A team of archaeologists, using modern engineering methods, tested stone tools made by our distant ancestors - Homo habilis (Homo habilis). As it turned out, our ancestors knew how to skillfully select stones for a certain type of activity.
In the Olduvai Gorge in northern Tanzania, simple stone tools created by Homo habilis have long been discovered in layers of sediment that formed about 1.8 million years ago. This early human, with mixed human-ape features, was already upright. About 1, 2 million years ago, it was replaced by Homo erectus (Homo erectus), capable of creating more complex stone tools.
Archaeologists working in Olduvai Gorge decades ago noticed that extinct ancient hominid humans preferred certain types of stone for certain types of tools. For example, quartzite was better suited for cutting tools with sharp "scaly" edges, while basalt and other volcanic rocks were better suited for larger chopping tools — hand axes.
University of Kent anthropologist Alastair Key and his colleagues have used modern engineering techniques to simulate material selection for Homo habilis and Homo Erectus instruments. The most common rocks for the manufacture of stone tools were selected as samples - basalt, shert (siliceous shale) and quartzite.
A special machine lowered each sharpened sample onto a 2 mm section of PVC pipe and recorded the amount of force required to cut it, as well as the area of the bent surface. To test the durability of the instruments, the researchers cut open oak branches.
Quartzite turned out to be the sharpest, from which Shert was not much "behind". Basalt has the lowest "cutting" characteristics. Apparently, our ancestors used quartzite and shert in the manufacture of high-speed tools for "fine" work, while the stronger basalt was better suited for stone axes.