Jon Dombrosky Awarded GPSA New Mexico Research Grant
Posted: Nov 02, 2018 - 12:00am
Archaeology graduate student Jon Dombrosky has been awarded a high-priority GPSA New Mexico Research Grant for his study of the amino acid signature of maize in fishes from the late prehispanic Middle Rio Grande.
Doing initial stable isotope analysis on fish bones recovered from archaeological sites around the Albuquerque area, we found that some past fishes were eating much different foods than they do today. Specifically, they were eating arid adapted plants called C4 plants. This could mean that the prehispanic Rio Grande flooded more than it does today, and these flooding events were crucial for incorporating a variety of different nutrients into the past Rio Grande aquatic food web. Or it could mean that somehow corn was getting into the diet of fishes. It’s possible that Ancestral Pueblo agricultural fields, adjacent to the Rio Grande, decomposed and introduced a new source of energy for fishes to rely on. Using traditional stable isotope analysis to test if this was the case is near impossible. However, there is a new cutting edge technique called compound specific stable isotope analysis where we can actually measure multiple stable isotope values from amino acids and produce a fingerprint. My goal, with the help of some awesome students in Seth Newsome’s lab (Alexi Besser and Emma Elliott Smith), is to define the fingerprint of around 20 heirloom varieties of corn to see if it was somehow incorporated into their tissues.