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Thompson JC, Wright DK, Ivory SJ, Choi JH, Nightingale S, Mackay A, Schilt F, Otárola-Castillo E, Mercader J, Forman SL, Pietsch T, Cohen AS, Arrowsmith JR, Welling M, Davis J, Schiery B, Kaliba P, Malijani O, Blome MW, O'Driscoll CA, Mentzer SM, Miller C, Heo S, Choi J, Tembo J, Mapemba F, Simengwa D, Gomani-Chindebvu E. Early human impacts and ecosystem reorganization in southern-central Africa. SCIENCE ADVANCES 2021; 7:7/19/eabf9776. [PMID: 33952528 PMCID: PMC8099189 DOI: 10.1126/sciadv.abf9776] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
Modern Homo sapiens engage in substantial ecosystem modification, but it is difficult to detect the origins or early consequences of these behaviors. Archaeological, geochronological, geomorphological, and paleoenvironmental data from northern Malawi document a changing relationship between forager presence, ecosystem organization, and alluvial fan formation in the Late Pleistocene. Dense concentrations of Middle Stone Age artifacts and alluvial fan systems formed after ca. 92 thousand years ago, within a paleoecological context with no analog in the preceding half-million-year record. Archaeological data and principal coordinates analysis indicate that early anthropogenic fire relaxed seasonal constraints on ignitions, influencing vegetation composition and erosion. This operated in tandem with climate-driven changes in precipitation to culminate in an ecological transition to an early, pre-agricultural anthropogenic landscape.
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Affiliation(s)
- Jessica C Thompson
- Department of Anthropology, Yale University, New Haven, CT, USA.
- Institute of Human Origins, P.O. Box 874101, Tempe, AZ 85287, USA
| | - David K Wright
- Department of Archaeology, Conservation and History, University of Oslo, Oslo, Norway.
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xian, China
| | - Sarah J Ivory
- Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA, USA.
| | - Jeong-Heon Choi
- Department of Earth and Environmental Sciences, Korea Basic Science Institute, Ochang, Republic of Korea
| | - Sheila Nightingale
- Department of Anthropology, City University of New York, Graduate Center, New York, NY, USA
| | - Alex Mackay
- Centre for Archaeological Science, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Flora Schilt
- Institute for Archaeological Sciences and Senckenberg Centre for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany
- Universidade do Algarve, Interdisciplinary Center for Archaeology and Evolution of Human Behavior (ICArEHB), FCHS, Campus Gambelas, J27, Faro 8005-139, Portugal
| | | | - Julio Mercader
- Department of Anthropology and Archaeology, University of Calgary, Calgary, AB, Canada
- Max Planck Institute for the Science of Human History, Jena, Germany
- Institut Català de Paleoecologia Humana i Evolució Social (IPHES), Zona Educacional, 4-Campus Sescelades URV (Edifici W3), 43007 Tarragona, Spain
| | | | - Timothy Pietsch
- Australian Rivers Institute, Griffith University, Brisbane, QLD, Australia
| | - Andrew S Cohen
- Department of Geosciences, University of Arizona, Tucson, AZ, USA
| | - J Ramón Arrowsmith
- School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA
| | - Menno Welling
- Reinwardt Academy, Amsterdam University of the Arts, Amsterdam, Netherlands
- African Heritage Ltd., Box 622, Zomba, Malawi
| | | | | | - Potiphar Kaliba
- Malawi Department of Museums and Monuments, Lilongwe, Malawi
| | - Oris Malijani
- Malawi Department of Museums and Monuments, Lilongwe, Malawi
| | - Margaret W Blome
- Department of Geological Sciences, East Carolina University, Greenville, NC, USA
| | - Corey A O'Driscoll
- Centre for Archaeological Science, School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Susan M Mentzer
- Institute for Archaeological Sciences and Senckenberg Centre for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany
- School of Anthropology, University of Arizona, Tucson, AZ, USA
| | - Christopher Miller
- Institute for Archaeological Sciences and Senckenberg Centre for Human Evolution and Palaeoenvironment, University of Tübingen, Tübingen, Germany
- SFF Centre for Early Sapiens Behaviour (SapienCE), University of Bergen, Bergen, Norway
| | - Seoyoung Heo
- Department of Earth and Environmental Sciences, Korea Basic Science Institute, Ochang, Republic of Korea
| | - Jungyu Choi
- Gyeongju National Research Institute of Cultural Heritage, Gyeongju, Republic of Korea
| | - Joseph Tembo
- Malawi Department of Museums and Monuments, Lilongwe, Malawi
| | | | - Davie Simengwa
- Lanujos Social Research and Consultancy, Blantyre, Malawi
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Magill CR, Eglinton G, Eglinton TI. Isotopic variance among plant lipid homologues correlates with biodiversity patterns of their source communities. PLoS One 2019; 14:e0212211. [PMID: 30811453 PMCID: PMC6392421 DOI: 10.1371/journal.pone.0212211] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 01/29/2019] [Indexed: 11/18/2022] Open
Abstract
Plant diversity is important to human welfare worldwide, and this importance is exemplified in subtropical and tropical [(sub)tropical] African savannahs where regional biodiversity enhances the sustaining provision of basic ecosystem services available to millions of residents. Yet, there is a critical lack of knowledge about how savannahs respond to climate change. Here, we report the relationships between savannah vegetation structure, species richness, and bioclimatic variables as recorded by plant biochemical fossils, called biomarkers. Our analyses reveal that the stable carbon isotope composition (δ13C) of discrete sedimentary plant biomarkers reflects vegetation structure, but the isotopic range among plant biomarkers–which we call LEaf Wax Isotopic Spread (LEWIS)–reflects species richness. Analyses of individual biomarker δ13C values and LEWIS for downcore sediments recovered from southeast Africa reveal that the region’s species richness mirrored trends in atmospheric carbon dioxide concentration (pCO2) throughout the last 25,000 years. This suggests that increasing pCO2 levels during post-industrialization may prompt future declines in regional biodiversity (1–10 species per unit CO2 p.p.m.v.) through imminent habitat loss or extinction.
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Affiliation(s)
- Clayton R. Magill
- Lyell Centre, Heriot-Watt University, Edinburgh, United Kingdom
- Geological Institute, ETH Zürich, Zurich, Switzerland
- * E-mail:
| | - Geoffrey Eglinton
- Department of Earth Sciences, University of Bristol, Bristol, United Kingdom
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