The rise in sea level, drought, forest fires or even migrations of plants and animals due to the increase in temperatures were phenomena that European hunter-gatherers already experienced during the Mesolithic.
At that time, that occurred between 11,000 and 6,000 years ago, the last glacial period ended and, progressively, a warm and temperate climate was established that caused not only an increase in vegetation and biodiversity, but also the flooding of coastal areas due to the rise in sea level.
An investigation, published in the journal PLoS ONE and led by Philippe Crombé from the University of Ghent (Belgium), shows how all these climatic changes were reflected in the design of the stone tools manufactured in that period by hunter-gatherers.
“In response to the rapid warming of the climate around 11,500 years ago, hunter-gatherers along the southern North Sea (northwestern Europe) faced environmental changes similar to those we encounter today. By studying hunting equipment, it is shown how humans overcame these changes, ”says Crombé.
The researcher, sole author of the work, analyzed the microliths, lithic artifacts carved by humans, using a bayesian model to see how its design and use changed in relation to climate and environmental changes.
For it, compared 228 radiocarbon-dated deposits along the North Sea coast with the different shapes of the microliths (triangles, crescents, leaf-shaped, trapezoids, etc.) found in those places.
What the shapes of the stone reflect
The results confirmed that the shapes of these artifacts appear to be linked to short climatic events (produced between one and two centuries) but abrupt. An example of this is that triangle-shaped weapons were introduced after an abrupt cooling event in the early Mesolithic associated with erosion and forest fires.
A similar weather event1,000 years later, it coincided with the appearance of small laminar microliths and others retouched. A new trapezoid shape on the arrowheads appeared to replace older utensils when a third cooling and drought event occurred a millennium later.
In addition, the variation in the shapes of the stones was, according to the work, much more complex than previously thought. Crombé hypothesizes that the designs were developed primarily as a means of differentiating the groups that lived in the North Sea basin.
As sea levels rose and the former inhabitants of the North Sea basin were forced to occupy new areas, the territoriality between individuals grew competing for resources. The use of stones as symbols could indicate which groups each one belongs to.
Crombé P. (2019) "Mesolithic projectile variability along the southern North Sea basin (NW Europe): Hunter-gatherer responses to repeated climate change at the beginning of the Holocene”. PLoS ONE 14 (7): e0219094.
Via Ghent University.