LAUSR

Abstract The ecological context of human societies living in tropical North America between the terminal Pleistocene and Holocene is of significant interest to scholars studying the last Pleistocene continental colonization of our species and, eventually, the emergence of agriculture in the Americas. However, there are currently few records of direct relevance to human behaviour with which to study environmental change across this crucial period. Here, we present stable carbon and oxygen isotope data from the tooth enamel of small- and medium-sized game from the archaeological site of Santa Marta Cave (Chiapas, Mexico) which spans the terminal Pleistocene/Holocene boundary (~11,340–11,280 cal. years BP) until the Mesoamerican Classic period. The results demonstrate that there was a persistent mixture of tropical environments in the vicinity of the site, from canopy forest to grassland, throughout this period. We argue that the presence of such tropical ecotones in southern Mexico, further supported by existing palaeoenvironmental datasets and palaeoclimatic modelling, enabled long-term resilient foraging, and highlights the increasingly-recognised importance of such habitats for forager-farmer transitions in the tropics.