This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2019, Research Using Biological Collections. The fellowship supports research and training of the fellow that will utilize biological collections in innovative ways. Fruit color plays an essential role in the life cycle of many plants by attracting animals who eat the fruits and carry the seeds away from the parent plant. Blue fruits are relatively rare, and some produce vivid colors without the use of pigments. They accomplish this via nano-scale structures in their cell walls that interfere with light to produce color. This research will identify new species that exhibit such structurally colored fruits, and describe the bio-physical mechanisms responsible for these colors. In addition, this work will examine the evolution of structural color in fruits from a group of trees native to Australia, the Indo-Pacific, and Southeast Asia. The project will inform our understanding of the evolution of rare traits (such as blue fruit color) as well as provide a platform for multi-disciplinary interaction between biologists, physicists, and material scientists. In addition, this work will provide training for the fellow and undergraduates who will be involved in the work. The project's findings will be disseminated through scholarly publications and conferences as well as to the public via outreach activities.
The paucity of known structurally colored fruits has limited hypotheses about the ecological function of structural color in fruits and the circumstances behind its evolution. Northeast Australia has a relatively high number of blue-fruited species, including two of the known structurally colored fruits, E. angustifolius and Delarbrea michieana. The fellow will rely on both herbarium and living collections in botanical gardens to 1) survey herbarium collections for new species that may exhibit structural color, 2) describe the biophysical mechanism behind structural color in new species using optical and transmission electron microscopy, and 3) test the hypothesis that structural color serves as an honest signal of high nutritional reward in Elaeocarpus using phylogenetic comparative methods. The fellow will quantify a variety of color, nutritional content, morphological traits, and cell wall nanostructures across Elaeocarpus. She will collaborate with an interdisciplinary team at the University of Colorado-Boulder and the University of Cambridge, train biology and physics undergrads, and participate in science outreach activities in both locations. The research has the potential for bioinspired and biomimetic engineering applications, and will improve our understanding of the origin, evolution, and ecology of rare structural colors.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
