NSF Postdoctoral Fellowship in Biology FY 2015

Jensen Megan M, San Jose CA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2015, Research Using Biological Collections. The fellowship supports a research and training plan for the Fellow to take transformative approaches to grand challenges in biology that employ biological collections in highly innovative ways. The title of the research plan for this fellowship to Megan Jensen is "Whale baleen: form, function, and filtration." The host institution for this fellowship is Stanford University, and the sponsoring scientist is Jeremy Goldbogen. Baleen whales are among the largest animals that have ever lived, and many of these oceanic predators achieve extreme body sizes despite filter-feeding solely on tiny organisms like krill. Baleen consists of plates that hang down from the roof of the mouth and fray on the interior edge; the resultant mat of fringe separates prey from the water. This feeding mechanism is thought to be highly efficient, but the fluid dynamics of baleen filtration are poorly understood. This project challenges the long-standing hypothesis of how baleen filters seawater using specimens from the Smithsonian Institution's National Museum of Natural History. In addition to increasing and perhaps correcting current theory of a fundamental life process in whales, some of which are endangered, the research results are likely to increase public awareness of marine resources and ocean conservation. The filtration mechanism used by baleen whales could have applications for industrial flexible meshes and filters inspired by baleen. This fellowship directly supports the Fellow's career goals of becoming a leader in bio-inspired research using biomimetic approaches to illuminate ecological and evolutionary principles and teaching the next generation of biologists to use approaches from engineering. The research engages several students from a local high school as lab assistants, giving them hands-on research experience before they apply to college. Baleen specimens from the four living families of baleen whales are being studied using CT scans to generate 3-dimensional print models of baleen for flow tank experiments. These baleen models are being used to determine the mechanism(s) of baleen filtration, measure prey capture efficiencies, and estimate optimal filtration speeds. Identifying potential differences in filtration mechanisms and efficiencies in different evolutionary lineages of baleen whales is needed to understand how baleen's unique feeding mechanism evolved in cetaceans and may illuminate the feeding processes that support the largest animals on the planet. This project requires collaborations with researchers at multiple institutions in a number of fields, including marine mammal ecology, morphology, biomechanics, and fluid dynamics. The research integrates the Fellow's background in fluid dynamics and ocean engineering with new techniques, including making morphological measurements from museum collections and using 3D-printed models for research.