Tools of the Trade: Stone Tool Technology in Prehistory

Stone tools represent one of the most enduring and ubiquitous artifacts of human prehistory, spanning millions of years and encompassing diverse cultures, environments, and technological traditions around the world. From simple hand axes and flint flakes to finely crafted blades and projectile points, stone tools played a central role in the lives of our ancestors, shaping their economies, social structures, and cultural practices.

The use of stone tools by early humans dates back millions of years, with the earliest known stone tools found at sites such as Gona in Ethiopia, Lomekwi in Kenya, and Dikika in Ethiopia, dating back to around 3.3 million years ago. These primitive stone tools, known as Oldowan tools, were simple flakes and cores made by striking one stone against another to produce sharp edges for cutting, scraping, and butchering animal carcasses. Oldowan tools were used by early hominins such as Australopithecus and early members of the genus Homo, demonstrating the importance of tool use and technology in our evolutionary history.

The next major technological innovation in stone tool technology was the development of Acheulean handaxes, which emerged around 1.7 million years ago and persisted for over a million years until around 200,000 years ago. Acheulean handaxes were large, teardrop-shaped bifacial tools, often symmetrical in form, which were carefully crafted through a process of shaping, flaking, and polishing. These handaxes were versatile tools used for a wide range of tasks, including butchering, woodworking, and digging, and their standardized form suggests they were likely produced by skilled artisans using predetermined designs and techniques.

The emergence of Acheulean handaxes marked a significant advance in stone tool technology, reflecting the increased cognitive and manual dexterity of early hominins and their ability to plan and execute complex tasks. Acheulean handaxes were made using a variety of techniques, including percussion flaking, pressure flaking, and grinding, which required careful control of force, angle, and direction to shape and refine the stone. The production of Acheulean handaxes also required the selection of suitable raw materials, such as flint, chert, or quartzite, which were readily available and abundant in many parts of the world.

The Acheulean tradition persisted for hundreds of thousands of years and spread across Africa, Europe, Asia, and the Middle East, with regional variations in style, form, and technique. In Africa, Acheulean handaxes are found at sites such as Olorgesailie in Kenya, where hundreds of handaxes have been recovered along with evidence of butchery and hunting activities. In Europe, Acheulean handaxes are found at sites such as Boxgrove in England and Schöningen in Germany, where they are associated with early Homo species such as Homo erectus and Homo heidelbergensis. In Asia, Acheulean handaxes are found at sites such as Zhoukoudian in China and Attirampakkam in India, where they are associated with early hominin populations such as Homo erectus and Homo sapiens.

The end of the Acheulean tradition around 200,000 years ago marked the beginning of a new phase in stone tool technology, characterized by the emergence of the Middle Stone Age (MSA) in Africa and the Middle Paleolithic in Europe and Asia. During this period, stone tool technologies became more diverse and specialized, with the development of new tool types, such as blades, points, and scrapers, as well as new techniques, such as pressure flaking, heat treatment, and hafting.

Blades were one of the most significant innovations of the Middle Stone Age, representing a major advance in stone tool technology. Blades are elongated flakes with parallel edges and a sharp point, which were produced by striking a prepared core with a soft hammerstone or antler punch to detach long, thin flakes. Blades were highly versatile tools used for cutting, slicing, and piercing a wide range of materials, including animal hides, plant fibers, and wood. The production of blades required careful preparation of the core, precise striking techniques, and skillful manipulation of the flake to control its shape and size.

Points were another important innovation of the Middle Stone Age, used as spearheads, arrowheads, and other projectile tips. Points were typically made from flakes or blades that were retouched or modified to create a sharp, pointed tip suitable for penetrating flesh or hide. Points were often hafted onto wooden shafts or handles using adhesive resins, sinew, or cordage, creating composite tools that were effective weapons for hunting, fishing, and warfare. The production of points required skillful flintknapping techniques, as well as knowledge of local materials, hunting strategies, and tool design.

Scrapers were common tools used for processing animal hides, bone, and wood, as well as for scraping, smoothing, and shaping stone and other materials. Scrapers were typically made from flakes or blades that were retouched along one or more edges to create a sharp, serrated edge suitable for scraping and abrading surfaces. Scrapers were used for a wide range of tasks, including tanning hides, shaping wooden implements, and preparing plant fibers for cordage and weaving. The production of scrapers required careful selection of suitable raw materials, as well as skillful retouching and resharpening techniques to maintain the sharpness and effectiveness of the tool.

The Middle Stone Age saw the development of new techniques and technologies for stone tool production, including pressure flaking, heat treatment, and hafting. Pressure flaking involves applying controlled pressure to a stone flake with a pointed tool, such as an antler tine or bone awl, to remove small flakes and create a finely retouched edge. Pressure flaking was used to refine the edges of blades, points, and other tools, as well as to create delicate retouch patterns and fine details on the surface of stone tools. This technique allowed for greater precision and control in shaping stone tools, resulting in sharper edges and more efficient cutting and piercing capabilities.

Heat treatment was another important innovation in stone tool technology, particularly for enhancing the properties of raw materials such as flint and chert. Heat treatment involves heating stones to high temperatures and then rapidly cooling them, which alters their crystalline structure and makes them easier to flake and shape. Heat-treated stones are more durable, less brittle, and have improved fracture resistance, making them ideal for producing high-quality blades, points, and other tools. Heat treatment also allows for the use of a wider range of raw materials, including lower-quality stones that would otherwise be unsuitable for tool production.

Hafting, or the attachment of stone tools to handles or shafts, was another important innovation that allowed for the creation of composite tools with improved functionality and versatility. Hafting involved securing stone tools to wooden, bone, or antler handles using adhesive resins, sinew, or cordage, creating weapons such as spears, arrows, and axes that could be thrown or thrust with greater force and accuracy. Hafting also allowed for the attachment of stone tools to other materials, such as bone or antler, to create multi-component tools with specialized functions, such as harpoons, knives, and sickles.

The development of new stone tool technologies during the Middle Stone Age was driven by a combination of environmental, social, and cultural factors, including changes in climate, vegetation, and resource availability, as well as innovations in tool design, production techniques, and social organization. As early human populations expanded into new environments and encountered new challenges, they developed new strategies and technologies for exploiting resources, adapting to changing conditions, and interacting with their surroundings.

The Late Stone Age, or Upper Paleolithic period, witnessed further innovations in stone tool technology, as well as the emergence of symbolic expression, artistic creativity, and complex social behaviors. The Upper Paleolithic is characterized by the widespread use of finely crafted blades, points, and other tools made from high-quality raw materials such as obsidian, flint, and chert. These tools were often produced using advanced flintknapping techniques, such as pressure flaking and blade production, which allowed for greater precision and control in shaping stone tools.

One of the most iconic innovations of the Upper Paleolithic period was the development of the bow and arrow, a highly effective hunting weapon that revolutionized hunting strategies and techniques. The bow and arrow allowed early humans to hunt from a distance, reducing the risk of injury and increasing the likelihood of success. The invention of the bow and arrow required sophisticated knowledge of materials, woodworking, and projectile physics, as well as the development of specialized tools and techniques for crafting bows, arrows, and arrowheads.

The Upper Paleolithic period also witnessed the emergence of symbolic expression and artistic creativity, as evidenced by the rich legacy of cave art, portable artworks, and personal adornments found at sites across Europe, Asia, and Africa. Cave art, such as the paintings of Lascaux and Altamira, depict scenes of hunting, animals, and human figures, as well as abstract symbols and geometric motifs. Portable artworks, such as figurines, carvings, and engravings, depict a wide range of subjects, including animals, humans, and mythical creatures, as well as scenes of everyday life and ceremonial rituals. Personal adornments, such as beads, pendants, and bracelets, were made from a variety of materials, including bone, shell, ivory, and stone, and were often decorated with intricate patterns and designs.

The production of stone tools continued to evolve throughout the Holocene period, with the development of new materials, techniques, and technologies for shaping and refining stone tools. In some regions, such as the Americas, stone tool technologies persisted into historic times, with indigenous peoples continuing to use stone tools for a variety of tasks, including hunting, woodworking, and food processing. In other regions, such as Europe and Asia, stone tool technologies were gradually supplanted by metalworking technologies, such as bronze and iron, which offered greater durability, versatility, and efficiency in tool production.