Research in the McDermott lab investigates the biogeochemistry of deep seawater, seafloor hot springs, and ancient terrestrial fracture waters that are tapped by deep mines that are drilled into some of the oldest rocks on Earth. As aqueous chemists, McDermott and her students seek to understand the sources and fate of dissolved species and gases of all types that are found in natural waters. Depending on the question at hand, work in the lab spans the periodic table. Research ranges from the determination of the carbon- and sulfur-rich building blocks of life, to the dissolved gases that drive ecosystems, and the trace metals that catalyze reactions that occur at the cellular level. Research performed by McDermott and her students addresses the key questions of (1) What conditions support microbial communities in subsurface biosphere, hydrothermal vent ecosystems and in deep, saline, isolated fracture waters? (2) Are organic species in these environments produced in the absence of life, or are they generated by processes linked to life? (3) How can chemical cycling in these environments illuminate possibilities for the synthesis of organic compounds around 4 billion years ago, before life began on early Earth?
McDermott is also pursuing new lines of research in understanding how varying conditions, such as temperature, pH (relative acidity), and redox state (the relative balance of oxidized species that contain oxygen versus reduced species that contain hydrogen), affect the stability of environmental (e)DNA in the deep water in the Gulf of Mexico. In these waters, efficient new methods of estimating biodiversity are needed to define the boundaries of marine sanctuaries, which are under threat by offshore oil extraction efforts. All organisms continuously shed cells and leak DNA into their surrounding environment. This eDNA can now be readily detected in natural water samples and analysed to identify nearby organisms. As such, eDNA is a new methodology that could be used to rapidly explore and characterize local marine biodiversity. The McDermott lab is working to apply these techniques to the Gulf of Mexico, to answer the questions: (4) What chemical or physical conditions control the persistence of eDNA in deep marine waters? (5) For how far, and how long, does eDNA persist in the water column, and how can it be best applied as a quantitative tool to assess the biodiversity of nearby ecosystems?
The driving principles that McDermott seeks to instill through teaching are centered on inquiry-based exploration that is grounded in the discussion of classic theories, new debates and what knowledge remains unknown. She employs strategies underlying authentic research to build knowledge, rather than rote memorization, and formulates questions as logical problems. McDermott teaches undergraduate and graduate level classes that range in complexity from introductory to advanced topics. Her education and research experience integrates Earth science, geochemistry, oceanography, and marine and terrestrial groundwater chemistry.
McDermott teaches a first year seminar entitled ‘Life from Stardust: the Origin of Earth and the Biosphere’ (EES 090). This discussion-based class integrates group activities, lab demonstrations and experiential learning. The course focuses on how the history of the Earth intermingles with and shapes the development of life. Students define life and habilitabilty for themselves, discuss the nature of modern extremophile organisms, and are introduced to the techniques used for the search for life on other planetary bodies, both in our solar system and around other stars. McDermott also teaches an 'Earth History' course for undergraduate majors (EES 200). This course provides a thorough review of the coevolution of Earth, life, climate, and the environment, and an introduction to the records used to constrain this history. In this writing-intensive course, students develop writing skills beginning with sentence and paragraph structure and style of presenting analytical arguments based on logic, up through the development of more complex writing skills that focus on making persuasive, effective scientific arguments, the accurate and concise representation of research, and writing testable hypothesis in deductive science. McDermott also teaches a graduate level course in 'Chemical and Geological Oceanography' (EES 477). This course focuses on the pathways that chemical species follow on their transit through the world’s oceans, and the related geologic, chemical, and sedimentological processes that occur at the seafloor. A survey of modern and classic marine research is combined with quantitative approaches, with the goal to construct box models and calculate chemical fluxes across interfaces. Chemistry and geology are combined to understand the long- and short-term cycles of carbon, oxygen, nitrogen, and sulfur in the marine system.
Current graduate students: Susan Ambrose, William Dowd
Current undergraduate students: Tiffany Baumann, Talia Rodkey
Undergraduate student alumni: Grant Loescher (Lehigh BS 2018, now an MS student at Arizona State University)