Could you tell me about the path you took to becoming a scientist?
I did my undergraduate work in California. I actually began as a studio art major, but I started taking a biology class my junior year, and that class really sparked my excitement. I had had a lifelong interest in streams and water, and I started studying quite a bit of that. I ended up getting my undergraduate degree in biology with an emphasis on aquatic systems. I then did my Ph.D. at U.C. Davis on lymnology, the chemistry of lakes, streams and rivers. I worked a lot at Lake Tahoe, which is a wonderful lake because it almost functions like an ocean. What was so fascinating about my graduate experience was that the study of lakes is a very interdisciplinary field, in that it has biologists, chemists and physical oceanographers. For me, this opened my eyes to what interdisciplinary work really is. Even more than that, [my work] had a very strong applied component. Everybody at Lake Tahoe did a lot of basic research, but we were all deeply aware of the kind of work we did and its implications—how it affected air quality in the basin, transportation, and fisheries management. It really took me to that next level,. I was studying patchiness, aggregation and how they actually might be viewed [in the context of] fishery management, resources, air quality, and water quality.
What do you think is the most exciting thing happening in your field right now?
I think people are very aware that clean water is a vanishing resource. Clean water is an essential resource, and it is one that is not equally distributed. People have begun to recognize this, and [researchers in my field] have moved away from studying a single lake, a single river basin, and a single population. Instead, they are really much more interested in understanding global trends. How can environmental changes in air across the globe influence the water systems throughout the world? This is just one of the many big patterns of climate change that affect all the temperate zones. In addition, some introduced species not only move from one lake to another, but also go from continent to continent, which can drastically alter the dynamics of the food web. Mercury is a really good example [of climate change patterns]. Once it gets into the air from an incinerator, it then travels across the globe. So if you’re interested in the influence of mercury on resources on human health, you need to expand your study worldwide. You need to develop collaborations across countries. You need to have large global teams and large databases of information. You need to look at a lot of different systems. All of these things that scientists need are scaling up in very exciting ways.
A lot of your research concerns mercury levels. What are your thoughts on the rising levels of water pollution? Do you think there are any viable solutions?
There are a lot of different types of pollution, and you need to have different strategies for things that come in from different pathways. People are realizing the importance of finding the pathway from which pollutants come. For something like mercury, there is a fairly easy set of solutions, and that is to scrub mercury from the source. It would take years for it to no longer be in the system, but we could stop that, just like we could stop acid rain. There are [simple] solutions like that [to pollution]. When you look at nitrogen pollution and pollution related to logging—another source of pollution that might really influence the water quality in a lake or a set of streams—there is a whole other set of remediations. So, I think what we are seeing is that, problem-by-problem, you can find a number of solutions. We do not have a nationwide strategy that tries to look at them together. We are very good at reacting and coming up with solutions, but not at putting in place what is necessary to reduce that problem. The next step is really getting more anticipatory about it and getting people to think we found this solution to this problem. That, I think, is a very important issue.
Do you think it is mostly a policy problem?
I think policy is a big part of it. I do not think policy is the only part of it, though. We do not know everything. Some things are new. There are certain kinds of chemicals for which there’s not a natural analog. One of the biggest examples is the number of nanoparticles that are now created. People do not really know what those nanoparticles are. They come in all chemical forms: some are inert, and some are highly reactive. They are entering a lot of environmental systems. So, there is a lot of science we do not know as new things arise. Still, there’s also a lot about the policy about putting the solution in place that needs to improve. How do we distribute [clean up] costs? Where did they come from? Those are policy issues. We don’t have a good way for people to understand environmental costs because they tend to be long term.
What do you think of the world water crisis?
The water crisis is a result of the growing population. Populations need access to clean water. But, in addition, we have a lot of practices about land use that exacerbate the problem and make the water we do have of low quality: the way we develop water sheds, the loss of tress, the changes in the way we regulate pollutants going into the water systems, and the increase in pollutants going into estuaries. We have a lot of problems that decrease the amount of water of good quality. There is a lot of pressure on water resources.
I think we need agreements across countries. Who regulates the oceans? What anybody does in that ocean is a common resource. Who is responsible for the common resources? How do you draw from the commons? That has to be part of the solution.
Clearly, we need to find a better way to protect the water resources we do have. We have some technological fixes from irrigation to replenishing the land. There is a lot of exciting stuff that is happening in agriculture, including the ways you can construct landscapes so that they are better at conserving water. There are a lot of developing technologies that can help with this problem, but until we can get groups that can work across common boundaries on our resources, we will not really be able to solve that problem.
You recently published a paper in which you were able to lower the relative concentrations of mercury per biomass in a population of Daphnia pulex (water flea) by feeding them higher quality algae. What are some of the implications of this research?
The interesting thing about mercury is that it is a biomagnifier. Mercury increases in concentration the higher up an organism is on the food chain. But people have also noticed that you tend to have higher concentration in lakes and systems that appear pristine—cleaner. We have been doing a lot of work that explains the transfer from who eats what. It’s a food web primary mechanism. The longer the food chain, the more biomagnification you get. Also, the simpler the food chain, the more biomagnification you get. Something new we have noticed is that, when you have lots of biomass—such as in a green-looking lake—with the same food chain length as, say, a clear looking lake, you would get more mercury accumulating in that clearer lake. The more biomass there is, the more diluted the per-bite transfer of mercury is. It has a lot to do with how much food that animal needs to meet its own metabolic needs. If food has greater nutritional value, animals would be able to eat less. Our research helps explain some of the global patterns in mercury we see, which might be higher in fish from certain systems than from other systems. Our goal is to try to understand those connections so people can obtain reliable information on where and how to consume fish, as well as a better direction on how to manage the water system.
Do you see some potential applications for this research? Say increasing the biomass at the bottom of food chains to thin out pollutants?
People are saying a lot about that. It might be really important when you talk about fish farming. When you farm fish, you have a lot of influence over the quality of the food they eat, their biomass, and the rate at which they grow. In highly managed systems, there are a lot of applications. The research is a lot more exploratory when it comes to larger systems that we cannot really control. It would be very hard to control this in Lake Erie. Open ocean fish farming could have some very interesting applications for this research, though.
Changing gears now, let’s talk about women in science. How have you seen the role of women in science change since you first entered academia, and where do you think that role is headed?
Well, I feel very lucky. I’ve been in science through a lot of that change. When I first came to Dartmouth and started as a faculty member, there was only one other woman in the department. The number of female science majors was low. Now, we’re at least 50%. The faculty is not yet 50:50, but it is certainly getting closer to that. I have seen major changes, which have been accompanied by changes in basic education, and in the way women have started to see their capacity in the work force really grow. I think that’s really exciting. I think Dartmouth’s Women in Science Program is a real pioneer, and I felt so lucky to be on the ground floor of that.
However, there still are hurdles, especially with partners. When you have a couple that wants to get a job, there is a lot of difficulty in that, and traditionally it has not been the woman who gets her first choice. Having a family, which typically comes at the beginning of a career, can be particularly difficult for the woman if she also has primary child-care responsibilities. We do not have workforce policies that have really reinforced bringing women into science, although it has been progressing. I think we are really moving in the right direction and bringing women into science has been really healthy for science.
Where do you see Dartmouth in 30 years. What do you think will have changed, and what do you think will have stayed the same?
Dartmouth is in an incredibly beautiful place. I imagine a kind of place like Dartmouth is going to become even more unusual in 50 years. I do not think there are going to be that many places where people can go and have an incredible high quality education that can be in such a beautiful setting, and with access to so many people. I believe we will have many more connections across the world. We will continue to have that face-to-face contact and access between the student and the faculty, which is at the heart of what is special about us. But I imagine we will also have at our fingertips access to much more than what is available in our current footprint.
Someday, I would love to hear what you think. In some ways we are trying to build a future for your generation and people that are being born now. Your group is coming in with very different expectations. They may still be attracted here because of the faculty access we have, but they are not going to want to sacrifice that global touch which is becoming increasingly essential to our world. We are going to become something like Central Park, a place where somebody decided a long time ago to really protect, but is still totally porous to the rest of the world.
Lastly, what advice do you have for aspiring scientists?
Stick with it. Right now [science] is a big area of national need. It is one area in which the United States has leadership. It clearly needs to keep some of its most talented students.
I would say to the aspiring scientist: take advantage of interdisciplinary study. Access to more than one discipline in this time of your life, when you have not yet had to specialize, is really exciting. You can develop that high-end specialist knowledge in the future, but take advantage of these other things that you can do now. It will never be easier to do than as an undergraduate.
The best scientists are going to be the ones that are the most fluid. The technology has changed, and the questions have changed. [Scientists] are going to have to be the people that can negotiate new advances, and speak across disciplines. The scientist that can maintain that kind of fluidity is going to become an extremely valuable resource in the future.