Overview
- Peer-reviewed research in PLOS One reports unusually high nitrogen values in ancient Chincha Valley maize consistent with seabird guano fertilization.
- The team combined stable isotope analysis with seabird bone baselines and imagery linking seabirds, fish, and sprouting maize to argue for culturally recognized guano use.
- Researchers say access to rich deposits on the nearby Chincha Islands likely boosted harvests and helped elevate the kingdom’s regional influence, potentially shaping its incorporation into the Inca Empire.
- Independent archaeologists describe the findings as the first direct evidence of pre-Hispanic guano fertilization in the region.
- The authors note limits including complex sulfur isotope results and a narrow geographic sample and call for broader testing to map scale and continuity.