Paleolithic (2.5 million – 10,000 BC)
The use of tools by early humans was partly a process of discovery, partly of evolution. Early humans evolved from a race of foraging hominids which were already bipedal,[12] with a brain mass approximately one third that of modern humans.[13] Tool use remained relatively unchanged for most of early human history, but approximately 50,000 years ago, a complex set of behaviors and tool use emerged, believed by many archaeologists to be connected to the emergence of fully-modern language.[14]
Stone tools
Human ancestors have been using stone and other tools since long before the emergence of Homo sapiens approximately 200,000 years ago.[15] The earliest methods of stone tool making, known as the Oldowan "industry", date back to at least 2.3 million years ago,[16] with the earliest direct evidence of tool usage found inEthiopia within the Great Rift Valley, dating back to 2.5 million years ago.[17] This era of stone tool use is called the Paleolithic, or "Old stone age", and spans all of human history up to the development of agriculture approximately 12,000 years ago.
To make a stone tool, a "core" of hard stone with specific flaking properties (such asflint) was struck with a hammerstone. This flaking produced a sharp edge on the core stone as well as on the flakes, either of which could be used as tools, primarily in the form of choppers or scrapers.[18] These tools greatly aided the early humans in theirhunter-gatherer lifestyle to perform a variety of tasks including butchering carcasses (and breaking bones to get at the marrow); chopping wood; cracking open nuts; skinning an animal for its hide; and even forming other tools out of softer materials such as bone and wood.[19]
The earliest stone tools were crude, being little more than a fractured rock. In the Acheulian era, beginning approximately 1.65 million years ago, methods of working these stone into specific shapes, such as hand axes emerged. The Middle Paleolithic, approximately 300,000 years ago, saw the introduction of the prepared-core technique, where multiple blades could be rapidly formed from a single core stone.[18] The Upper Paleolithic, beginning approximately 40,000 years ago, saw the introduction of pressure flaking, where a wood, bone, or antler punch could be used to shape a stone very finely.[20]
Fire
The discovery and utilization of fire, a simple energy source with many profound uses, was a turning point in the technological evolution of humankind.[21] The exact date of its discovery is not known; evidence of burnt animal bones at the Cradle of Humankind suggests that the domestication of fire occurred before 1,000,000 BC;[22] scholarly consensus indicates that Homo erectus had controlled fire by between 500,000 BC and 400,000 BC.[23][24] Fire, fueled with wood and charcoal, allowed early humans to cook their food to increase its digestibility, improving its nutrient value and broadening the number of foods that could be eaten.[25]
Clothing and shelter
Other technological advances made during the Paleolithic era were clothing and shelter; the adoption of both technologies cannot be dated exactly, but they were a key to humanity's progress. As the Paleolithic era progressed, dwellings became more sophisticated and more elaborate; as early as 380,000 BC, humans were constructing temporary wood huts.[26][27] Clothing, adapted from the fur and hides of hunted animals, helped humanity expand into colder regions; humans began to migrate out of Africa by 200,000 BC and into other continents, such asEurasia.[28]
Humans began to work bones, antler, and hides, as evidenced by burins and racloirs produced during this period.[citation needed]
Neolithic through Classical Antiquity (10,000BC – 300AD)
An array of Neolithic artifacts, including bracelets, axe heads, chisels, and polishing tools.
Man's technological ascent began in earnest in what is known as the Neolithic period ("New stone age"). The invention of polished stone axes was a major advance because it allowed forest clearance on a large scale to create farms. The discovery of agriculture allowed for the feeding of larger populations, and the transition to a sedentist lifestyle increased the number of children that could be simultaneously raised, as young children no longer needed to be carried, as was the case with the nomadic lifestyle. Additionally, children could contribute labor to the raising of crops more readily than they could to the hunter-gatherer lifestyle.[29][30]
With this increase in population and availability of labor came an increase in labor specialization.[31] What triggered the progression from early Neolithic villages to the first cities, such as Uruk, and the first civilizations, such as Sumer, is not specifically known; however, the emergence of increasingly hierarchicalsocial structures, the specialization of labor, trade and war amongst adjacent cultures, and the need for collective action to overcome environmental challenges, such as the building of dikes and reservoirs, are all thought to have played a role.[32]
Metal tools
Continuing improvements led to the furnace and bellows and provided the ability to smelt and forge native metals (naturally occurring in relatively pure form).[33] Gold, copper, silver, and lead, were such early metals. The advantages of copper tools over stone, bone, and wooden tools were quickly apparent to early humans, and native copper was probably used from near the beginning of Neolithic times (about 8000 BC).[34] Native copper does not naturally occur in large amounts, but copper ores are quite common and some of them produce metal easily when burned in wood or charcoal fires. Eventually, the working of metals led to the discovery of alloys such as bronze and brass (about 4000 BC). The first uses of iron alloys such as steel dates to around 1400 BC.
Energy and Transport
Meanwhile, humans were learning to harness other forms of energy. The earliest known use of wind power is the sailboat.[citation needed] The earliest record of a ship under sail is shown on an Egyptian pot dating back to 3200 BC.[citation needed] From prehistoric times, Egyptians probably used "the power of the Nile" annual floods to irrigate their lands, gradually learning to regulate much of it through purposely-built irrigation channels and 'catch' basins. Similarly, the early peoples of Mesopotamia, the Sumerians, learned to use the Tigris and Euphrates rivers for much the same purposes. But more extensive use of wind and water (and even human) power required another invention.
The
wheel was invented in circa 4000 BC.
According to archaeologists, the wheel was invented around 4000 B.C. The wheel was probably independently invented in Mesopotamia (in present-day Iraq) as well. Estimates on when this may have occurred range from 5500 to 3000 B.C., with most experts putting it closer to 4000 B.C. The oldest artifacts with drawings that depict wheeled carts date from about 3000 B.C.; however, the wheel may have been in use for millennia before these drawings were made. There is also evidence from the same period of time that wheels were used for the production of pottery. (Note that the original potter's wheel was probably not a wheel, but rather an irregularly shaped slab of flat wood with a small hollowed or pierced area near the center and mounted on a peg driven into the earth. It would have been rotated by repeated tugs by the potter or his assistant.) More recently, the oldest-known wooden wheel in the world was found in the Ljubljana marshes of Slovenia.[35]
The invention of the wheel revolutionized activities as disparate as transportation, war, and the production of pottery (for which it may have been first used). It didn't take long to discover that wheeled wagons could be used to carry heavy loads and fast (rotary) potters' wheels enabled early mass production of pottery. But it was the use of the wheel as a transformer of energy (through water wheels, windmills, and even treadmills) that revolutionized the application of nonhuman power sources.
Modern history (300 AD —)
Tools include both simple machines (such as the lever, the screw, and the pulley), and more complex machines (such as the clock, the engine, the electric generator and the electric motor, the computer, radio, and the Space Station, among many others). As tools increase in complexity, so does the type of knowledge needed to support them. Complex modern machines require libraries of written technical manuals of collected information that has continually increased and improved — their designers, builders, maintainers, and users often require the mastery of decades of sophisticated general and specific training. Moreover, these tools have become so complex that a comprehensive infrastructure of technical knowledge-based lesser tools, processes and practices (complex tools in themselves) exist to support them, including engineering,medicine, and computer science. Complex manufacturing and construction techniques and organizations are needed to construct and maintain them. Entire industries have arisen to support and develop succeeding generations of increasingly more complex tools. The relationship of technology with society ( culture) is generally characterized as synergistic, symbiotic, co-dependent, co-influential, and co-producing, i.e. technology and society depend heavily one upon the other (technology upon culture, and culture upon technology). It is also generally believed that this synergistic relationship first occurred at the dawn of humankind with the invention of simple tools, and continues with modern technologies today. Today and throughout history, technology influences and is influenced by such societal issues/factors as economics, values, ethics, institutions, groups, the environment, government, among others. The discipline studying the impacts of science, technology, and society and vice versa is called Science and technology in society.
