I am a faculty member in the Biology Department of the Woods Hole Oceanographic Institution. During the Extreme 2003 cruise, I will be studying how vent geochemical environments differ (and if they do) across the spectrum of hydrothermal habitats as well as looking at how vent fluid chemistry changes (and whether it does) over short time scales (days to weeks).

Working with Dr. Luther and Dr. Nuzzio, I will be implementing a newly developed electrochemical analyzer, an autonomous fluid chemical sampler, which will permit discrete measurements of the chemical nutrients surrounding a variety of hydrothermal animals over biological time-scales. In addition, tubeworms, mussels, and other animals living where chemistry is measured will be collected and assessed for their fitness and for future studies involving gene expression.

What kinds of questions will you try to answer, and why?

Hydrothermal vents provide ephemeral habitats for deep-sea fauna that rely on chemosynthesis for their livelihood. Biologists have long proposed that the chemical compositions of vent fluids serve as settlement cues for vent-dependent fauna to colonize vents as well as the major influence controlling the distribution and succession of vent community assemblages along mid-ocean ridges; however, these hypotheses remain largely untested. In addition, microbial community composition in vent fluids and the development of microbial biofilms at vent openings would be expected to vary in response to vent fluid chemistry, and may facilitate, inhibit, or somehow mediate the development of vent communities.

The major objective of my research during Extreme 2003 is to characterize the range and variability of geochemical conditions in habitats occupied by different vent invertebrate species in order to understand the influence biological/geochemical interactions during colonization, growth, and reproduction of different species at deep-sea hydrothermal vents. I will, through time-series studies, combine molecular genetic characterization (DNA sequences) of colonists and in situ measurements of fluid chemistry. Invertebrate species colonization in conjunction with co-located, in situ, time-series detection of dissolved H2, H2S, pH, and temperature at a hydrothermal vent on the East Pacific Rise will allow us to evaluate the chemical environment as a major factor controlling the structure of communities over time. I am pursuing the Extreme 2003 and future planned studies in order to capture fundamental insights into how hydrothermal fluid chemistry, microbial biofilms, and interactions among different species structure chemosynthetic communities, and the ultimate development of megafaunal assemblages in disjunct and emphemeral vent sites.

Hydrothermal vents on mid-ocean ridges represent model systems wherein invertebrate, vertebrate, and microbial populations persist in ephemeral, naturally fragmented habitats. Persistence of a species in ephemeral and fragmented habitats requires that populations grow, reproduce, and disperse to new sites. The overall significance of this research lies in the characterization of the physical and biological parameters and mechanisms by which chemosynthesis thrives under these conditions in the deep sea. Vent fluid chemistry is intimately controlled by the spatial and temporal variability of water-rock interactions, and those reactions subsequently determine the available nutrients for chemosynthetic microbes and robust faunal assemblages. Understanding the dynamics of fragmented vent ecosystems is critical as human activities destroy and degrade coastal habitats in ways that produce fragmentation and isolation. If we can understand how vent organisms persist, we may gain insight into management practices that would allow coastal organisms to persist in the face of increasing habitat fragmentation.

What is your educational background? What lured you into marine research?

I have a bachelor’s degree in biology and German from the University of North Carolina (UNC) at Chapel Hill, and a doctorate in ecology and evolution from Rutgers University. Growing up on the North Carolina coast, I developed a fascination with marine life, but it wasn’t until my days at Carolina that my path was set. As a sophomore, I told my marine sciences professor, Dr. Conrad Neumann, that I wanted to be a marine biologist. Neumann advised me to look beyond simply studying oceanic life and recommended that I study genetics or chemistry, which could be applied to marine science. I paid heed to the suggestion and after graduation went to work in the molecular genetics lab at the Environmental Protection Agency (EPA) in Research Triangle Park, North Carolina, and continued to take marine classes at UNC. If it weren’t for those three years gaining molecular genetic experience, I would not have the skills I need to address rapidly evolving ecological and evolutionary questions in deep-sea chemosynthetic ecosystems.