Humans Were Changing the Planet 4,000 Years Earlier Than We Thought

Hadrian’s Wall, United Kingdom — one of many examples where humans had significantly changed the Earth’s surface nearly 2000 years ago. Credit: Lucas Stephens

Humans had caused significant landcover change on Earth up to 4000 years earlier than previously thought, University of Queensland researchers have found.

The School of Social Sciences‘ Dr. Andrea Kay said some scientists defined the Anthropocene as starting in the 20th century, but the new research showed human-induced landcover change was globally extensive by 2000BC.

The Anthropocene – the current geological age – is viewed as the period in which human activity has been the dominant influence on Earth’s climate and environment.

“The activities of farmers, pastoralists, and hunter-gatherers had significantly changed the planet four millennia ago,‘‘ Dr. Kay said.

The ArchaeoGLOBE project used an online survey to gather land-use estimates over the past 10,000 years from archaeologists with regional expertise.

‘‘The modern rate and scale of anthropogenic global change is far greater than those of the deep past, but the long-term cumulative changes that early food producers wrought on Earth are greater than many people realize,“ Dr. Kay said.

“Even small-scale, shifting agriculture can cause significant change when considered at large scales and over long time periods.“

Rice terraces, Ubud, Bali — farmers like them around the world have been modifying the Earth’s surface for thousands of years. Credit: Andrea Kay

Fellow researcher Dr. Nicole Boivin said the innovative crowdsourcing-from-experts approach to pooling archaeological data had provided the project with a unique perspective.

‘‘Archaeologists possess critical datasets for assessing long-term human impacts on the natural world, but these remain largely untapped in terms of global-scale assessments,“ Dr. Boivin said.

Another researcher on the team, Dr. Alison Crowther, said the study could help plan for future climate scenarios.

“This research and the collaborative approach we used means we can better understand early land use as a driver of long-term global environmental changes across the Earth‘s system,“ Dr. Crowther said.

For more on this topic, see Ancient Civilizations Were Already Messing Up the Planet.

Reference: “Archaeological assessment reveals Earth’s early transformation through land use” by Lucas Stephens, Dorian Fuller, Nicole Boivin, Torben Rick, Nicolas Gauthier, Andrea Kay, Ben Marwick, Chelsey Geralda, et al., 30 August 2019, Science.
DOI: 10.1126/science.aax1192

Dr. Kay, Dr. Boivin, Dr. Crowther, and UQ Senior Research Fellow Dr. Patrick Roberts each have joint appointments at UQ and The Max Planck Institute for the Science of Human History’s Department of Archaeology.

Other researchers on the team were UQ’s head of archaeology, Associate Professor Andrew Fairbairn, and archaeologists from Australian National University, the University of Melbourne, University of Sydney, Flinders University, and LaTrobe University.