Fecal stanol ratios indicate shifts in camelid pastoralism in the highlands of Peru across a 4,000-year lacustrine sequence

Subsistence adaptations respond to environmental instability as well sociopolitical demands. On the Andean altiplano, camelid husbandry is a key adaptation utilized for thousands of years mitigate risks agricultural productivity, facilitate transport and generate wealth political purposes. Here, we reconstruct history utilization on altiplano with fecal stanol biomarkers from Lake Orurillo in southern Peru. Biomarker samples span 4000-year interval document changes at centennial timescales. The abundances individual stanols appear be less diagnostic human occupation region where population levels apparently remained far lower than those domesticated camelids. However, ratios (coprostanol) ruminant (24-ethylcoprosanol) concentrations demonstrate that these proxies are reliable indicators variations herd sizes. Our data show intensified after ca. 1050 CE during severe protracted drought was coincident widespread movement away fertile farmlands higher elevations favorable grazing. Camelid herds high abundance around improved climate conditions through Inca era until 1500 when our point significant disruption European conquest. intensification among cultures therefore linked major shifts.