On the Benthos: Studies of the Ecology & Evolution of Marine Invertebrates
Jackson Powell, Kevin Olsen and Isabelle Basden are students in the Department of Biological Sciences at FSU working together to study marine invertebrates using three very different perspectives. All three are active members in the FSU Academic Diving Program, and like many students in the program, they team up and share resources to ensure fieldwork is safe and efficient.
This summer operating from the FSU Coastal & Marine Lab (FSUCML), they have conducted research in local habitats from the shallow seagrasses of St. George Sound to natural and artificial reefs offshore of Dog Island. While Isabelle uses SCUBA to study sponges, Jackson and Kevin use diving to research tunicates, or seasquirts. Although their research will be written and presented independently, the cooperation while diving at the Marine Lab is essential.
Jackson Powell, a doctoral student in Dr. Scott Burgess’s lab, is researching the constraints of evolutionary responses to environmental change. He is interested in predicting when adaptive evolution will occur rapidly enough to keep up with unprecedented rates of anthropogenic environmental change. Key to addressing this uncertainty is knowledge of the constraints to adaptive evolution. Jackson believes that we have an incomplete understanding of how evolutionary constraints alter the speed of adaptation in species with complex life cycles. To investigate this, Jackson focuses on marine invertebrates because the majority have both pelagic and benthic stages. He creates families of seasquirts by mixing the sperm and eggs of different individuals with each other and then measures the traits of larvae and adults for each family in the lab. In doing this, he aims to reveal whether larval and adult traits are genetically correlated.
Kevin Olsen is a doctoral candidate advised by Dr. Don Levitan, who is interested in the ecological and evolutionary forces effecting how sessile marine invertebrates mate. Kevin’s dissertation focuses on the evolutionary dynamics of inbreeding and outbreeding in a sessile colonial seasquirt. He is studying how much inbreeding is occurring in immobile animals as a result of living in close proximity to relatives. Kevin uses SCUBA to record the position of seasquirts and to take tissue samples from every individual at a site. Inside the tissue samples are often larval offspring from the maternal parent, Kevin uses genetics to determine who the siring father is, the degree of relatedness between the parents, and the typical distance between reproductive partners. All these are important parameters when considering the conservation and management of similar marine invertebrates such as corals and sponges!
Isabelle Basden is an undergraduate directed by Dr. Janie Wulff studying the effects of filter feeding on water quality. For her honors thesis, Isabelle is researching how the active removal of suspended particles by sponges effects surrounding water quality. She studies sponge metabolism and filter feeding, the process of capturing food particles suspended in the water. As filter feeders, sponges play an important role in improving water quality and clarity. Isabelle use scientific diving to collect sponges for experiments from limestone reefs located directly off the marine lab. She is grateful that the FSUCML staff and graduate students are excited about and willing to accommodate undergraduate research!