NSF Postdoctoral Fellowship in Biology FY 2018

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2020, Research Using Biological Collections. The fellowship supports research and training of the Fellow that will utilize biological collections in innovative ways. One way to understand species and build evolutionary trees is through DNA analysis, but this method is can be expensive and laborious to scale to hundreds of geographically diverse specimens.

Spectral signatures are inexpensive datasets that reveal a tremendous amount of biological information by recording the interactions of visual and infrared light with leaf tissues. Just like DNA sequence analysis, spectral signatures can inform leaf physiology, species boundaries, and evolutionary relationships. This project will provide a novel approach and primary case study of the application of spectral signatures to museum collections.

It will teach undergraduate students from diverse backgrounds (especially first-generation academics) in the Chicago area to scan leaves in the Field Museum herbarium and then the Fellow will use the scans for species identification, taxonomy, and evolutionary analysis. The results will help speed up our understanding of biological diversity by coupling a powerful new technology with the wealth of biological specimens sitting in museum collections.

Specifically, this project will generate new genomic data and spectral signatures (400-2,500 nm) from herbarium and archaeological collections to refine hypotheses of the origins and domestication of coca (Erythroxylum spp.), a culturally significant South American crop and the natural source of cocaine. The Fellow’s previous phylogeographic research has shown that the four modern coca varieties originated from at least two independent domestication events from the wild progenitor E. gracilipes.

This project will add 198 more samples representing key geographic areas to the exon-capture DNA dataset and conduct statistical phylogeographic analyses. It will also incorporate spectral signatures made from ~1000 herbarium specimens plus 40 archaeological leaf remains up to 8,000-years old for high-resolution phenotypic analyses of modern and ancient coca leaves.

The project will also analyze spectral signatures from the other ~260 wild species in the Coca family and compare these to existing phylogenomic hypotheses to research the general utility of spectral signatures for species identification and phylogenetic inference. Thus, the PI will receive training in remote sensing as well as in population genetics; undergraduate students underrepresented in STEM disciplines will, in turn, gain herbarium and laboratory experience in these same areas of inquiry, refining our understanding of the systematics of the Coca family in the Neotropics and stimulating collections-based research using spectral signatures.

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.