Sub-Milankovitch paleoclimatic and paleoenvironmental variability in East Africa recorded by Pleistocene lacustrine sediments from Olduvai Gorge, Tanzania

Plant wax biomarkers in human evolutionary studies

“…The interest in molecular fingerprinting plant biomarkers in archeological 49–55 and paleoanthropological 6–20,22,56 studies (Figure 3), lies in key advantages this technique holds over other proxies. Plant wax δ 13 C (Box 2) is not biased toward herbivore feeding behavior like that of tooth enamel, and lipid biomarkers are more widespread than paleosol carbonates which only form in soils where annual rainfall is less than 1000 mm per year 57 .…”

“…This is particularly useful when ecological variability is studied alongside stone tool assemblages, the presence or absence of hominin‐modified bone, or instances of species turnover. In eastern Africa for example, relatively precise geochronology of archeological sequences and good preservation of wax biomarkers in paleo‐lake sediments have allowed for studies on short‐ and long‐term climate variability, 9 changes in response to aridity or humidity, 14 and plant landscape dynamics 18 …”

“…Plant wax data recovered in a lake core and lacustrine outcrops from Oldupai Gorge show changes in regional ecosystems between closed C 3 woodlands and open C 4 grasslands from 1.9 to 1.8 Ma, coinciding with precession cycle summer insolation maxima and minima 9,14,15 . Precession‐based fluctuations in rainfall influenced plant ecosystem changes, with drier conditions (Max δD C31 = −105 ‰; Avg.…”

“…While climatic and environmental variability have been prominently discussed in influencing the broad patterns of human evolution, 1–5 linking ecosystem changes to technological and behavioral responses remains challenging. To address such research challenges, the analysis of plant wax lipids from ocean and lake cores, 6–8 paleo‐lake drilling projects, 9–13 archeological and geological outcrops, 14–18 cave deposits, 19–21 and hominin‐bearing sediments 22 have the potential to provide well‐integrated, high‐resolution data on past plant ecology and environmental stresses in regions where hominins evolved.…”

Leaf Wax Lipid Extraction for Archaeological Applications

“…Plant wax lipid extraction and analysis is now being applied in archaeology contexts to investigate human‐environment interactions (Brittingham et al., 2019; Colcord et al., 2018; Collins et al, 2017; Connolly et al., 2019; Lupien et al., 2018; Magill, Ashley, & Freeman, 2013a, 2013b; Magill, Ashley, Domínguez‐Rodrigo, & Freeman, 2015; Patalano, 2019; Uno et al., 2016). Because n ‐alkanes and n ‐alkanoic acids record ancient environmental conditions through δ 13 C and δD ratios, they can track variations in hydroclimate, vegetation community and structure, and habitat type and be used to investigate human biological and cultural adaptive responses to ecological changes.…”