Acheulean handaxes (sometimes spelled Acheulian) are large chipped stone objects which represent the oldest and longest-used formally shaped working tool ever used by human beings, both Neanderthals and our ancestors. Part of the Acheulean tradition tool kit of the Lower Paleolithic (a.k.a. Early Stone Age), handaxes are the first form-shaped tool used by hominins. Handaxes were used well into the Middle Paleolithic (Middle Stone Age), and date between about 1.76 million and 100,000 years ago.
Handaxes are large stone cobbles which have been roughly worked on both sides (called "bifacially worked") into an oval or triangular shape. They are pointed, or at least relatively pointy on one end, and some of those pointy ends are quite tapered. Some are triangular in cross-section, some are flat. In fact, there is a lot of variability within the category. Early handaxes, those made before about 450,000 years ago, are simpler than the later ones, which evidence finer flaking. But archaeologists are still unsure exactly what these tools were used for.
Acheulean Handaxe Distribution
The Acheulean handaxe is named after the St. Acheul archaeological site where they were first identified 150 years ago. Early handaxes, dated about 1.6 million years ago, are from eastern and southern Africa, at sites such as Konso-Gardula in Ethiopia, Olduvai Gorge in Tanzania, and Sterkfontein in South Africa.
Early handaxes have been associated with Homo ergaster (H. erectus) in Africa and Europe. The later ones seem to be associated with both H. erectus and early modern H. sapiens. Acheulean handaxes have been recovered from Africa, Europe, India, and (possibly) China.
Differences between Lower and Middle Stone Age Axes
If it is difficult for us to get our minds around the idea that the handaxe remained essentially unchanged for over a million and a half years, that's because they did change. There is evidence that over time, making handaxes became a refined procedure. In particular, early handaxes seem to have been sharpened by tip reduction alone, while later ones appear to have been resharpened along their entire form. Whether this is a reflection of the kind of tool that the handaxe had become, or of the increased stone-working capabilities of the makers, or probably a little of both, is currently unknown.
The earliest Acheulean handaxe yet found is from the Kokiselie 4 site in the Rift valley of Kenya, dated about 1.76 million years ago, as reported in Nature in September of 2011. The earliest handaxe technology outside of Africa, was identified at two cave sites in Spain, Solana del Zamborino and Estrecho del Quipar, dated about 0.9 million years ago.
Acheulean handaxes and their associated tool forms are not the first tools ever used: that would be Oldowan tradition, and they represent a suite of chopping tools which are cruder and simpler tools, thought to have been used by Homo habilis.
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