with the next generation of explorers.