Stone tools, development

Human technology developed from the first stone tools about two and a half million years ago. In the beginning, the rate of development was slow. Hundreds of thousands of years passed without much change. Today, new technologies are reported daily on television and in newspapers. 

Cellulosic materials form the bulk of the readily available natural fuels. The combustion of these materials is closely associated with the development of human culture and its environment. According to Stewart, language, stone tools, and control of fire probably distinguished mankind from other primates by the beginning of the Pleistocene era, about one million years ago. The deposits in the Choukoutien cave, where the skulls and fossilized bones of Peking... 

Human ideas about the matter that makes up the world have developed in conjunction with our ability to transform and manipulate matter. We discovered the elements by trying to understand how we could do more with the material around us. These efforts go back to the very origin of human life. The manipulation of matter has been so important to human life that historians and archeologists have often identified different periods in history by the most advanced material a particular society could produce at a given time. Thus, we have the Paleolithic era, or Stone Age, followed by the Bronze Age and the Iron Age. The oldest stone tools, found in 1997 near the Gona River, in Ethiopia, by the researchers John W. K. Harris and Sileshi Semaw, date from 2.5 to 2.6 million years ago. Stone tools are the primary record of our hominid ancestors attempts to modify the environment. Tool use almost certainly predates this time, but objects made of other materials, such as wood, bone, or horn, have not survived the passing of the ages or cannot be clearly shown to have been tools. 

Because of these problems in understanding the function of stone tools, researchers have developed new methods for learning about how these implements were used. Microwear analysis involves the use of high-powered microscopes to study the magnified edges of stone tools (Fig. 6.8). The breakthrough in microwear studies... 

Approximately 2.6 million years ago (MYA), the hominin speeies that eventnally led to Homo began to inelude more and more animal food in their diet. A nnmber of lines of evidenee snpport this viewpoint. First, Oldowanlithic technology appears in the fossil record 2.6 MYA, and there is clear cut evidence to show that these tools were used to butcher and disarticulate animal carcasses. " " Stone tool cut marks on the bones of prey animals and evidence for marrow extraction appear concurrently in the fossil record with the development of Oldowan lithic technology by at least 2.5 MYA. It is not entirely clear which specific early hominin specie or species manufactured and used these earliest stone tools, however Australopithecus garhi might have been a likely candidate. ... 

A major contribution of SEU is that it represents differing attitudes towards risk and provides a normative model of decision making under uncertainty. The prescriptions of SEU are also clear and testable. Consequently, SEU has played a major role in fields other than economics, both as a tool for improving human decision making and as a stepping stone for developing models that describe how people make decisions when outcomes are uncertain. As discussed further in Section 4, much of this work has been done in psychology. 

Primitiveness only resides in the means that ancient man had to hand the development and refinement of the available technologies was complete. Stone tools, mined in a centralised industry, pre-finished and then distributed across a vast trading area of Europe and Scandinavia, were worked up into beautiful implements with an anthropomorphic quality lost to modern production. 

Cemented tungsten carbides also find use as a support for polycrystalline diamond (PCD) cutting tips, or as a matrix alloy with cobalt, nickel, copper, and iron, ia which diamond particles are embedded. These tools are employed ia a variety of iadustries including mineral exploration and development oil and gas exploration and production and concrete, asphalt, and dimension stone cutting. 

Enzymatic desizing is one of the oldest nonfood appHcations of commercial amylases. Another type of enzyme, microbial ceUulases, has developed within the textile iadustry as a tool for fabric finishing, ia particular for denim garment finishing. CeUulases can achieve the fashionable worn look traditionaUy obtained by the abrasive action of pumice stones, ie, stone-washing. 

More than 10,000 years ago, the first developments in the field of metallurgy were made in the Near East. Until that time man had used tools made of wood, bone and stone and with these materials he was able to meet all his requirements for devices and tools. An example from that period is the knife made of obsidian, a shiny black, brown or grey magmatically formed rock. The material is very finely crystallized owing to rapid cooling and is therefore often called volcanic glass. By beating it with another rock, you can break off extremely sharp pieces, a property shared with the flint that was mined in the south of The Netherlands in prehistoric times (fig.2.1). 

In the earliest stages of human history, people and their homi-nid ancestors relied on easily obtainable natural materials, such as wood, stone, and clay. They developed techniques for fashioning these materials into the weapons, tools, buildings, and household items needed in their everyday lives. The earliest recorded tools date to 3.1 to 2.5 million years ago from the Hadar region of Africa. These tools were made of volcanic rock and were probably used to shape household items, weapons, and other tools. If the earliest humans made and used tools of organic materials, such as skin or rope, they would all have decayed, and no record of them remains today. 

Since ancient times, the development and use of materials has been one of the basic objectives of mankind. Eras, that is, the Stone Age, the Bronze Age, and the Iron Age, have been named after the fundamental material used by mankind to construct their tools. Materials science is the modern activity that provides the raw material for this endless need, demanded by the progress in all fields of industry and technology, of new materials for the development of society. 

In the Stone Age, tools and weapons were carved from stone spearheads, axheads, knives. Early Indians developed remarkable skills in reshaping natural materials. Their clay bowls were made largely of compounds of aluminum, silicon, and oxygen. 

---