Project title

Starch-grain reference collection

Mentor's name(s)

Yajaira Núñez Cortés, Tupper Postdoctoral Fellow

Co-mentor's name(s)

Ashley Sharpe, STRI staff

Location of internship. Will mentor be at this location?

Center for Tropical Paleoecology and Archaeology. The mentor(s) will be at these locations.

Project summary

STRI has historically been a leader on archaeobotanical analysis in the Americas. The analysis of micro-remains, such as starch grains and phytoliths, has largely contributed to the identification of plant resources utilized by humans in the tropical Americas, an area with very poor preservation of macro-botanical remains. Larger and detailed reference collections permit not only the identification of plant resources but contribute to answer research questions related to the origins of domestication, the utilization of wild resources, the differential exploitation of the environment, the impact of human populations over the tropical forest, the types of processing of plant foods and identification of usable parts of the plant, among other questions. Archaeobotany is a quickly advancing and expanding field and this internship project will provide an essential tool for current and future work.
The purpose of this internship project is to 1) help create a digital reference collection of starch grains for economic plants likely utilized during pre-Columbian times in the tropical Americas, 2) provide experience for the next generation of archaeologists and archaeobotanists working in Central America. The creation of reference collections is essential for the accurate analysis and identification of archaeological samples, including those obtained from sediments, grinding tools, ceramics, and dental calculus from human and animal remains. Moreover, digital collections allow for proper curation and storage of the data, as well as facilitating sharing with other researchers and students working in the region.

Mentorship goals

The intern will learn the basics of starch grain analysis as well as the specific procedures for creating reference collections for this type of micro-remains. There are very few botanical specialists in Central America and even less digitized reference collections. The intern will not only learn the skill to create a reference collection, but they will also learn to differentiate between species and families based on the diagnostic features of the starch grains and, including shape, size, the presence of hilum, extinction cross, lamellae, and fissures. Developing this skill will be a crucial knowledge for future projects that we hope the intern undertakes with modern and archaeological samples.

Intern’s role, time commitment and expected products

The intern will work full-time, five days a week, on the reference collection. This will include the extraction of micro-remains from the plants (tubers, rhizomes, fruits, seeds) and their observation, photography, and video under the microscope and with the required polarizations. Starch grains are tridimensional remains, and as such, videos of them rotating will allow us to capture the variability within each plant. A desired background for the intern includes knowledge about Central American archaeology and interest in learning about archaeobotany. The internship will result on a digitized data base that will include the graphic materials, as well as descriptions of the diagnostic features of the starches per species and/or family. It is our hope that one or more papers can be published with the results of this project, and the intern will be a co-author. This work will be the basis for current projects at STRI, but we hope it may lead to continuous work on archaeological samples from tropical America.

Regularly held occasions for group discussions, attendance at lectures, career counseling, and other educational and experiential opportunities for interns

Several investigators will be present during them months of this internship. Monthly meetings for academic article discussions among investigators, fellows and interns at STRI will provide opportunities to broaden the internship knowledge about the archeology of Central America in general. The intern will also be encouraged to attend STRI lectures and seminars.

List of suggested readings

Cagnato, C., Hamon, C., Salavert, A., & Elliott, M. (2021). Developing a reference collection for starch grain analysis in Early Neolithic Western Temperate Europe. Open Archaeology, 7(1), 1035-1053.

Pagán-Jiménez, J.R. (2015). Almidones. Guía de material comparativo moderno del Ecuador para los estudios paleoetnobotánicos en el Neotrópico. ASPHA, Buenos Aires, Argentina.

Pearsall, D.M. (2016). Paleoethnobotany: a handbook of procedures. Routledge, London and New York.

Piperno, D.R., and Holst, I. (1998). The presence of starch grains on prehistoric stone tools from the humid Neotropics: Indications of early tuber use and agriculture in Panama. Journal of Archaeological Science 25: 765-776.

Piperno, D. R., Weiss, E., Holst, I., & Nadel, D. (2004). Processing of wild cereal grains in the Upper Palaeolithic revealed by starch grain analysis. Nature, 430(7000), 670–673.