[Paper] Reconstructing the environmental conditions experienced by early modern humans at Tam Pà Ling (northeast Laos) using higher plant wax biomarkers

via Quaternary Science Reviews, 01 February 2024: Research by McAllister-Hayward et al. on sediments from Tam Pà Ling cave in northeastern Laos has revealed the environmental conditions faced by early modern humans around 86,000 years ago. Analysis of higher plant wax biomarkers indicates that the first Homo sapiens in mainland Southeast Asia lived in a predominantly C3 forested landscape during marine isotope stages 5 to 4. Fluctuations in carbon isotope values suggest varying moisture levels, impacting the surrounding landscape and highlighting the adaptability of early humans to these environmental changes.

The sediments of Tam Pà Ling (TPL), northeastern Laos, have yielded the earliest evidence of Homo sapiens in mainland Southeast Asia (∼86 ka; marine isotope stage (MIS) 5 b) with a number of skeletal elements having been recovered from the sequence attesting to two populations of H. sapiens present in the vicinity between 77 ± 9 ka to 39 ± 9 ka. At present there has been very limited research into the environmental conditions that these populations encountered during MIS 5–4. In this study, we present the results of an analysis of higher plant biomarkers (n-alkanes and n-alkanols) from the sediments at TPL to reconstruct the palaeovegetation of the site and the human fossils. The n-alkane δ13C values demonstrate that H. sapiens encountered a predominantly C3 forest landscape in MIS 5 b-MIS 4 that prevailed until MIS 1. Observations of a fluctuation in δ13C values across MIS 5 b-MIS 1 (∼86–3 ka) indicates that moisture availability was non-uniform, most likely resulting in landscape changes in and around TPL. The presence of H. sapiens at TPL during the environmental conditions associated with MIS 5 b-MIS 3 highlights the adaptability of our species to environmental dynamics at this time.

Source: Reconstructing the environmental conditions experienced by early modern humans at Tam Pà Ling (northeast Laos) using higher plant wax biomarkers – ScienceDirect