History

History

Paleolithic (2.5  10 ka)

A primitive chopper

The use of tools by early humans was partly a process of discovery and of evolution. Early humans evolved from a species of foraginghominids which were already bipedal,^[21] with a brain mass approximately one third of modern humans.^[22] Tool use remained relatively unchanged for most of early human history. Approximately 50,000 years ago, the use of tools and complex set of behaviors emerged, believed by many archaeologists to be connected to the emergence of fully modern language.^[23]

Stone tools

Hand axes from the Acheulian period

A Clovis point, made via pressure flaking

Hominids started using primitive stone tools millions of years ago. The earliest stone tools were little more than a fractured rock, but approximately 75,000 years ago,^[24] pressure flaking provided a way to make much finer work.

Fire

Main article: Control of fire by early humans

The discovery and utilization of fire, a simple energy source with many profound uses, was a turning point in the technological evolution of humankind.^[25] 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 Ma;^[26] scholarly consensus indicates that Homo erectus had controlled fire by between 500 and 400 ka.^[27][28] 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.^[29]

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 ka, humans were constructing temporary wood huts.^[30][31] 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 ka and into other continents such as Eurasia.^[32]

Neolithic through classical antiquity (10 ka – 300 CE)

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 that allowed forest clearance on a large scale to create farms. Agriculture fed larger populations, and the transition to sedentism allowed simultaneously raising more children, as infants no longer needed to be carried, as nomadic ones must. Additionally, children could contribute labor to the raising of crops more readily than they could to the hunter-gatherer economy.^[33][34]

With this increase in population and availability of labor came an increase in labor specialization.^[35] 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 hierarchical social structures and specialized labor, of trade and war amongst adjacent cultures, and the need for collective action to overcome environmental challenges such as irrigation, are all thought to have played a role.^[36]

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).^[37] 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 10 ka).^[38] 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 BCE). The first uses of iron alloys such as steel dates to around 1800 BCE.^[39][40]

Energy and transport

The wheel was invented circa 4000 BCE.

Main article: History of transport

Meanwhile, humans were learning to harness other forms of energy. The earliest known use of wind power is the sailboat; the earliest record of a ship under sail is that of a Nile boat that dates back to the 8th millennium BCE.^[41] From prehistoric times, Egyptians probably used the power of the annual flooding of the Nile 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. However, more extensive use of wind and water (and even human) power required another invention.

According to archaeologists, the wheel was invented around 4000 BCE probably independently and nearly simultaneously in Mesopotamia (in present-day Iraq), the Northern Caucasus (Maykop culture) and Central Europe.^[42] Estimates on when this may have occurred range from 5500 to 3000 BCE with most experts putting it closer to 4000 BCE.^[43] The oldest artifacts with drawings that depict wheeled carts date from about 3500 BCE;^[44] however, the wheel may have been in use for millennia before these drawings were made. There is also evidence from the same period for the use of the potter's wheel. More recently, the oldest-known wooden wheel in the world was found in the Ljubljana marshes of Slovenia.^[45]

The invention of the wheel revolutionized trade and war. It did not take long to discover that wheeled wagons could be used to carry heavy loads. 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.