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date: 19 April 2019

Stone Tools: Their Relevance for Historians and the Study of Historical Processes

Summary and Keywords

From at least 3.4 million years ago to historic periods, humans and their ancestors used stone as the raw material for tool production. Archeologists find stone tools on all the planet’s habitable landmasses, even in its cold and ecologically sparse Arctic regions. Their ubiquity and durability inform archeologists about important dimensions of human behavioral variability. Stone tools’ durability also gives them the ability to contribute to the study of long-term historical processes and the deeper regularities and continuities underlying processes of change. Over the last two millennia as ceramics, livestock, European goods, and eventually Europeans themselves arrived in southern Africa, stone tools remained. As social, environmental, economic, and organizational upheavals buffeted African hunter-gatherers, they used stone tools to persist in often marginal landscapes. Indigenous Africans’ persistence in the environment of their evolutionary origins is due in large part to these “small things forgotten.” Stone tools and their broader contexts of use provide one important piece of information to address some of archaeology and history’s “big issues,” such as resilience in small-scale societies, questions of human mobility and migrations, and the interactions of humans with their environments. Yet, stone tools differ in important ways from the technologies historians are likely to be familiar with, such as ceramics and metallurgy, in being reductive. While ceramics are made by adding and manipulating clay-like substances, stone tools are made by removing material through the actions of grinding, pecking, or fracture. Metals sit somewhere in between ceramics and stone: they can be made through the reduction of ores, but they can also be made through additive processes when one includes recycling of old metals. Stone-tool technologies can also be more easily and independently reinvented than these other technologies. These distinctions, along with the details of stone tool production and use, hold significance for historians wishing to investigate the role of technology in social organization, economy, consumption, contact, and cultural change.

Keywords: stone tools, Africa, technology, historical processes, adaptation, cultural transmission

Why Should an African Historian Care about Stone Tools?

Stone tools reflect archetypal human behaviors; they are pragmatic, the skills to make and use them are not genetically transmitted and must be learnt, and their production requires varying degrees of planning and problem-solving skills. They enable humans to do what cannot be accomplished with teeth and nails alone. As a result, stone tools have literally shaped the course of human (pre)history.

Three broad inflection points describe key shifts in humans’ relationship with stone tools.1 Occasional stone-tool use, using stone implements for tasks that can otherwise be performed with teeth or nails, evolved sometime before 1.7 million years ago (mya) and left behind a stone-tool record with significant gaps across space and through time. Habitual stone-tool use, relying on stone tools for stereotypical everyday tasks, evolved sometime between 1.7 and 0.3 mya. Since < 0.3 mya, human ancestors had become obligatory stone-tool users, making and using stone artefacts for purposes that would otherwise be difficult or impossible to achieve. With the invention of fired ceramics, metallurgy, and the rise of complex social organizations in the last ten thousand years, humans adopted mixed strategies of occasional, habitual, and obligatory stone-tool use.

To truly accomplish a longue duree approach to historical-social research, one has to deal with archaeology and archaeology’s most durable, if inscrutable, stone-tool evidence. Stone tools are one of the few tangible links between history and prehistory. Stone tools have provided key information to address some of African archaeology and history’s long-standing research problems, which are the processes of social change resulting from cultural contact. In southern Africa, these debates are epitomized by what has become known as the “Kalahari debate.” The Kalahari debate was about southern African Bushman communities and their relations with the outside world over the last two millennia. The debate questioned the “pristineness” of populations depicted in the classic Kalahari ethnographies of the mid-20th century and their usefulness as analogues for prehistoric populations. Using stone tools from archaeological sites, archeologists have demonstrated that while some Bushman communities adopted stock herding from other groups as a minor supplement to their subsistence activities, others rejected animal husbandry and continued using stone tools and hunting wild animals.2 These data have helped problematize static and essentialist views of social and economic contact that presuppose cultures living in a time warp outside the regular flow of history. To fully understand the importance of stone tools for historical studies, one first needs to know what stone tools are.

What Are Stone Tools?

A stone tool is, in the most general sense, any tool made either partially or entirely out of stone. The two primary forms of stone tools are ground stone (coarse-grained stone ground either purposely or incidentally) and flaked stone (sharp-edged flakes struck from nodules of rock). Most flaked-stone tool assemblages (groups of stone tools) comprise five basic components: cores, flakes, retouched tools, percussors, and ground stone (see Figure 1). Cores are rocks with evidence for the removal of flakes on their surfaces. Percussors are used to initiate fractures on cores. Flakes are sharp-edged objects detached from cores by fracture. Retouched tools are flakes or flake fragments whose edges are modified by removing smaller flakes along their periphery. Ground stone comprises nodules of rock with surfaces shaped through abrasion or pecking and whose surfaces are typically used to process plant foods or to crush materials.

Stone Tools: Their Relevance for Historians and the Study of Historical ProcessesClick to view larger

Figure 1. Overview of main stone-tool components and conventions for their illustration.

Image by Justin Pargeter.

The rocks and minerals most suitable for flaked-stone tool production are brittle and uniform, allowing them to deform under pressure and to fracture predictably and reliably. Quartz, quartzite, flint, and obsidian are suitable for stone-tool making, but talc, chalk, and limestone typically are not. Suitable rocks are not universally available, nor do they necessarily occur in the same parts of the landscape as the other key resources (water, shelter, food). Archaeological evidence shows that humans often organized their movements and settlement strategies in order to access high-quality rocks for stone-tool production. Local rocks (sourced within c. 3–6 miles of a site) dominate most stone-tool assemblages, and archeologists usually focus on variations in distances of non-local rocks. Geochemical studies of obsidian (volcanic glass) found, for example, in Kenya’s Koobi region show a highly mobile and diversified pastoral population used watercraft to access and distribute obsidian nodules across the landscape.3 Faced with a lack of suitable rock, some groups are known to alter naturally occurring rocks by slowly heating them under controlled conditions to make them more brittle.

Archeologists have spent considerable time and effort to understand the possible range of prehistoric stone-tool production strategies. These strategies may inform toolmakers’ decision-making processes, their motor capabilities, and the social contexts in which this information was transmitted and practiced. Studies of production methods rely on rare ethnographic observations and on experimental evidence derived by replicating possible toolmaking scenarios and then carefully “reading” the resulting stone-tool evidence. Drawing from these direct observations, archeologists identify four major strategies broadly representative of the long-term evolution of stone-tool production. These are direct percussion on an anvil, in-hand or freehand percussion, pressure flaking, and punch percussion (see Figure 2). The implements that result from these production strategies take a wide range of shapes and sizes dependent on the rocks from which they are made, the contexts and tasks for which they are used, and the cultural contexts under which their production strategies are learnt and reproduced.

Stone Tools: Their Relevance for Historians and the Study of Historical ProcessesClick to view larger

Figure 2. Overview of major stone-tool-making strategies. Illustration courtesy of Kristin Walter.

Image by Justin Pargeter.

How Do Archeologists Know What They Think They Know about Prehistoric Stone Tools?

Despite their longevity, ubiquity, and importance for understanding historical processes, stone tools can be problematic to study. First, humans no longer depend on stone tools for survival nor do they use most modern tools for extractive tasks in the same way as their ancestors did stone implements. Second, the strategies necessary to make stone tools must be learnt through social reproduction and individual practice, because this information is not genetically encoded. Some stone-tool-making strategies take minutes to learn and are easily shared. Others can take extensive training and practice to master. Because of the large commitment of time and energy involved, today this knowledge is not widely accessible and is instead concentrated in the hands of a few skilled practitioners. Third, unlike in the biological sciences, specialists who study stone tools have no natural history models from which to build their methods and theories. Archeologists have had to invent the terms, methods of analysis, and concepts they use to describe and compare stone-tool evidence. As a result, stone-tool studies from different regions vary widely in how they approach this evidence.

Having few living stone-tool-using communities on which to rely, archeologists must refer to actualistic information—alternative sources in which stone-tool production, use, and discard are actually observed. These data derive from actual observations of stone-tool use in experiments, ethnographic research, historical documents, or from contextual evidence derived from the archaeological record. These observations help to establish parameters of variation that can be compared to and tested against the archaeological record to better understand prehistoric behavioral variability.

For over a century, archeologists and amateur prehistorians broke rocks to gain insight into stone-tool technologies. This field is broadly referred to as experimental archaeology and involves the act of replicating processes of stone-tool manufacture and use for the purpose of investigating archaeological hypotheses, questions, and methods. Such studies have a long and assorted history in archaeological research, with many of the earliest stone “knappers” concerned more with exploring the art of stone-tool production than pursuing formal scientific procedures and rigorous analysis. Beginning in the late 1960s and 1970s, the tide began to move away from informal analyses and toward the use of replicated stone tools to test hypotheses about stone-tool technology, to construct models against which archaeological observations could be compared, and to evaluate methods applicable to archaeological problems.

Modern experimental archaeology has provided several key insights into stone-tool production, use, and the contexts in which the tools are deposited in the archaeological record. Experiments have also led to several methodological improvements including the use of microscopy to detect stone-tool use-traces and residues. For example, drawing from experiments, archeologists have established a relationship between the characteristics of metal and stone-tool edges and the marks they produce when applied to bone.4 These data are useful for understanding the introduction and spread of metallurgy into regions where archaeological traces may otherwise be absent or ambiguous. Other experimental studies have helped archeologists to better understand the contexts in which stone tools were deposited and the possible factors affecting these contexts (see Figure 3). The remains of these experiments form the basis of a growing archive of reference collections against which archaeological specimens are compared.

Stone Tools: Their Relevance for Historians and the Study of Historical ProcessesClick to view larger

Figure 3. Goat trampling stone and bone tools in an experimental context. Further details on the experiment are available in Louis S. B. Leakey, The Stone Age Cultures of Kenya Colony (Cambridge, UK: Cambridge University Press, 1931).

Photograph by Justin Pargeter.

Archeologists have also applied experimental approaches to better understand the social contexts of stone-tool production and to aid in identifying technological variables important for stone tools’ differential selection and social transmission. They have provided direct insight into issues such as the roles of raw material variability, copying errors, social learning mechanisms, and how these factors interact to generate variability in the stone-tool record.

Experiments show that individuals learning to make stone tools often make mistakes when imitating or emulating their teachers or a stimulus. Studies have shown that skilled performance will also affect the ways in which nodules of rock are selected, the manner in which stone is reduced, and the amount of waste produced in the process of reducing stone. These errors introduce random variability into the stone-tool record. The combined effects of individual variation, copying error, and social transmission of stone-tool technologies have wider implications for patterns of cultural variability through demographic parameters (i.e., population size, density, and interconnectedness).5

Experimental archaeology has also helped to overturn long-held assumptions about different stone-tool production strategies’ learning costs, energetics, and efficiency. These aspects of the stone-tool record are difficult to judge by observing the archaeological record alone. Experimental observations of sharp cutting-edge production values, flake production rates, or the time required for a core’s reduction can provide useful insights into the relative costs and benefits of different stone-tool production strategies. For example, experiments show that some naïve subjects require upward of one hundred hours of dedicated one-on-one training and practice to make even the most rudimentary shaped stone tools; these results highlight the costs of this skill-intensive subsistence strategy.6 Laurel Phillipson’s study of post-Aksumite Ethiopian stone tools spanning most of the first millennium ad demonstrates how costly retaining stone-tool-making abilities can be. Phillipson argued that post-Aksumsite populations lost the abilities to systematically flake stone as they became increasingly reliant on metals and ceramics.7 The resulting archaeological traces show people’s use of random flaking strategies illustrating only a vague recollection that sharp edges could be obtained from flaked stone.

The ethnographic record has provided a rich but more limited set of evidence from which to gain insight into stone-tool production and use and their role in shaping social life. Most ethnographic observations of stone tools come from historical documents or are secondary references from contexts in which other raw materials such as plastics and metals were in widespread use. Few studies document communities who rely on stone tools for their subsistence and survival needs. Yet, those data that do exist show that human use and interactions with stone tools are nearly always structured by at least age and gender ranking, suggesting that some patterns of stone tool variability may hold deeper social meaning. For example, the rich record of stone-tool use among hide-workers in Ethiopia has helped archaeologists to unpack gender, skill, and ethnolinguistic variability and their complex relations to stone tools and craft activities.8 In Ethiopia, hide-workers’ choices of the stone sources to exploit, the equipment to use, and the techniques to enact become habituated through processes of apprenticeship and learning. Variations in the choice of which tools to make and use has produced several regional stone-tool styles in modern Ethiopia. The Ethiopian evidence shows that stone-tool technology is a process involving choices that reinforce and actively generate social structures. Yet ethnographic observations among Australian Western Desert Aborigines show that stone-tool users exhibit remarkable casualness and opportunism in their interaction with stone tools, manufacturing tools from raw materials near at hand and in response to immediate needs.9 Modern ethnographic analogies for stone tool production and use are clearly complex and variable. Other ethnographic observations are noted among horticulturalists, pastoralists, and former hunter-gatherers in Africa, New Guinea, and the Americas.10 These data help archeologists to better understand the parameters governing prehistoric stone-tool production, use, and selection and to better understand how stone-tool technologies are intertwined with social and historical processes.

Historical documents provide another key source of information about the use of stone tools. Many of these documents have helped overturn long-held assumptions about stone-tool production and use and helped to establish that in historical times various groups used stone tools, and in a few cases, people still used them into the 20th century. George Stow wrote in the late 19th century of quick and effortless stone-flaking strategies among Bushman groups in South Africa’s Western Cape Province, and he noted their techniques for the manufacture and use of poison-tipped stone arrowheads.11 In 1872, Dunn interviewed an old Bushwoman living in the southern Kalahari who showed the manner in which stone arrowheads were flaked and then attached to wooden handles with glue.12 Historical documents have also provided insight into the broader range of stone-tool functions, including the use of ground and bored stones to extract and process meat, inorganic items such as ochre, and plant foods. The use of ground stone is one of the few stone-tool technologies that continues to be used in 21st-century contexts. Many 18th- and 19th-century travelers in southern Africa met stone-using peoples and observed the functional differences between different types of stone tools, some even mentioning the perceived benefits of stone tools over metal implements.13

What Are These Named Artifact-Types, “Industries,” and “Cultures” about which Archeologists Write?

Stone tools vary in size, shape, and patterns of retouch, and archeologists use these attributes to register different tool types (see Figure 4).14 Attribute approaches start by observing a stone tool’s features (i.e., a flake’s size, shape, surface angles, or the frequency of residual outer rind or “cortex”). These features are then either measured, coded, or counted and used in quantitative or qualitative analyses to identify shared attribute clusters. The interpretation of attribute clusters is the subject of a vast and sometimes contradictory body of literature. Some studies use stone-tool attribute clusters to partition data into discrete artefact types or to identify different tool-production strategies, while others use them to determine how much reduction has taken place in a given stone-tool assemblage.15

Stone Tools: Their Relevance for Historians and the Study of Historical ProcessesClick to view larger

Figure 4. Examples of stone-tool types common at historical or near historical archaeological sites. A, backed tool; B, “outil écaillés,” “splintered pieces,” or “pieces esquillées”; C, small scrapers; D, stone bowl; E, stone pestle.

Image by Justin Pargeter.

Archeologists originally used stone-tool types to arrange assemblages into relative sequences in the absence of more direct dating methods. In large part, the importance of stone-tool types derives from their importance in such systematics. Yet, many of the types initially thought to specify specific periods are known to occur in more than one period, limiting their value as chronological markers. Typologies have since become more important as methods to compare and contrast stone-tool assemblages across space and time. The most basic stone-tool typologies, such as those that distinguish between flakes, cores, and retouched tools, remain valuable for sorting the large numbers of stone tools found at most archaeological sites. They also describe the basic units that are necessary to describe and track stone-tool variability in the archaeological record.

Archeologists have long debated the meaning of artefact types. Some studies link artefact types to specific functional categories. Function exerts obvious pressures on technology and some stone tools, such as the tips of hunting weapons, can be shaped to function in specific ways. Observations derived from living stone-tool users show that the distinctions between tool forms are not inherently equivalent to differences in the activities to which they can be applied. Residues (substance traces) and microwear (microscopic activity traces) on stone-tool surfaces are tangible evidence that have the ability to show how specific artefacts were used. For example, microwear studies demonstrate that a wide range of tool types were used to process woody materials in Holocene southern Africa, while combined residue and microwear analyses of ground stone from archaeological contexts in Libya reveal humans’ continued harvesting and processing of wild plant foods after the introduction of domesticated foods.16 These records provide detail on activities and subsistence behaviors difficult to otherwise detect in the archaeological record.

A stone tool’s shape can also arise out of stylistic concerns; that is, its form can signal socially important information, such as group affiliation or membership. Some archeologists argue that stone-tool typological variability represents cultural or ethnic group norms either as passive variability resulting from adherence to subconscious social norms or as actively encoded social information. For example, Phillipson used details on stone-tool production strategies and implement morphologies to track pre-Aksumite agro-pastoral populations’ south-eastward movement into Northern Ethiopia starting in the fifth millennium bc.17 Such studies view stone-tool evidence as a direct extension of history and historical processes, and as such they are typically referred to as culture historical approaches.

Industries, Technocomplexes, and Age-Stages

Specialists have an elaborate lexicon to describe the archaeological record’s abundant stone-tool evidence. Many of the traditional terms used to describe stone tools are used to simplify the process of communicating information about stone tools. When engaging with the literature on African stone tools, historians are most likely to encounter terms such as Later Stone Age or Neolithic. These are terms that archeologists use to describe large-scale patterning in stone-tool evidence and to which this article will return later. Some terms are the products of historical coincidences, such as the location at which prehistorians first discovered a stone-tool type (i.e., archeologists named the Elmenteitan Neolithic [an early food-producing ‘culture’ in East Africa] after the region in Western Kenya from which artefacts belonging to this grouping were first formally described in 1931).18 Archeologists borrow other concepts, such as the terms used to describe the way rocks fracture under bending and compressive forces from the field of fracture mechanics. The stone-tool lexicon is widely variable and dependent on regional research traditions, because no universally acceptable set of concepts has yet been agreed upon to describe stone tools beyond those related to fracture mechanics.

Archeologists regularly use named stone-tool types to communicate information about the archaeological sites at which they are found and to identify higher-order groupings in stone-tool evidence commonly referred to as industries, technocomplexes, and age-stages. This approach sees stone-tool types as indicative of time and space within the archaeological record and as representative of specific cultural traditions.

Stone tool “industries” refer to groups of stone-tool assemblages with shared patterns of named stone-tool types and production strategies. Archeologists originally devised the “industries” concept as a means to describe and compare stone tools at a time when absolute dating techniques were either unavailable or had not yet reached widespread use. The concept of the stone tool “industry” derives from 18th- and 19th-century European society and its view of technology derived from the time’s rapidly industrializing technological contexts. When early European prehistorians looked around them, they saw swiftly changing industrial-era systems of raw material procurement, divisions of labor, manufacturing norms, mass production embodied in linear assembly lines, and the rise of factory systems. These contexts influenced the way early prehistorians viewed stone-tool technologies and the terms and concepts they used to describe this evidence. For example, many of the words archeologists use to describe stone tools (i.e., hammer, pick, scraper) were originally terms for industrial-era metal tools. The title “flintknapper” is widely used to refer to stone workers who replicate prehistoric stone tools and originally referred to industrial-era specialists, usually men, who made gun flintlocks.19

Technocomplexes (also known as “industrial complexes”) are groups of stone-tool industries that share tool-production strategies but differ in other respects such as the types of tools produced.20 Technocomplexes typically cover vast regions and they can span several millennia. Graham Clark’s “technological modes one to five” framework describes archaeology’s more widely used technocomplexes. It describes the progression from core and flake technologies (mode one) to small (miniaturized) stone-flaking systems (mode five) (see Figure 4). Archeologists elevate some stone-tool industries to the status of technocomplexes if they are discovered at several sites and across wide regions. Technocomplexes are a useful heuristic for communicating large-scale patterning in the stone-tool record, but archeologists struggle to equate their patterning with any known range of human cultural variability.

Stone ages refer to extended periods in which distinctive sets of technocomplexes were made. Shifts between these ages are commonly thought to represent “revolutions” or “transitions,” with older technologies replaced by newer and “better” ones in a linear fashion. Many of the inequitable views of some stone tools as better than others result directly from this perspective. Goodwin and van Riet Lowe created the first age-stage divisions for southern Africa, dividing that region’s stone-tool evidence into Earlier, Middle, and Later Stone Ages, the latter including the Pastoral Neolithic (i.e., societies with shifting emphasis on food production).21 Their system, although a deliberate act of liberation from European systems of thought, drew directly from European systematics that carved the prehistoric record into Lower, Middle, and Upper Palaeolithic periods.22 Archeologists across Africa rapidly adopted Goodwin and van Riet Lowe’s age-stage divisions except those working in North Africa and Egypt, where the European divisions persisted well into the 20th century. These divisions were borne more from North Africa’s close historical academic connections with Europe and the Near East than any truly unique aspect of these regions’ stone-tool records. Archeologists have attempted to bring greater resolution to the systematics arranging African stone-tool evidence, most famously the 1965 Burg-Wartenstein conference on African prehistory that attempted to dispense with the Early, Middle, and Later Stone Age system in favor of a more nuanced system of industries and industrial complexes.23 Despite these efforts, Goodwin and van Riet Lowe’s terminology remains deeply embedded within archaeological thinking about the African past.

Why Do Archeologists Explain Stone-Tool Variation Differently Today than Previously?

One of archaeology’s primary challenges is to document patterns and explain the root causes for stone-tool variability. To understand what archeologists do with lithic evidence today, one has to understand how archeologists have developed a long lineage of method and theory to interpret this evidence. So, today’s methods for studying stone tools include derivations from several prior epochs of stone-tool research, beginning with some of the first formal approaches dating to the 19th century.

Nineteenth-Century Index-Fossil Approaches

Modern efforts at interpreting stone-tool evidence follow a long history of thinking by 19th-century prehistorians. These earlier perspectives took stone-tool types as evidence for linear progressive change through time. Stone tools higher up in the sequence were seen as somehow better than those further down, reflecting progress and technological development through time. In the absence of direct methods for dating archaeological deposits and material remains, early prehistorians were compelled to use stone-tool types as “index-fossils” or “guide fossils” to help compare and contrast archaeological sites and regions. In geology, index-fossils refer to abundant and easily identifiable objects with wide geographic distributions and short chronological ranges. One major problem with using stone tools as index-fossils is that stone-tool shapes and production techniques can arise through processes other than direct cultural connectedness. Toolmakers living vast distances away from each other might produce stone tools that resemble one another and converge on the same result in the absence of any direct relationship. Although the index-fossil approach has obvious limitations in stone-tool studies, it remains a widely used method of discussing stone-tool evidence.

Twentieth-Century Culture-Historical Approaches Using Inventory Comparisons

Inventory approaches are formalistic and metric analyses that account for most stone-tool assemblage analyses. They focus on arranging stone-tool evidence into categories, quantifying these categories, and then using these summaries to compare and contrast different stone-tool assemblages. Archeologists typically use summary data on stone-tool types as the basic units of analysis in inventory approaches. The most common categories a historian might encounter when reading a stone-tool inventory are cores, flakes, and retouched tools. Subdivisions of these broad categories are often presented. The hope with inventory approaches is that standardized categorical data classes will enable simpler, more efficient stone-tool assemblage descriptions and comparisons.

Mary Leakey’s study of Earlier Stone Age stone-tool assemblages from Kenya’s Olduvai Gorge used an inventory approach, as did Janette Deacon’s study of Later Stone Age (LSA) hunter-gatherers in southernmost Africa.24 Archeologists have deployed Janette Deacon’s LSA stone-tool recording system in a wide range of proto-historical contexts to categorize, describe, and compare sites with stone-tool evidence relating to early animal herding groups and the last dedicated stone-tool-making and -using communities in southernmost Africa. North Africanist archeologists have employed inventory approaches borrowed from European studies to describe the stone-tool record of that region.

Inventory approaches have helped to standardize the language archeologists use to describe stone tools. Archeologists in parts of Africa with long-standing research traditions of using inventory approaches (e.g., North and southern Africa) struggle with fewer problems of widely varying descriptions and definitions. Inventory approaches are relatively easy to adopt and replicate, and they provide students and professionals alike with an efficient means of recording and reporting stone-tool data. Inventory approaches also have several drawbacks including their common lack of direct relevance to explaining changes in human behavior, clear guidelines on how to reform them, or how to interpret variability caused by the use of contrasting inventory approaches.

Later 20th-Century Adaptationist Perspectives

Later 20th-century archaeology tended to be more adaptationist; it focused on explaining the processes and social mechanisms that drive variability in the stone-tool record with respect to the differential survival of tool types and the populations who made them.25 Drawing on the wider availability of absolute dating techniques, an interconnected body of anthropological theory, and observations from modern ethnography, some archeologists interpret stone-tool variability in terms that emphasize its adaptive advantages relative to the social and ecological contexts in which tools are made and used. These approaches, grouped loosely under the “organization of technology” banner, weigh the design systems, costs, and benefits of various stone-tool-making strategies in relation to specific cultural and ecological contexts.26 By emphasizing time, energy, and ecological risk management as important factors influencing choices of technology, organization of technology approaches share much in common with behavioral ecology approaches to biological phenomena. Organization of technology approaches assume that prehistoric humans optimized their technologies by minimizing the costs of having a readily available toolkit while at the same time maximizing the benefits when deploying such a toolkit.

These models assume that all stone-tool production strategies have associated costs and benefits that are best understood in relation to the contexts in which the tools are made and used. For instance, hunting a buffalo with a bow and arrow entails a greater probability of loss than collecting marine molluscs. The costs and benefits associated with stone tools cannot be measured only through the direct use of a tool; they must consider other contextual factors. Typical contextual costs include finding rocks, transporting tools, maintaining implements, and investing time and energy to learn different toolmaking strategies. Risks include exhausting rock supplies, tool failure, or the failure of specific tool production strategies. Optimized technologies provide several payoffs, such as maximized resource acquisition rates, minimized production efforts, and increased production efficiency. Stone-tool technologies are rarely ever optimal, but by applying organization of technology models to behavior in the archaeological realm, archeologists hope to better evaluate and understand the contexts and decision-making processes governing stone-tool technologies when models are falsified or fail to fully account for observed archaeological patterns.27

Twenty-First-Century Technological and Social Evolutionary Approaches

Technological approaches document differences in stone-tool production strategies. Archeologists wishing to pursue technological studies draw on several different methods that include rejoining flakes to the cores from which they were struck, measuring and describing features on cores and flakes, conducting microscopic analyses on these products, and deducing aspects of the technological process from experimental observations. Technological approaches differ most from inventory approaches in viewing stone tools as meaningful not as individual pieces but within the context of an entire assemblage.

Some archeologists use the term “technology” broadly when referring to the patterned set of procedures that describe the ways prehistoric humans made stone tools.28 Other archeologists conceptualize stone-tool technologies as operational “chains” (from the French chaîne operatoire) describing the linear reduction sequence of changes from raw material procurement through to tool manufacturing, use, and discard.29 The chaîne operatoire approach seeks to not only describe technological sequences but also to explore technology’s broader social and cultural significance. Stone-tool production strategies must be learnt, practiced, and transmitted, and their patterning across time and space therefore holds significance for understanding changes in prehistoric social structures.

The original use of the reduction sequence concept proposed distinct and identifiable stages through which stone tools pass en route to becoming finished tools. The Levallois concept is a widely recognized set of technological concepts that describe the process of removing predetermined flakes (Levallois flakes) from cores whose surfaces have been shaped to produce ready-to-use flakes. When reporting on different reduction sequences, archeologists will describe the geological context, the techniques and methods used to produce the tools, and the sequence of steps required that account for the final products. Chaîne operatoire approaches typically conclude by studying the morphology of the resulting tools to deduce whether all steps are present for all rock types in an assemblage. If certain components are represented in certain rocks and not others, one might conclude that humans distributed reduction processes differentially across the landscape.

Identifying discrete stages in stone-tool production can be difficult, and some stone-tool technologies resemble continuous systems of interwoven strategies that feed dynamically from one another rather than progressing as linear chained systems.30 Moreover, production sequences can be dispersed across landscapes in accordance with raw material availability, group mobility, and the use to which stone tools are put. Despite these challenges, technological studies add nuance to stone analyses that are then better able to address the complex interrelationship between a toolkit’s various elements, their relationship to cultural change and ecological processes, and their variability across space and time.

Discussion of the Literature

Approaches to stone-tool analyses reflect contemporary anthropological concerns. Late-19th- and early-20th-century approaches emphasized “evolutionary” sequences among lithic assemblages.31 Prior to the 1960s, major research questions in stone-tool studies were largely culture-history oriented.32 They focused on describing similarities and differences among stone-tool industries and other archaeologically constructed entities.33 Research in the mid-20th century focused on categorical variation among stone tools, their assemblage structure, and sources of change and variability.34 Later 20th-century research placed increasing focus on systemic relationships among components of culture as seen through material traces—reflecting the rising use of systems thinking in behavior sciences.35 Following these trends, since the 1970s stone-tool analyses have increasingly sought to measure behavioral variability through examinations of settlement patterns, actualistic observations from experiments and ethnography, the organization of technology, and the link between these behaviors and larger evolutionary processes.36 These approaches look at strategic variability in stone-tool systems—at aspects of stone-tool variability that relate to other aspects of human behavior. These developments have brought stone-tool research more in line with the Longue Durée school of historical writing that seeks to uncover the meaning and organization of long-term structures. Two major shifts in human behavior occurred in Africa’s recent millennia with impacts on the questions both historians and archeologists could ask of stone tools and their variability. These are the origin and spread of food production and the eventual end of the Stone Age. The following sections provide brief overviews for each of these topics with suggestions for future research.

Hunter-Gatherers in a World of Food Producers

The last ten thousand years of African prehistory witnessed the continent’s transformation from a landscape of hunter-gatherers to the Africa of the 21st century, dominated as it is by food production. This process took several forms across Africa including resistance, coexistence, adoption of food production, displacement, and assimilation of stone-tool-using groups. In other parts of the world, this transition is generally referred to as the Neolithic (meaning new stone), referring to the new ways of making and using stone resources and particularly the increased emphasis on ground-stone technologies (i.e., grinding stones, mortars and pestles, ground-stone axes) linked to cereal agriculture, plant processing, and the need for implements sturdy enough to clear vegetation and forests. Africa’s Pastoral Neolithic period refers to the era in which several major reconfigurations took hold in the way humans made and used stone tools associated with hunter-gatherers’ interaction with livestock and food production.

Pastoralism was Africa’s earliest form of food production and it remains an economically important lifeway across the continent today. Pastoralism requires wide mobility and flexible patterns of resource acquisition that were well suited to the pre-existing hunter-gatherer way of life. Across eastern and southern Africa, for example, long-term stability in stone-tool production systems between c. 6000 cal. bc and cal. ad 500 occurred alongside dramatic shifts in subsistence systems, attesting to the success of stone adaptations in these settings. Gradual shifts involved the increased miniaturization of stone toolkits emphasizing geometric-shaped implements, some of which are impressively small (< 0.5 inches in maximum dimension). Blade segments are also commonly subjected to heavy reduction on anvils (see Figure 2), producing rectangular-shaped artifacts variably called “outil écaillés,” “splintered pieces,” or “pieces esquillées” (see Figure 4). These tool types are suggestive of efforts to conserve raw material, the processing of animal bone, and increased sedentism at archaeological sites of the time.

Broader changes in stone-tool technologies are suggested by geochemical sourcing of obsidian in Kenya’s Lake Victoria Basin, which shows as hunter-gatherer groups shifted toward more food production practices, they incorporated rocks and moved larger amounts of rock from more distant locations.37 These changes signal either the use of long-distance movement, exchange, or interactions between hunter-gatherer-fishers and herders who migrated into the region by ~ 2000 cal. bp.38 Archaeological data from southernmost Africa suggest that the arrival of agro-pastoralists into this part of Africa had a greater impact on stone-tool-using communities, with their eventual assimilation and disappearance in the 19th and 20th centuries.

Several questions remain to be answered regarding stone tools’ role in the transition to food production in Africa. One of the most pressing concerns regards generating more detailed comparative data from regions where pastoralism took hold more completely (i.e., the Sudanese Saharan region) versus those in which only certain elements were adopted (i.e., southernmost Africa). Other concerns include working toward a better understanding of how stone tools were used in different contexts related to food production and whether these practices shifted with the transition(s) from food extraction to food production. Studies seeking to better understand the role of stone tools under shifting mobility patterns could profitably be applied to this period, with its often-dramatic changes in the ways humans used landscapes.

The End of the Stone Age in Africa

The archaeological record’s last circa one thousand years provide important glimpses into the radically changing lives of stone-tool-using communities. Hunter-gatherers living in Africa, as opposed to Europe, reconfigured their lifeways, selectively modifying them as such in response to increasing degrees of contact and assimilation with indigenous African food producers and foreign colonial powers alike. The ensuing ethnically heterogeneous landscapes provide a rich set of case studies from which to investigate the evolving role of stone tools in diverse cultural settings.

Nothing speaks more clearly to stone tools’ energetic and strategic advantages than their persistence. Over the last two millennia as ceramics, livestock, European goods, and eventually Europeans themselves spread across Africa, stone tools remained a consistent albeit gradually diminished element. As social, environmental, economic, and organizational upheavals buffeted some hunter-gatherer groups, they used stone tools to persist in marginal landscapes. Indigenous Africans’ persistence in the environment of their evolutionary origins is due in large part to these “small things forgotten.” Historical documents support a more complex interpretation of this contact period, with some forager groups living in villages with livestock and agriculture.39 Remains of historical stone-tipped arrows show the continued importance of these technologies in historical contact situations (see Figure 5). The stone residues that remain from these various interaction scenarios help archeologists to address questions about complex processes of cultural change.

Stone Tools: Their Relevance for Historians and the Study of Historical ProcessesClick to view larger

Figure 5. Close-up view of two historical arrowheads with miniaturized stone inserts from the Pitt-Rivers Museum, Oxford.

Photograph by Justin Pargeter.

Excavations of farmer settlements in southernmost Africa have revealed tightly clustered and discrete stone-tool scatters reminiscent of the tool forms and technologies found at hunter-gatherer sites. The data suggest that when hunter-gatherers entered these farmer homesteads their activities were subject to local socio-spatial rules.40 The spatial patterns add complexity to discourses about the relations between hunter-gatherers and food producers and lead one to ask how and under what conditions could hunter-gatherers transcend boundaries between these communities. The possibility of drawing on some hunter-gatherer group’s ability to ritually mediate nature, especially for the benefit of rainmaking, would have obvious attractions for agro-pastoral communities.41

The end of the Stone Age is a period with great potential for addressing some of archaeology’s more nuanced questions regarding the role of stone tools in human societies in flux. Two major lines of inquiry could benefit from further analyses. The first regards the functions to which stone tools were put under shifting socioeconomic conditions. The widespread persistence of stone scrapers, a tool form commonly linked to hide preparation, into the 20th century is one obvious example worthy of further study. Microscopy, micro-residue, and technological analyses could add much-needed functional detail on these tools. Linking these data to contemporary studies of gender and hide-working could lead to important insights into the socioeconomic dimensions of activities associated with stone-tool use and discard.

Greater attention to the spatial location of stone-tool scatters within food production contexts could be further explored to examine the purpose and intent of forager-farmer interactions. Adding to these data, knowledge of how space functions within specific ethnolinguistic groups would add much-needed complexity to the debates about the assimilation of stone-tool-using groups into agro-pastoral societies. These data could be used to investigate the sociocultural dimensions of stone-tool technologies’ transmission, thereby bringing historical and evolutionary approaches closer together. By understanding the spatial distribution of stone-tool production debris across landscapes, one could gain further insight into the movements and activities of tool-using groups in ethnically diverse landscapes. The presence of only retouched tools on the one hand or complete stone-tool production sequences on the other could indicate unique interaction scenarios played out at landscape scales. More closely aligning such studies with ethnographic documents and historical sources would allow archeologists to interpret the intent and purpose of these patterns.

Primary Sources

• Examples of Museum Resources

  1. a. Smithsonian Museum

• Other Online Resources

  1. a. Freely available introductory text on stone tool technology, by Inizan and colleagues

  2. b. Catalogue and historical documenting of Stone Age Artefacts from Southern Africa in the British Museum, by Peter Mitchell

  3. c. Video tutorials on making and interpreting stone tools:

    1. i. Thin Biface Reduction, by Dr Chris Clarkson with commentary

    2. ii. Making Stone Tools, Big History Project

    3. iii. Stone Tools and the Evolution of Human Behaviour

    4. iv. Stone Tool Technology of Our Human Ancestors, HHMI BioInteractive Video

    5. v. ARPA 104 knapping demo

Further Reading

Andrefsky, William. Lithics: Macroscopic Approaches to Analysis. Cambridge Manuals in Archaeology. Cambridge, UK: Cambridge University Press, 1998.Find this resource:

Barham, Lawrence S., and Peter J. Mitchell. The First Africans: African Archaeology from the Earliest Toolmakers to Most Recent Foragers. Cambridge, UK: Cambridge University Press, 2008.Find this resource:

Dibble, Harrold L., et al. “Major Fallacies Surrounding Stone Artifacts and Assemblages.” Journal of Archaeological Method and Theory 24, no. 3 (2016): 1–39.Find this resource:

Geneste, Jean M. “Technical Systems of Lithic Production: Techno-Economic Variation in the Process of Realization of Paleolithic Tools.” Technique & Culture 17, no. 18 (1991): 1–36.Find this resource:

Gould, Richard. A. Living Archaeology. Cambridge, UK: Cambridge University Press, 1980.Find this resource:

Holdaway, Simon, and Nicole Stern. A Record in Stone: The Study of Australia’s Flaked Stone Artifacts. Melbourne, Australia: Museum Victoria, 2004.Find this resource:

Lemonnier, Pierre. “The Study of Material Culture Today: Toward an Anthropology of Technical Systems.” Journal of Anthropological Archaeology 5, no. 2 (1986): 147–186.Find this resource:

Odell, George. H. Lithic Analysis. New York: Kluwer, 2004.Find this resource:

Shea, John. J. Stone Tools in Human Evolution: Behavioral Differences among Technological Primates. Cambridge, UK: Cambridge University Press, 2017.Find this resource:

Shennan, Stephen J. Archaeological Approaches to Cultural Identity. London: Routledge, 2003.Find this resource:

Tostevin, Gil B. Seeing Lithics: A Middle-Range Theory for Testing for Cultural Transmission in the Pleistocene. Oakville: Oxbow Books, 2012.Find this resource:

Whittaker, John C. Flintknapping: Making and Understanding Stone Tools. Austin: University of Texas Press, 1994.Find this resource:


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