ArticleProceedings of the National Academy of Sciences of the United States of America2013
Ecosystem variability and early human habitats in eastern Africa.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 20 papers.
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20 citing papers in PubMed, 160 citations in OpenAlex.
- BiomarkerProceedings of the National Academy of Sciences of the United States of America · 2026Article
- East African uplift as a catalyst for Middle Miocene faunal transitions.Science advances · 2025Article
- Advancing archaeological sedimentary lipid biomarker analysis: A review of recent developments and methodological guidelines.iScience · 2025Review
- New site at Olduvai Gorge (AGS, Bed I, 1.84 Mya) widens the range of locations where hominins engaged in butchery.Scientific reports · 2022Article
- Microbial biomarkers reveal a hydrothermally active landscape at Olduvai Gorge at the dawn of the Acheulean, 1.7 Ma.Proceedings of the National Academy of Sciences of the United States of America · 2020Article
- Savanna tree evolutionary ages inform the reconstruction of the paleoenvironment of our hominin ancestors.Scientific reports · 2020Article
- The emergence of emotionally modern humans: implications for language and learning.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2020Review
- Isotopic variance among plant lipid homologues correlates with biodiversity patterns of their source communities.PloS one · 2019Article
- Soil and plant phytoliths from thePeerJ · 2019Article
- Distinctions in heterotrophic and autotrophic-based metabolism as recorded in the hydrogen and carbon isotope ratios of normal alkanes.Oecologia · 2018Article
- Aridity and hominin environments.Proceedings of the National Academy of Sciences of the United States of America · 2017Article
- A progressively wetter climate in southern East Africa over the past 1.3 million years.Nature · 2016Article
- Changes in northeast African hydrology and vegetation associated with Pliocene-Pleistocene sapropel cycles.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2016Article
- A Pleistocene palaeovegetation record from plant wax biomarkers from the Nachukui Formation, West Turkana, Kenya.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2016Article
- Neogene biomarker record of vegetation change in eastern Africa.Proceedings of the National Academy of Sciences of the United States of America · 2016Article
- A synthesis of the theories and concepts of early human evolution.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2015Article
- A spring forward for hominin evolution in East Africa.PloS one · 2014Article
- Capturing climate variability during our ancestors' earliest days.Proceedings of the National Academy of Sciences of the United States of America · 2013Article
- Water, plants, and early human habitats in eastern Africa.Proceedings of the National Academy of Sciences of the United States of America · 2013Article
- Early human speciation, brain expansion and dispersal influenced by African climate pulses.PloS one · 2013Article
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3 authors at 2 institutions in 1 country.
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No grant is acknowledged in the PubMed record.
Abstract
The role of savannas during the course of early human evolution has been debated for nearly a century, in part because of difficulties in characterizing local ecosystems from fossil and sediment records. Here, we present high-resolution lipid biomarker and isotopic signatures for organic matter preserved in lake sediments at Olduvai Gorge during a key juncture in human evolution about 2.0 Ma--the emergence and dispersal of Homo erectus (sensu lato). Using published data for modern plants and soils, we construct a framework for ecological interpretations of stable carbon-isotope compositions (expressed as δ(13)C values) of lipid biomarkers from ancient plants. Within this framework, δ(13)C values for sedimentary leaf lipids and total organic carbon from Olduvai Gorge indicate recurrent ecosystem variations, where open C(4) grasslands abruptly transitioned to closed C(3) forests within several hundreds to thousands of years. Carbon-isotopic signatures correlate most strongly with Earth's orbital geometry (precession), and tropical sea-surface temperatures are significant secondary predictors in partial regression analyses. The scale and pace of repeated ecosystem variations at Olduvai Gorge contrast with long-held views of directional or stepwise aridification and grassland expansion in eastern Africa during the early Pleistocene and provide a local perspective on environmental hypotheses of human evolution.
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