William J. Pestle

WILLIAM PESTLE, University of Miami, Miami, Florida, was granted funding in October 2022 to aid research on “Assessing Foraging Behaviors and Paleoenvironmental Change among the Earliest Inhabitants of Southwestern Puerto Rico.” Recent archaeological fieldwork in the intertidal zone of southwestern Puerto Rico has revealed a landscape of over forty previously undocumented shell mounds (some as large as 4200 m2 and as tall as 10 m) formed by ancient humans depositing billions of marine shells in the same location. Carbon dates indicate that these mounds were formed between roughly 3000 and 1500 years ago, associating them with some of the earliest inhabitants of Puerto Rico. Undisturbed ancient landscapes of such size and density have no known parallels on the island. One of the most interesting aspects of these mounds is that over 90% of the shells in them come from marine habitats like coral reefs, but no such reefs are to be found anywhere near their location, which is instead presently dominated by mangroves and mudflats. Using a combination of archaeological and geological research techniques, we determined that the mounds were formed by humans gathering shellfish at a time when the local marine habitats were far different, meaning that the earliest inhabitants of this part of Puerto Rico were likely taking advantage of the most readily available resources when deciding what kinds of marine foods to gather.