Research Projects
Human impacts on the marine environment are growing, species are being lost, and ecosystems are being altered. I combine marine ecology, environmental science, and engineering to test fundamental ecological questions and develop novel ecosystem restoration tools.
ARMS to reefs: A new tool to restore coral reef biodiversity, fisheries yields, and human health in Madagascar (NSF-funded project)
Coral reef restoration is particularly necessary in Madagascar where reef fisheries have declined, causing widespread human malnourishment. I am leading a Belmont Forum and NSF-funded international team that is building large artificial reefs on the seafloor (1 hectare) and seeding them with biota from healthy coral reefs using ARMS and other small structures. The project plan follows on a decision made by local Indigenous fishers to expand reef habitat, and we are aiding their effort. Our team will experimentally test, at reef scale, whether building reefs and seeding them with ARMS produces healthy reef ecosystems, increases fisheries yields, and improves human health. If successful, we will produce a new way to rebuild coral reef ecosystems, will greatly enhance the equitable and sustainable use of marine resources, and will respond to a threat caused by global change, all with a tool that can be applied anywhere reefs are found. For more information about this project, please visit: https://armsrestore.com.
Coral Reef Arks: a cost-effective and high-return tool for restoration and conservation of coral reef resources on DoD submerged lands (DoD-funded project)
As coral reefs have declined worldwide, most restoration has focused on improving coral survival, ignoring the other biological components of the reef ecosystem. To address this missing component, colleagues and I have created artificial structures and reef-enhancement technologies to build reef ecosystems in their entirety. We are demonstrating this approach for the US Department of Defense by “seeding” ARMS on healthy reefs and moving them, along with corals, to artificial structures to jumpstart whole-community growth. Our artificial structures are submerged, floating geodesic scaffolds called Arks, which increase light and water exposure, potentially improving ecosystem health. We are studying community health on Arks relative to control sites. These structures represent a novel conservation approach and provide an entirely new way to study coral reef ecosystem assembly and acclimatization. The potential advantages of Arks include creating “seedbanks” of healthy coral reefs, bolstering larval connectivity, increasing carbon sequestration and fisheries production, reducing pressures on natural reefs, moving reefs long distances, and creating a novel platform for scientific discovery, especially as it relates to ecological succession. In my lab, we are particularly focused on metabolite and microbial diversity on the Arks vs. the control sites to test the hypothesis that specialized metabolites production reflects environmental conditions. For more information about this project, please visit: https://coralarks.org/projects_pr.php.
Uncovering fundamental drivers of metabolite diversification in nature
Small molecules, which include many secondary metabolites and natural products, play important roles in physiological processes across Life. We know surprisingly little about what most small molecules are and what they do, even in our own bodies. In my work, I have developed a method to gain large amounts of information from complex mixtures of small molecules, even when we don't know what the molecules are or what they do. Using untargeted metabolomics, molecular networking, and machine learning, I have developed a tool to identify chemical reactions occurring among molecules, the first step in determining their biological activity and understanding how they help organisms defend themselves, mount immune responses, or survive when their environment changes. I have found that the “tools” for building biomolecules vary down to the level of individuals living in different locations, consistent with the expectations of acclimatization. This finding suggests a mechanism by which some individuals buffer changing environmental conditions while others do not, as is commonly observed during coral bleaching. Increased understanding of small molecule functions is necessary to better understand the toolkit of biology, from the pathways species turn on in response to environmental change to those that can be used in novel treatments for human diseases.
Coral reefs produce a wide diversity of small molecules that are involved in primary and secondary metabolism. Each circle in the network in the upper right represents an individual molecule detected on the coral reefs in the lower right, their connections reflecting their chemical structural similarities.
Understanding how differences in offspring characteristics determine their environmental tolerance
Parents pass on more than just genes. In marine invertebrates and many other animals, parents give their offspring a diverse suite of molecules and microbes, all of which may (or may not) help these offspring wherever they end up living out their adult lives. I examine how and why tropical corals produce offspring that vary in size, energy content, and symbiotic algal partnerships. I am interested in the interaction among characters as larvae experience different environments (e.g., high light and temperature) and progress through different stages of life (planktonic larvae, benthic larvae, metamorphosed settler). Answering these questions helps us better understand how species disperse and succeed across a range of environments and community assemblages.
A settled Agaricia humilis in visible light (left) and fluorescence (right). The coral is green due to green fluorescent protein contained in its tissues.