Aşıklı Höyük is a settlement mound located nearly 1 km south of Kızılkaya village on the bank of the Melendiz brook, 25 kilometers southeast of Aksaray, Turkey. Aşıklı Höyük is located in an area covered by the volcanic tuff of central Cappadocia, in Aksaray Province; the archaeological site of Aşıklı Höyük was first settled in the Aceramic Neolithic period, around 9000 B. C, it is situated 1119.5 metres above sea level, a little higher than the region's average of c. 1000 metres. The site itself is about 4 ha smaller than the situated site of Çatalhöyük; the surrounding landscape is formed by erosion of river valleys into tuff deposits. The Melendiz Valley, where the Aşıklı Höyük is located, constitutes a favourable and diverse habitat; the proximity to an obsidian source did become the base of a trade with the material supplying areas as far away as today's Cyprus and Iraq. Aşıklı Höyük was first investigated by Professor Ian A. Todd when he visited the site in the summer of 1964. Todd emphasised the importance of the obsidian in the area, based on over 6000 obsidian pieces collected from the surface layer alone.
The site was classified as a medium sized mound and destroyed by the river situated next to it. On the basis of the lithics and animal bones located in the surface layers the site became known as a contemporary to the Palestine PPNB, reinforced by 14C dates; the first comprehensive excavations took place late: first when the government launched a plan that would result in the rise of the waters of the Mamasın Lake located close to Aşıklı Höyük, Professor Ufuk Esin started the salvage excavations in 1989. Nine excavations have been undertaken up to 2003, uncovering 4200 m2 on the horizontal plain, making it one of the largest scale excavations in the region; the newest dates for Aşıklı Höyük show that the occupational period was from 8200 to 7400 BC, extracted from 3 layers with a total of 13 phases. It is known as one of the earliest Aceramic Neolithic sites on the Anatolian plateau, the prior mentioned extraction of the obsidian source was to be frequented as far back as the Paleolithic nomadic hunter-gatherers.
Due to its date and structural organization Aşıklı Höyük is known to be "a prime example of a first foray into sedentism". After more than 400 rooms had been excavated, the total number of individual found to have been buried within the settlement did not surpass 70. All these burials were under building floors; the dead were placed in pits cut through the floor during the occupation of the building. The buried are people of all ages. There is a variety of skeletal body postures, from burials in a hocker position to extended skeletons facing upwards. Others are lying on one side with the legs bent at the knees; the orientation of the burials varies within the buildings, as does the number of individuals buried inside them. The male population had individuals up to the age of 55–57 years of age, while the majority of females died between the ages of 20 and 25; the skeletal remains of these women show spinal deformities indicating that they had to carry heavy loads. This does not itself prove; the fact that the men seem to have outlived the women might be interpreted as sign that the women were subject to more strenuous physical labour than their male counterparts.
From Natufian Abu Hureyra there are similar osteological signs, such as pathologies in metatarsals, phalanges and shoulder joints, being specific to females resulting from habitual kneeling in the use of saddle querns. The Neolithic evidence show indications of increased physical workload in the osteological material on both genders, where the male skeletons show signs of joint disease and trauma arguably caused by cutting timber and tilling. Children represent 37.8% of the deceased, with 43.7% mortality within a year of birth. The skeletal remains are complete and with articulations intact, indicating that the burials have been primary; the graves contain either double burials. On one occasion two graves were found under the floor of room AB, belonging to an adjacent court with a large domed mudbrick oven paved with blocks of basalt. In one of the graves were the skeletons of a young woman and an elderly man; the young woman had undergone trepanation and survived only a few days after the operation.
All skeletons were buried in the hocker position, a fetal-like positioning were the arms are embracing the lower limbs. From a different grave a woman shows signs of being scalped after her death, according to the cut marks on her skull; as many as 55% of the skeletons show signs of being burned. The burial under the floor AB is accommodated by walls with the interior side were painted in a purplish red colour; the oven in HG indicates that this was indeed "special individuals of an elite class", claiming it can be compared to the "Terrazzo" Building at Çayönü and the "Temple" Building at Nevalı Çori and therefore have been a shrine used for religious ceremonies. Many of the burials contain burial goods consisting of necklaces and bracelets made of beads of various sorts.70 burials in over 400 rooms suggest that some form of selection took place of, buried at the site, implementing that AB indeed could be the residence or resting place of people influential in terms of both economy and political power.
Rooms containing hearths are more to contain burials. It has been argued that the number of burials could be an
Human prehistory is the period between the use of the first stone tools c. 3.3 million years ago by hominins and the invention of writing systems. The earliest writing systems appeared c. 5,300 years ago, but it took thousands of years for writing to be adopted, it was not used in some human cultures until the 19th century or until the present. The end of prehistory therefore came at different dates in different places, the term is less used in discussing societies where prehistory ended recently. Sumer in Mesopotamia, the Indus valley civilization, ancient Egypt were the first civilizations to develop their own scripts and to keep historical records. Neighboring civilizations were the first to follow. Most other civilizations reached the end of prehistory during the Iron Age; the three-age system of division of prehistory into the Stone Age, followed by the Bronze Age and Iron Age, remains in use for much of Eurasia and North Africa, but is not used in those parts of the world where the working of hard metals arrived abruptly with contact with Eurasian cultures, such as the Americas, Oceania and much of Sub-Saharan Africa.
These areas with some exceptions in Pre-Columbian civilizations in the Americas, did not develop complex writing systems before the arrival of Eurasians, their prehistory reaches into recent periods. The period when a culture is written about by others, but has not developed its own writing is known as the protohistory of the culture. By definition, there are no written records from human prehistory, so dating of prehistoric materials is crucial. Clear techniques for dating were not well-developed until the 19th century; this article is concerned with human prehistory, the time since behaviorally and anatomically modern humans first appeared until the beginning of recorded history. Earlier periods are called "prehistoric". Beginning The term "prehistory" can refer to the vast span of time since the beginning of the Universe or the Earth, but more it refers to the period since life appeared on Earth, or more to the time since human-like beings appeared. End The date marking the end of prehistory is defined as the advent of the contemporary written historical record.
The date varies from region to region depending on the date when relevant records become a useful academic resource. For example, in Egypt it is accepted that prehistory ended around 3200 BCE, whereas in New Guinea the end of the prehistoric era is set much more at around 1900 common era. In Europe the well-documented classical cultures of Ancient Greece and Ancient Rome had neighbouring cultures, including the Celts and to a lesser extent the Etruscans, with little or no writing, historians must decide how much weight to give to the highly prejudiced accounts of these "prehistoric" cultures in Greek and Roman literature. Time periods In dividing up human prehistory in Eurasia, historians use the three-age system, whereas scholars of pre-human time periods use the well-defined geologic record and its internationally defined stratum base within the geologic time scale; the three-age system is the periodization of human prehistory into three consecutive time periods, named for their respective predominant tool-making technologies: Stone Age Bronze Age Iron Age The notion of "prehistory" began to surface during the Enlightenment in the work of antiquarians who used the word'primitive' to describe societies that existed before written records.
The first use of the word prehistory in English, occurred in the Foreign Quarterly Review in 1836. The use of the geologic time scale for pre-human time periods, of the three-age system for human prehistory, is a system that emerged during the late nineteenth century in the work of British and Scandinavian archeologists and anthropologists; the main source for prehistory is archaeology, but some scholars are beginning to make more use of evidence from the natural and social sciences. This view has been articulated by advocates of deep history; the primary researchers into human prehistory are archaeologists and physical anthropologists who use excavation and geographic surveys, other scientific analysis to reveal and interpret the nature and behavior of pre-literate and non-literate peoples. Human population geneticists and historical linguists are providing valuable insight for these questions. Cultural anthropologists help provide context for societal interactions, by which objects of human origin pass among people, allowing an analysis of any article that arises in a human prehistoric context.
Therefore, data about prehistory is provided by a wide variety of natural and social sciences, such as paleontology, archaeology, geology, comparative linguistics, molecular genetics and many others. Human prehistory differs from history not only in terms of its chronology but in the way it deals with the activities of archaeological cultures rather than named nations or individuals. Restricted to material processes and artifacts rather than written records, prehistory is anonymous; because of this, reference terms that prehistorians use, such as Neanderthal or Iron Age are modern labels with definitions sometimes subject to debate. The concept of a "Stone Age" is found useful in the archaeology of most of the world, though in the archaeology of the Americas it is called by different names and begins with a Lithic sta
The Neolithic, the final division of the Stone Age, began about 12,000 years ago when the first development of farming appeared in the Epipalaeolithic Near East, in other parts of the world. The division lasted until the transitional period of the Chalcolithic from about 6,500 years ago, marked by the development of metallurgy, leading up to the Bronze Age and Iron Age. In Northern Europe, the Neolithic lasted until about 1700 BC, while in China it extended until 1200 BC. Other parts of the world remained broadly in the Neolithic stage of development, although this term may not be used, until European contact; the Neolithic comprises a progression of behavioral and cultural characteristics and changes, including the use of wild and domestic crops and of domesticated animals. The term Neolithic derives from the Greek νέος néos, "new" and λίθος líthos, "stone" meaning "New Stone Age"; the term was coined by Sir John Lubbock in 1865 as a refinement of the three-age system. Following the ASPRO chronology, the Neolithic started in around 10,200 BC in the Levant, arising from the Natufian culture, when pioneering use of wild cereals evolved into early farming.
The Natufian period or "proto-Neolithic" lasted from 12,500 to 9,500 BC, is taken to overlap with the Pre-Pottery Neolithic of 10,200–8800 BC. As the Natufians had become dependent on wild cereals in their diet, a sedentary way of life had begun among them, the climatic changes associated with the Younger Dryas are thought to have forced people to develop farming. By 10,200–8800 BC farming communities had arisen in the Levant and spread to Asia Minor, North Africa and North Mesopotamia. Mesopotamia is the site of the earliest developments of the Neolithic Revolution from around 10,000 BC. Early Neolithic farming was limited to a narrow range of plants, both wild and domesticated, which included einkorn wheat and spelt, the keeping of dogs and goats. By about 6900–6400 BC, it included domesticated cattle and pigs, the establishment of permanently or seasonally inhabited settlements, the use of pottery. Not all of these cultural elements characteristic of the Neolithic appeared everywhere in the same order: the earliest farming societies in the Near East did not use pottery.
In other parts of the world, such as Africa, South Asia and Southeast Asia, independent domestication events led to their own regionally distinctive Neolithic cultures, which arose independently of those in Europe and Southwest Asia. Early Japanese societies and other East Asian cultures used pottery before developing agriculture. In the Middle East, cultures identified as Neolithic began appearing in the 10th millennium BC. Early development occurred from there spread eastwards and westwards. Neolithic cultures are attested in southeastern Anatolia and northern Mesopotamia by around 8000 BC; the prehistoric Beifudi site near Yixian in Hebei Province, contains relics of a culture contemporaneous with the Cishan and Xinglongwa cultures of about 6000–5000 BC, neolithic cultures east of the Taihang Mountains, filling in an archaeological gap between the two Northern Chinese cultures. The total excavated area is more than 1,200 square yards, the collection of neolithic findings at the site encompasses two phases.
The Neolithic 1 period began around 10,000 BC in the Levant. A temple area in southeastern Turkey at Göbekli Tepe, dated to around 9500 BC, may be regarded as the beginning of the period; this site was developed by nomadic hunter-gatherer tribes, as evidenced by the lack of permanent housing in the vicinity, may be the oldest known human-made place of worship. At least seven stone circles, covering 25 acres, contain limestone pillars carved with animals and birds. Stone tools were used by as many as hundreds of people to create the pillars, which might have supported roofs. Other early PPNA sites dating to around 9500–9000 BC have been found in Jericho, West Bank, Gilgal in the Jordan Valley, Byblos, Lebanon; the start of Neolithic 1 overlaps the Heavy Neolithic periods to some degree. The major advance of Neolithic 1 was true farming. In the proto-Neolithic Natufian cultures, wild cereals were harvested, early seed selection and re-seeding occurred; the grain was ground into flour. Emmer wheat was domesticated, animals were herded and domesticated.
In 2006, remains of figs were discovered in a house in Jericho dated to 9400 BC. The figs are of a mutant variety that cannot be pollinated by insects, therefore the trees can only reproduce from cuttings; this evidence suggests that figs were the first cultivated crop and mark the invention of the technology of farming. This occurred centuries before the first cultivation of grains. Settlements became more permanent, with circular houses, much like those of the Natufians, with single rooms. However, these houses were for the first time made of mudbrick; the settlement had a surrounding stone wall and a stone tower. The wall served as protection from nearby groups, as protection from floods, or to keep animals penned; some of the enclosures suggest grain and meat storage. The Neolithic 2 began around 8800 BC according to the ASPRO chronology in the Levant; as with the PPNA dates, there are two versions from the same laboratories noted above. This system of terminology, however, is not convenient for southeast Anatolia and settlements of the middle Anatolia basin.
A settlement of 3,000 inhabitants was found in th
History of technology
The history of technology is the history of the invention of tools and techniques and is one of the categories of the history of humanity. Technology can refer to methods ranging from as simple as stone tools to the complex genetic engineering and information technology that has emerged since the 1980s; the term technology comes from the Greek word techne, meaning art and craft, the word logos, meaning word and speech. It was first used to describe applied arts, but it is now used to described advancements and changes which affect the environment around us. New knowledge has enabled people to create new things, conversely, many scientific endeavors are made possible by technologies which assist humans in traveling to places they could not reach, by scientific instruments by which we study nature in more detail than our natural senses allow. Since much of technology is applied science, technical history is connected to the history of science. Since technology uses resources, technical history is connected to economic history.
From those resources, technology produces other resources, including technological artifacts used in everyday life. Technological change affects and is affected by, a society's cultural traditions, it is a force for economic growth and a means to develop and project economic, military power and wealth. Many sociologists and anthropologists have created social theories dealing with social and cultural evolution. Some, like Lewis H. Morgan, Leslie White, Gerhard Lenski have declared technological progress to be the primary factor driving the development of human civilization. Morgan's concept of three major stages of social evolution can be divided by technological milestones, such as fire. White argued. For White, "the primary function of culture" is to "harness and control energy." White differentiates between five stages of human development: In the first, people use the energy of their own muscles. In the second, they use the energy of domesticated animals. In the third, they use the energy of plants.
In the fourth, they learn to use the energy of natural resources: coal, gas. In the fifth, they harness nuclear energy. White introduced a formula P=E*T, where E is a measure of energy consumed, T is the measure of the efficiency of technical factors using the energy. In his own words, "culture evolves as the amount of energy harnessed per capita per year is increased, or as the efficiency of the instrumental means of putting the energy to work is increased". Nikolai Kardashev extrapolated his theory, creating the Kardashev scale, which categorizes the energy use of advanced civilizations. Lenski's approach focuses on information; the more information and knowledge a given society has, the more advanced. He identifies four stages of human development, based on advances in the history of communication. In the first stage, information is passed by genes. In the second, when humans gain sentience, they can pass information through experience. In the third, the humans start develop logic. In the fourth, they can develop language and writing.
Advancements in communications technology translate into advancements in the economic system and political system, distribution of wealth, social inequality and other spheres of social life. He differentiates societies based on their level of technology and economy: hunter-gatherer, simple agricultural, advanced agricultural, special. In economics, productivity is a measure of technological progress. Productivity increases. Another indicator of technological progress is the development of new products and services, necessary to offset unemployment that would otherwise result as labor inputs are reduced. In developed countries productivity growth has been slowing since the late 1970s. For example, employment in manufacturing in the United States declined from over 30% in the 1940s to just over 10% 70 years later. Similar changes occurred in other developed countries; this stage is referred to as post-industrial. In the late 1970s sociologists and anthropologists like Alvin Toffler, Daniel Bell and John Naisbitt have approached the theories of post-industrial societies, arguing that the current era of industrial society is coming to an end, services and information are becoming more important than industry and goods.
Some extreme visions of the post-industrial society in fiction, are strikingly similar to the visions of near and post-Singularity societies. The following is a summary of the history of technology by time period and geography: During most of the Paleolithic – the bulk of the Stone Age – all humans had a lifestyle which involved limited tools and few permanent settlements; the first major technologies were tied to survival and food preparation. Stone tools and weapons and clothing were technological developments of major importance during this period. Human ancestors have been using stone and other tools since long before the emergence of Homo sapiens 200,000 years ago; the earliest methods of stone tool making, known as the Oldowan "industry", date back to at least 2.3 million years ago, with the earliest direct evidence of tool usage found in Ethiopia within the Great Rift Valley, dating back to 2.5 million years ago. This era of stone tool use is called the Paleolithic
Burke Museum of Natural History and Culture
The Burke Museum of Natural History and Culture is a natural history museum in Seattle, Washington, in the United States. Established in 1899 as the Washington State Museum, it traces its origins to a high school naturalist club formed in 1879; the museum is the oldest in Washington state and boasts a collection of more than 16 million artifacts, including the world's largest collection of spread bird wings. Located on the campus of the University of Washington, the Burke Museum is the official state museum of Washington; the roots of the Burke Museum can be traced to a natural history club formed by high school students in the 19th century. The group was formed in December 1879 by students Edmond S. Meany, J. O. Young, P. Brooks Randolph, Charles Denny. Denny's father, city founder Arthur Denny, was a regent of the Territorial University of Washington and arranged for the group to meet on campus; the Young Naturalists adopted a constitution and bylaws, the official name "Young Naturalists Society," in 1880.
As the founding members graduated high school and matriculated to the university, the membership of the Young Naturalists expanded to include university students. In 1882 Orson "Bug" Johnson was retained as a biology instructor at the University of Washington, bringing 20,000 animal specimens with him. Johnson involved himself with the Young Naturalists, the addition of his collection gave the club the largest natural history collection in the Pacific Northwest. Under Johnson's direction, the Young Naturalists began expanding this nucleus of specimens and artifacts, which were stored in a backroom of the Denny home. A permanent structure to house the growing collection was built on the Territorial University's campus in 1886, with the club soliciting donations to fund its construction. Many specimens in the collection were borrowed by university faculty to assist in instruction. In the 1890s Edmond Meany returned to teach history at the university, he led a revitalization of the group that he had helped found a decade before, bringing in new members, including women.
By this point the society's collection had grown to include more than 60,000 specimens. The University of Washington moved its campus from downtown Seattle to its present location in 1895; the portion of the Young Naturalists collection, used in university instruction was relocated to the university's Denny Hall while the remainder stayed in the Young Naturalists clubhouse downtown. In 1899 the Washington State Legislature designated the portion of Denny Hall used to house the collection as the Washington State Museum. In 1904 the Young Naturalists voted to donate the rest of their collection to the Washington State Museum and disband; the 1909 Alaska–Yukon–Pacific Exposition brought a boon of construction to the University of Washington's campus. When the fair ended, the Washington State Museum moved into its first dedicated building, the fair's former California Building. Persistent leaks in that facility caused it to relocate to the fair's former Forestry Building which, it was soon discovered, was infested with bark beetles.
For four years, from 1923 to 1927, the museum's collections were disbursed around campus. The situation was resolved in 1927 when the museum moved into what had been constructed as the Washington State Building for the AYP Expo. In 1929, Erna Gunther became a post she would hold for more than 25 years; the museum found itself, once again, displaced in 1957 after its AYP Expo-era building was condemned. When Thomas Burke died in 1925, his wife, Caroline McGilvra Burke, sought an appropriate monument for her husband that would "advance the cause of a better mutual understanding between... the people of the Pacific shores." A collector of Native American artifacts herself, she bequeathed her personal collection to the museum following her death in 1932. The Burke estate offered to help fund a new state museum, with one major stipulation - the structure had to be named after Burke; some University officials balked at this. The institution had been known as the Washington State Museum since 1899, the Burke funds would only go toward a third of the construction costs.
Other funds came from a National Science Foundation grant, but the new building was still smaller than one that Erna Gunther recommended. The new facility was dedicated on May 3, 1964, with its new director, Walter A. Fairservis, at the helm. In 1996, the museum launched a ten-year plan to move its exhibition space off campus and into a downtown Seattle location. Under the proposal and preservationists would continue to work at the University of Washington while exhibits would be hosted at a new site; the proposal did not materialize. In 2014, the museum made another push for a new facility, asking the Washington State Legislature for half the $95 million needed to construct a 110,000 square-foot facility to replace its current building; the new Burke Museum building finished construction in 2018, the old building closed at the end of the year to transfer the collection's 16 million items before its demolition in April 2019. The new museum will open in fall 2019; the museum houses more than 16 million artifacts and specimens in its anthropology and geology research divisions.
According to the museum, its ornithology division includes the largest collection of spread bird wings in the world, while the museum's collection of frozen bird tissues is the world's second largest. The museum states that its collection of Northwest Coast ethnographic material is the fifth largest collection of Native American art in the world, numbering 10,000 objects, among which are "the important early Swan, Eells and Waters collections, as well as
A hand axe is a prehistoric stone tool with two faces, the longest-used tool in human history. It is made from flint or chert, it is characteristic of middle Palaeolithic periods. Its technical name comes from the fact that the archetypical model is bifacial Lithic flake and almond-shaped. Hand axes tend to be symmetrical along their longitudinal axis and formed by percussion; the most common hand axes have a pointed end and rounded base, which gives them their characteristic shape, both faces have been knapped to remove the natural cortex, at least partially. Hand axes are a type of the somewhat wider biface group of two-faced weapons. Hand axes were the first prehistoric tools to be recognized as such: the first published representation of a hand axe was drawn by John Frere and appeared in a British publication in 1800; until that time, their origins were thought to be supernatural. They were called thunderstones, because popular tradition held that they had fallen from the sky during storms or were formed inside the earth by a lightning strike and appeared at the surface.
They are used in some rural areas as an amulet to protect against storms. Hand axe tools were used to butcher animals. Four classes of hand axe are: 1: Large, thick hand axes reduced from cores or thick flakes, referred to as blanks 2: Thinned blanks. While form remains rough and uncertain, an effort has been made to reduce the thickness of the flake or core 3: Either a preform or crude formalized tool, such as an adze 4: Finer formalized tool types such as projectile points and fine bifacesWhile Class 4 hand axes are referred to as "formalized tools", bifaces from any stage of a lithic reduction sequence may be used as tools.. French antiquarian André Vayson de Pradenne introduced the word biface in 1920; this term co-exists with the more popular hand axe, coined by Louis Laurent Gabriel de Mortillet much earlier, The continued use of the word biface by François Bordes and Lionel Balout supported its use in France and Spain, where it replaced the term hand axe. Use of the expression hand axe has continued in English as the equivalent of the French biface, while biface applies more for any piece, carved on both sides by the removal of shallow or deep flakes.
The expression faustkeil is used in German. It can be translated as hand axe, although in a stricter sense it means "fist wedge", it is the same in Dutch where the expression used is vuistbijl which means "fist axe". The same locution occurs in other languages. However, the general impression of these tools were based on ideal pieces that were of such perfect shape that they caught the attention of non-experts, their typology broadened the term's meaning. Biface hand axe and bifacial lithic items are distinguished. A hand axe need not be a bifacial item and many bifacial items are not hand axes. Nor were hand axes and bifacial items exclusive to the Lower Palaeolithic period in the Old World, they appear throughout the world and in many different pre-historical epochs, without implying an ancient origin. Lithic typology was abandoned as a dating system. Examples of this include the "quasi-bifaces" that sometimes appear in strata from the Gravettian and Magdalenian periods in France and Spain, the crude bifacial pieces of the Lupemban culture or the pyriform tools found near Sagua La Grande in Cuba.
The word biface refers to something different in English than biface in French or bifaz in Spanish, which could lead to many misunderstandings. Bifacially carved cutting tools, similar to hand axes, were used to clear scrub vegetation throughout the Neolithic and Chalcolithic periods; these tools were a cheaper alternative to polished axes. The modern day villages along the Sepik river in New Guinea continue to use tools that are identical to hand axes to clear forest. "The term biface should be reserved for items from before the Würm II-III interstadial", although certain objects could exceptionally be called bifaces. Hand axe does not relate to axe, overused in lithic typology to describe a wide variety of stone tools. At the time the use of such items was not understood. In the particular case of Palaeolithic hand axes the term axe is an inadequate description. Lionel Balout stated, "the term should be rejected as an erroneous interpretation of these objects that are not'axes'". Subsequent studies supported this idea those examining the signs of use.
Hand axes are made of flint, but rhyolites, phonolites and other coarse rocks were used as well. Obsidian, natural volcanic glass and was used. Most hand axes have a sharp border all around, No academic consensus describes their use; the pioneers of Palaeolithic tool studies first suggested that bifaces were used as axes or at least for use in demanding physical activities. Other uses showed; the different forms and shapes of known specimens led them to be described as the Acheulean "Swiss Army knife". Each type of tool could have been used for multiple tasks. Wells proposed in 1899 that hand axes were used as missile weapons to hunt prey – an interpretation supported by Calvin, who suggested that some of the rounder specimens of Acheulean hand axes were used as hunting projectiles or as "killer frisbees" meant to be thrown at a herd of animals at a w
In archaeology, in particular of the Stone Age, lithic reduction is the process of fashioning stones or rocks from their natural state into tools or weapons by removing some parts. It has been intensely studied and many archaeological industries are identified entirely by the lithic analysis of the precise style of their tools and the chaîne opératoire of the reduction techniques they used; the starting point is the selection of a piece of tool stone, detached by natural geological processes, is an appropriate size and shape. In some cases solid rock or larger boulders may be quarried and broken into suitable smaller pieces, in others the starting point may be a piece of the debitage, a flake removed from a previous operation to make a larger tool; the selected piece is called the lithic core. A basic distinction is that between flaked or chipped stone, the main subject here, ground stone objects made by grinding. Flaked stone reduction involves the use of a hard hammer percussor, such as a hammerstone, a soft hammer fabricator, or a wood or antler punch to detach lithic flakes from the lithic core.
As flakes are detached in sequence, the original mass of stone is reduced. Lithic reduction may be performed in order to obtain sharp flakes, of which a variety of tools can be made, or to rough out a blank for refinement into a projectile point, knife, or other object. Flakes of regular size that are at least twice as long as they are broad are called blades. Lithic tools produced this way may be unifacial. Cryptocrystalline or amorphous stone such as chert, flint and chalcedony, as well as other fine-grained stone material, such as rhyolite and quartzite, were used as a source material for producing stone tools; as these materials lack natural planes of separation, conchoidal fractures occur when they are struck with sufficient force. The propagation of force through the material takes the form of a Hertzian cone that originates from the point of impact and results in the separation of material from the objective piece in the form of a partial cone known as a lithic flake; this process is predictable, allows the flintknapper to control and direct the application of force so as to shape the material being worked.
Controlled experiments may be performed using glass cores and consistent applied force in order to determine how varying factors affect core reduction. It has been shown that stages in the lithic reduction sequence may be misleading and that a better way to assess the data is by looking at it as a continuum; the assumptions that archaeologists sometimes make regarding the reduction sequence based on the placement of a flake into a stage can be unfounded. For example, a significant amount of cortex can be present on a flake taken off near the end of the reduction sequence. Removed flakes exhibit features characteristic of conchoidal fracturing, including striking platforms, bulbs of force, eraillures. Flakes are quite sharp, with distal edges only a few molecules thick when they have a feather termination; these flakes can be used directly as tools or modified into other utilitarian implements, such as spokeshaves and scrapers. By understanding the complex processes of lithic reduction, archaeologists recognize that the pattern and amount of reduction contribute tremendous effect to lithic assemblage compositions.
One of the measurements is the geometric index of reduction. There are two elements in this index:'t' and'T'. The'T' is the'height' of maximum blank thickness and the't' is the height of retouched scar from the ventral surface; the ratio between t and T is the geometric index of reduction. In theory this ratio shall range between 0 and 1; the bigger the number is the larger amount of lost weight from lithic flake. By using a logarithmic scale, a linear relationship between the geometric index and the percentage of original flake weight lost through retouch is confirmed. In choosing a reduction index, it is important to understand the strengths and weaknesses of each method, how they fit to the intended research question, as different indices provide different levels of information. For example, Kuhn's geometric index of unifacial reduction, which describes the ratio of scar height relative to the flake thickness, is influenced by the morphology of the flake blank which limits the applicability of this reduction index.
Alongside the various percussion and manipulation techniques described below, there is evidence that heat was at least sometimes used. Experimental archaeology has demonstrated that heated stones are sometimes much easier to flake, with larger flakes being produced in flint, for example. In some cases the heating changes the colour of the stone. Percussion reduction, or percussion flaking, refers to removal of flakes by impact. A core or other objective piece, such as a formed tool, is held in one hand, struck with a hammer or percussor. Alternatively, the objective piece can be struck between a stationary anvil-stone, known as bipolar percussion. Percussion can be done by throwing the objective piece at an anvil stone; this is sometimes called projectile percussion. Percussors are traditionally either a stone cobble or pebble referred to as a hammerstone, or a billet made of bone, antler, or wood. Flakes are struck from a core using a punch, in which case the percussor never makes contact with the objective piece.
This technique is referred to