News Release

Climate change did not influence prehistoric survival techniques in the tropics

Peer-Reviewed Publication

Netherlands Organization for Scientific Research

One standard archaeological theory says that at the end of the last ice age prehistoric people in the tropics changed their stone tools so that they could focus on a wider range of food sources in addition to hunting. However, Dutch researchers have now discovered that there was in fact no such correlation between tools and the climatic change that took place ten thousand years ago. Their conclusion is based on a study of eight hundred flakes from sites in Colombia, namely on the high plains of Bogota, in the valley of the Magdalena river, and in the Amazon rain forest.

The assumption that inhabitants of the tropics adapted their technology as a result of climate change was based in part on flakes from another Colombian site, at Tequendama. Many different types of stone tools have been found there and archaeologists assumed that each of them had a special function. Flakes with concave edges, for example, were supposed to have been used for working wood. The increase in the number of flakes with concave edges after the last ice age was thought to be a direct result of the increased area of woodland in the Andes. This theory has now been shown to be untenable.

The Leiden University team which came to this conclusion were carrying out their research in the framework of a project organised by the NWO¹s Foundation for the Advancement of Tropical Research (WOTRO). Their main conclusion was that prehistoric man used his stone implements for a variety of functions, regardless of their shapes. They concluded this from the wear patterns on the implements and from microscopic fragments of hairs, collagen from bone, starch, pollen, and wood fibres which they found on them. The same types of implement would appear to have been used for hunting, butchering carcasses, and working wood. They were not in fact able to discover any correlation between the form and the function of the flakes. It was also notable that only somewhere between a quarter and half of the flakes had in fact been used.

The Leiden archaeologists also concluded that prehistoric man in the tropics had hardly engaged in any specialisation during the last ice age or in the first few centuries after it. Prehistoric peoples used flakes as and when they needed them, and with their simple tools were probably not dependent on any single environment, allowing them to survive either on the cool upland plateaus or in the tropical forests. The climate change taking place at the time therefore had no direct influence on their survival techniques.

###

Further information:
Channah Nieuwenhuis (University of Leiden)
T +31 20 622 8192
F +31 20 622 8192
E-mail: gerwie@vpro.nl or
E-mail: C.nieuwenhuis@arch.LeidenUniv.nl


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.