Stone Age

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2

Geologic Epochs of the Stone Age

During the Stone Age, Earth experienced the most recent in a succession of ice ages, in which glaciers and sea ice covered a large portion of Earth’s surface. The most recent ice age period lasted from 1.8 million to 11,500 years ago, a period of glacial and warmer interglacial stages that is known as the Pleistocene Epoch. The Holocene Epoch began at the end of the ice age 11,500 years ago and continues to the present. See Geologic Time.

B

Stone Age Toolmaking Technology

Early hominids made stone artifacts either by smashing rocks between a hammer and anvil (known as the bipolar technique) to produce usable pieces or by a more controlled process termed flaking, in which stone chips were fractured away from a larger rock by striking it with a hammer of stone or other hard material. Later, especially during the last 10,000 years, other techniques of producing stone artifacts—including pecking, grinding, sawing, and boring—became more common. The best rocks for flaking tended to be hard, fine-grained, or amorphous (having no crystal structure) rocks, including lava, obsidian, ignimbrite, flint, chert, quartz, silicified limestone, quartzite, and indurated shale. Ground stone tools could be made on a wider range of raw material types, including coarser grained rock such as granite.

Flaking produces several different types of stone artifacts, which archaeologists look for at prehistoric sites. The parent pieces of rock from which chips have been detached are called cores, and the chips that have been removed from cores are called flakes. A flake that has had yet smaller flakes removed from one or more edges in order to sharpen or shape it is known as a retouched piece. The stone used to knock flakes from cores is called a hammerstone or a percussor. Other flaking artifacts include fragments and chunks, most of which are broken cores and flakes.

The terms culture and industry both refer to a system of technology (toolmaking technique, for example) shared by different Stone Age sites of the same broad time period. Experts now prefer to use the term industry instead of culture to refer to these shared Stone Age systems.

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III

Divisions of the Stone Age

Archaeologists have divided the Stone Age into different stages, each characterized by different types of tools or tool-manufacturing techniques. The stages also imply broad time frames and are perceived as stages of human cultural development. The most widely used designations for the successive stages are Paleolithic (Old Stone Age), Mesolithic (Middle Stone Age), and Neolithic (New Stone Age). British naturalist Sir John Lubbock in 1865 defined the Paleolithic stage as the period in which stone tools were chipped or flaked. He defined the Neolithic as the stage in which ground and polished stone axes became prevalent. These two stages also were associated with different economic and subsistence strategies: Paleolithic peoples were hunter-gatherers while Neolithic peoples were farmers. Archaeologists subsequently identified a separate stage of stone tool working in Eurasia and Africa between the Paleolithic and the Neolithic, called the Mesolithic. This period is characterized by the creation of microliths, small, geometric-shaped stone artifacts that were attached to wood, antler, or bone to form implements such as arrows, spears, or scythes. Microliths began appearing between 15,000 and 10,000 years ago at the end of the Pleistocene Ice Age.

The Paleolithic/Mesolithic/Neolithic division system was first applied only to sites in Europe, but is now widely used (with some modification) to refer to prehistoric human development in much of Asia, Africa, and Australasia. Different terminology is often used to describe the cultural-historical chronology of the Americas, which humans did not reach until some point between 20,000 and 12,000 years ago. However, there is a general similarity in the transition from flaked stone tools associated with prehistoric hunter-gatherers to both flaked and ground stone tools associated with the rise of early farming communities. The period in the Americas up to the end of the Pleistocene Ice Age about 10,000 years ago, when most humans were hunter-gatherers, is called Paleo-Indian and the subsequent, postglacial period is known as Archaic.

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Paleolithic

Archaeologists subdivide the Paleolithic into the Lower Paleolithic (the earliest phase), Middle Paleolithic, and Upper Paleolithic (the later phase), based upon the presence or absence of certain classes of stone artifacts.

A

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Lower Paleolithic

The Lower Paleolithic dates from approximately 2.5 million years ago until about 200,000 years ago. It includes the earliest record of human toolmaking and documents much of the evolutionary history of the genus Homo from its origins in Africa to its spread into Eurasia. Two successive toolmaking industries characterize the Lower Paleolithic: the Oldowan and the Acheulean.

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