Rainforest foragers intensified plant use long before agriculture

[OKIsItJustMe]

https://www.gea.mpg.de/225457/foragers-intensify-plant-use?c=192964

May 20, 2026
New research shows pre-agricultural intensification of plant use in Pleistocene Sri Lankan rainforests

A new study published in Nature Ecology & Evolution examining human populations in Sri Lankan tropical rainforests shows that people’s consumption of plants began increasing thousands of years before the introduction of agriculture. The research focuses on human and animal remains dating from approximately 20,000 to 3,000 years ago and uses zinc isotope analysis of tooth enamel to reconstruct an organism’s position in the food web – known as a trophic position – and dietary composition.

The results show that humans consistently occupied an intermediate, omnivorous position in the food web, with diets including both animal and plant resources. However, over time, the isotope data reveal a gradual shift toward values associated with greater plant consumption. This trend begins in the Late Pleistocene and continues into the Holocene, far earlier than the first confirmed evidence for domesticated crops in the region. Rather than reflecting a sudden agricultural ‘revolution’, the findings point to a long-term process of plant engagement among rainforest hunter-gatherers.

“Our results show that plant use was not a late development linked to farming, but part of a much longer trajectory,” said Dr. Nicolas Bourgon, lead author of the study and postdoctoral researcher in the Department of Coevolution of Land Use and Urbanisation at the Max Planck Institute of Geoanthropology (MPI GEA). “These rainforest populations were already intensifying their use of plant resources thousands of years before agriculture appears in the archaeological record.”

The study builds on decades of archaeological work at key cave sites, including Fa-Hien Lena, Batadomba-lena, and Balangoda Kuragala, which have produced evidence for sustained human occupation of tropical rainforest environments over tens of thousands of years. While previous interpretations have often emphasized hunting, largely due to the preservation of animal remains and tools, direct evidence for plant consumption has remained limited because organic materials rarely survive in such settings.

…

Bourgon, N., Oelze, M., Amano, N. et al. Pre-agricultural intensification of plant use in Pleistocene Sri Lankan rainforests. Nat Ecol Evol (2026). https://doi.org/10.1038/s41559-026-03082-6

[GreatGazoo]

1. There is a great bit in the journal of some New England pilgrims

in which they are blissfully unaware of permaculture. It says something like:

'These people know nothing of agriculture and spend their days doing whatever they please. Fortunately God has blessed them with an abundance of grapes, raspberries, blueberries (on and on)... that grow wild in cleared land.'

The people of what became New England included Taino who brought their permaculture techniques up with them from the Amazon. We now know that corn was selectively bred about 11,000 years ago. How they kept it from cross pollinating back toward teosinte (the wheatlike grass) is unknown. Corn is about 20% of all the calories that all the agriculture in the world produces now.

[SWBTATTReg]

2. Wonder if the more intensive consumption of plant materials is due to over-consumption of animals, a trend that

in many historic times, occurred due to uncontrolled harvesting.