Your work is currently focused on the microbes on and under the deep ocean floor. In a nutshell, what are these microbes doing?
If we knew, I would probably look for something else to do. The deep biosphere is a huge enigma. There was a paper published in 1998 by Whitaker that produced a census of what he thought the prokaryotic biomass in the world was – in the continental systems, in the marine realm, and so on. The controversial finding was that up to one third of Earth’s biomass carbon might be buried in marine sediments, which sent the community into a tizzy. Understanding who is there and what they’re doing—fundamental microbial ecology kind of questions—is what we’re after, but the complexities of studying them below the ocean floor requires very unique approaches and some long-term planning, which I am engaged in.
Where are your study sites? What’s your favorite?
We have a number of different study sites—my own baby is a site in the middle of the Atlantic where we’re setting up some ten-year observatories to study time series observations and experiments on microbial ecosystems below the bottom of the ocean.
What’s your sampling gear look like? Do you use an Alvin-type vehicle?
We actually use a very special drill ship that’s operated by the Integrated Ocean Drilling Program. You drill a hole, and then put an instrument down into the hole. We’ll recover the core, but then we’ll also deploy experiments and take measurements. When those observatories are set up, we’ll go back with ships that use something like the Alvin or the ROV Jason and service those observatories, collect samples, download data—those kinds of things. It’s very akin to setting up NASA-style missions to outer space. We call this our “inner-space” mission.
In a 2008 paper, you and your colleagues looked at the population structure of the microbial communities that live on basalt lavas. What did you find?
We found that the population structure of basalt was incredibly rich—very species rich. It was kind of a surprise to find out that the diversity of the basalts is something akin to that of soils. So now we think of the seafloor basalts as the “soils of the sea” in terms of species diversity.
Why do you think there is such a complex community on seafloor basalts?
I think that the microbial diversity reflects the chemical diversity of the different types of reactions that can occur on basalt. We think of basalt as this boring old rock on the sea floor. However, it’s really quite chemically complex in terms of its elemental composition. There is a rich suite of chemical reactions that can occur with sea water, with hydrothermal fluid, and, once you have a three dimensional biofilm community, within that biofilm.
You’re the director of the Center for Dark Energy Biosphere Investigations, which sounds kind of like a science fiction writer’s club. What is this organization?
This is a research coordination network. This is this group that we’re trying to get together to systematically study the deep biosphere. The research coordination network side of things is engaged in trying to build and educate this community of researchers to try and coordinate our science.
What is your lab working on now?
A lot of our focus right now is on developing new experimental systems to go into these observatories. It requires new technologies, working with engineers, and figuring out the best way to study microbiology in the deep subsurface biosphere.
If you had to change careers today and you could do anything, what would you do?
I’ve always wanted to operate a bagel shop. My husband and I have this fantasy, that if we didn’t get tenure, we would open a bagel-slash-pizza shop, where I would make bagels in the morning and then he would take over in the afternoon and make pizza. That was our bailout plan.
What’s your favorite science book?
I loved The Elegant Universe by Brian Green.
What is something about you that most people don’t know?
I don’t really like getting in the water, except in the bathtub.
Does that get in the way of your work?
No, I never have to get in, except in a submarine, which is just fine.