Open AccessSedimentary biomarkers reaffirm human impacts on northern Beringian ecosystems during the Last Glacial period
Author(s) -
Vachula Richard S.,
Huang Yongsong,
Russell James M.,
Abbott Mark B.,
Finkenbinder Matthew S.,
O'Donnell Jonathan A.
Publication year - 2020
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/bor.12449
Subject(s) - beringia , glacial period , megafauna , last glacial maximum , period (music) , geology , physical geography , climate change , archaeology , ecology , earth science , paleontology , geography , oceanography , pleistocene , biology , physics , acoustics
Our understanding of the timing of human arrival to the Americas remains fragmented, despite decades of active research and debate. Genetic research has recently led to the ‘Beringian standstill hypothesis’ ( BSH ), which suggests an isolated group of humans lived somewhere in Beringia for millennia during the Last Glacial, before a subgroup migrated southward into the American continents about 14 ka. Recently published organic geochemical data suggest human presence around Lake E5 on the Alaskan North Slope during the Last Glacial; however, these biomarker proxies, namely faecal sterols and polycyclic aromatic hydrocarbons ( PAH s), are relatively novel and require replication to bolster their support of the BSH . We present new analyses of these biomarkers in the sediment archive of Burial Lake (latitude 68°26′N, longitude 159°10′W m a.s.l.) in northwestern Alaska. Our analyses corroborate that humans were present in Beringia during the Last Glacial and that they likely promoted fire activity. Our data also suggest that humans coexisted with Ice Age megafauna for millennia prior to their eventual extinction at the end of the Last Glacial. Lastly, we identify fire as an overlooked ecological component of the mammoth steppe ecosystem.