Archaeological Dating Methods (2)

Absolute Dating

Absolute dating assigns fixed dates to the age of an object, people or intangible concepts, such as human language development.It means absolute dating methods produce specific chronological dates for objects and occupations. Absolute dating largely relies on scientific developments of the 20th century, but it also can derive absolute dates from history and archaeology.These dating methods provides a computed numerical age in contrast with relative dating which provides only an order of events.In archeology, absolute dating is usually based on the physical or chemical properties of the materials of artifacts, buildings, or other items that have been modified by humans.This type of dating employs many dating techniques* like atomic clocks, carbon dating, annual cycle methods, and trapped electron method. 

*After 1950, the physical sciences contributed a number of absolute dating techniques that had a revolutionary effect on archaeology and geology. These techniques are based upon the measurement of radioactive processes (radiocarbon; potassium-argon, uranium-lead, thorium-lead, etc.; fission track; thermoluminescence; optically stimulated luminescence; and electron-spin resonance), chemical processes (amino-acid racemization and obsidian hydration), and the magnetic properties of igneous material, baked clay, and sedimentary deposits (paleomagnetism). Other techniques are occasionally useful, for example, historical or iconographic references to datable astronomical events such as solar eclipses (archaeoastronomy).

Prior to the discovery of radiometric dating which provided a means of absolute dating in the early 20th century, archaeologists and geologists were largely limited to the use of relative dating techniques to determine the age of geological events.Though relative dating can only determine the sequential order in which a series of events occurred, not when they occur, it remains a useful technique especially in materials lacking radioactive isotopes.The Law of Superposition was the summary outcome of 'relative dating' as observed in geology from the 17th century to the early 20th century.

The most popular method of radio dating is radiocarbon dating which is possible because of the presence of C-14, an unstable isotope of carbon. C-14 has a half life of 5730 years which means that only half of the original amount is left in the fossil after 5730 years while half of the remaining amount is left after another 5730 years. This gives away the true age of the fossil that contains C-14 that starts decaying after the death of the human being or animal. Dendrochronology is another of the popular method of finding the exact age through growth and patterns of thick and thin ring formation in fossil trees. It is clear then that absolute dating is based upon physical and chemical properties of artifacts that provide a clue regarding the true age. 

The absolute dating methods most widely used and accepted are based on the natural radioactivity of certain minerals found in rocks. Since the rate of radioactive decay of any particular isotope is known, the age of a specimen can be computed from the relative proportions of the remaining radioactive material and its decay products. By this method the age of the earth is estimated to be about 4.5 billion years old. Some of the radioactive elements used in dating and their decay products (their stable daughter isotopes) are uranium-238 to lead-206, uranium-235 to lead-207, thorium-232 to lead-208, samarium-147 to neodymium-143, rubidium-87 to strontium-87, and potassium-40 to argon-40. Each radioactive member of these series has a known, constant decay rate, measured by its half-life, that is unaffected by any physical or chemical changes. Each decay element has an effective age range, including uranium-238 (100 million to 4.5 billion years) and potassium-40 (100,000 to 4.5 billion years).

Radiometric dating - Principles and History 

In 1896, French physicist Henri Becquerel discovered radioactivity: the spontaneous emission of particles and energy from unstable nuclei of elements.The atoms of some chemical elements have different forms, called isotopes. These break down over time in a process scientists call radioactive decay. Each original isotope, called the parent, gradually decays to form a new isotope, called the daughter. Each isotope is identified with what is called a ‘mass number’. When ‘parent’ uranium-238 decays, for example, it produces subatomic particles, energy and ‘daughter’ lead-206.

Isotope:  A version of an atom that differs from other atoms of the same element only in the number of neutrons.  Different isotopes of an element have similar chemical properties (undergo similar chemical reactions) but have different physical properties (such as evaporation rates).

Stable Isotope:  An isotope that persists forever because it has a “stable” ratio of protons to neutrons.  For example, carbon-12 is a stable isotope.

Radioactive (or unstable) Isotope:  An isotope that decays into another element because it has an “unstable” ratio of protons to neutrons.  For example, carbon-14 is a radioactive isotope.

During radioactive decay, the radioactive parent isotope changes to a stable daughter isotope giving off heat in the process.  There are 3 types of radioactive emissions:

Alpha ray: Equivalent to two protons and two neutrons (essentially a helium nucleus).

Beta ray: A free electron is released when a neutron converts to a proton.

Gamma ray: Consists of a photon (a packet of energy).

Some radioactive parent isotopes decay directly to a daughter isotope.  However, some radioactive atoms decay to the daughter atom through a series of intermediate steps (called a decay series).  The U238 decay series is a good example.The half-life is the amount of time required for one half of the parent to decay to daughter.Initially, there are many radioactive parent atoms so there are more radioactive emissions.  As decay proceeds and there are fewer parent atoms and fewer emissions.  By the 1st half life, 50% of the parent atoms will have decayed to daughter.  By the 2nd half life, another 50% of the remaining parent will have decayed (leaving 25% parent and 75% daughter).

Absolute age dating is based upon the decay of radioactive (unstable) isotopes.Since the decay rate is constant over time, the parent:daughter ratio can be used to calculate the age of the mineral or rock.

Dating basically depends upon 3 measurements:

1) the amount of unstable parent isotope in the mineral

2) the amount of stable daughter isotope in the mineral

3) the decay constant (l) of the particular radioactive parent isotope.

Radiometric dating (also called radioactive dating) is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates (In radiometry, the rate of radioactive decay of a specific element provides an absolute date).The use of radiometric dating was first published in 1907 by Bertram Boltwood and is now the principal source of information about the absolute age of rocks and other geological features, including the age of the Earth itself, and can be used to date a wide range of natural and man-made materials. Together with stratigraphic principles, radiometric dating methods are used in geochronology to establish the geological time scale.Among the best-known techniques are radiocarbon dating, potassium-argon dating and uranium-lead dating.

Radiocarbon dating measures radioactive isotopes in once-living organic material instead of rock, using the decay of carbon-14 to nitrogen-14 .Carbon-14 dating is probably one of the best-known dating methods, but the half-life of Carbon-14 is approximately 5730 years, plus or minus 40 years. Because of the fairly fast decay rate of carbon-14, it can only be used on material up to about 60,000 years old. Geologists use radiocarbon to date such materials as wood and pollen trapped in sediment, which indicates the date of the sediment itself. 

The atmospheric C 14 is incorporated into carbon dioxide molecules (CO2).  Organisms acquire C 14 from the air and water (along with 13C and 12C), and they acquire the environmental ratios of these isotopes.  However, when organisms die, they stop acquiring any carbon and the C 14starts to decay back to N 14 via beta decay.  The C 14 :N 14 ratio decreases over time, and this ratio can be used to calculate a material's age.All organic matter (bones, shells, wood, charcoal, cloth, and limestone) contains C-14and can be dated with this technique.

Carbon-14 has a relatively short half life of 5,730 years.  It is good for dating young rocks and artifacts.  Beyond 60,000 - 80,000 years, there is too little Carbon-14 left in the sample and this technique cannot be used.

Potassium-argon dating is another absolute dating method that is used to determine the age of igneous or sedimentary rocks. This, in turn, should provide some evidence for the dates of the fossils within the rocks. In this method, an absolute date is determined by measuring the amount of decay of potassium-40, a radioactive isotope of the element potassium that has transformed into the stable isotope argon-40.Potassium-40, for example, decays into Argon-40 with a half-life of 1.25 billion years, so that after 1.25 billion years half of the Potassium-40 in a rock will have become Argon-40. This means that if a rock sample contained equal amounts of Potassium-40 and Argon-40, it would be 1.25 billion years old.

Fission-track dating is a more recent application of the decay of radioisotopes, but this technique does not use the ratio of parent to daughter isotope to obtain an age.

Most U 238 undergoes alpha decay.  However, a very small proportion of U 238 nuclei undergo fission and the nucleus splits to form two smaller but very energetic nuclei that move away from each other.  When this happens in a mineral, the two departing nuclei leave behind a trail of destruction in the crystal lattice.  The trail is called a fission track.

The density of fission tracks in a mineral increase with age and can be used to calculate the mineral's age.

Fission track dating is ideal for samples from “recent” times back to 100,000,000 years.  Beyond 100,000,000 years, the density of the tracks becomes so great (saturated) that they cannot be counted reliably.

Fission tracks can “anneal” or heal with reheating, and so this method is affected by metamorphism.

Note : 

Measuring isotopes is particularly useful for dating igneous and some metamorphic rock, but not sedimentary rock. Sedimentary rock is made of particles derived from other rocks, so measuring isotopes would date the original rock material, not the sediments they have ended up in. However, there are radiometric dating methods that can be used on sedimentary rock, including luminescence dating.

All radiometric dating methods measure isotopes in some way. Most directly measure the amount of isotopes in rocks, using a mass spectrometer. Others measure the subatomic particles that are emitted as an isotope decays. Some measure the decay of isotopes more indirectly. For example, fission track dating measures the microscopic marks left in crystals by subatomic particles from decaying isotopes. Another example is luminescence dating, which measures the energy from radioactive decay that is trapped inside nearby crystals.

More Info : 

click here ->  Modern Dating Methods

Archaeological Dating Methods (1)

Dating is a technique used in archeology to ascertain the age of artifacts, fossils and other items considered to be valuable by archaeologists.Archaeologists use different dating techniques to determine the age of a particular artifact, fossil,site, or part of a site. Two broad categories of dating or chronometric techniques that archaeologists use are called  relative and absolute dating . Relative dating determines the age of artifacts or site, as older or younger or the same age as others, but does not produce precise dates.Absolute dating methods produce specific chronological dates for objects and occupations.This method is not available to archaeology until well into the 20th century.

Relative dating

Relative dating is the science of determining the relative order of past events, without necessarily determining their absolute age.Methods for relative dating were developed when geology first emerged as a formal science.Stratigraphy is the oldest of the relative dating methods that archaeologists use to date things,it is the science of rock strata, or layers.Stratigraphy is based on the law of superposition-like a layer cake, the lowest layers must have been formed first .Layering occurs in sedimentary rocks as they accumulate through time, so rock layers hold the key to deciphering the succession of historical events in Earth’s past.In other words, artifacts found in the upper layers of a site will have been deposited more recently than those found in the lower layers. Cross-dating of sites is still used today in which one compares geologic strata at one site with another location, and extrapolates relative ages in that manner.This method is used when sites are far too old for absolute dates to have much meaning.

However, geological strata are not always found to be in a neat chronological order. Wind and water erode strata and some areas are uplifted or even tilted. These processes result in geological unconformities , or breaks in the original stratigraphic sequence. In addition, people and other animals dig holes, resulting in a mixing of material from different strata.All of these processes confuse the stratigraphic record. In many cases, however, it is possible to reconstruct the original sequence of strata so that they can be used for relative dating.

For instance, if we find a fossil bone below the strata 3 rock level shown in the illustration above, we assume that the animal most likely lived at a time before that layer was formed. However, we must be careful to note whether or not the fossil comes from the mixed strata zone of the filled in hole.

When two objects are found in the same strata of a site, it is usually assumed that they date to the same time period. This is an application of the principle of association. However, the assumption of contemporaneity may not always be correct. This is due to the fact that one or both of the objects may have been moved or redeposited into a different location. In other words, they may no longer be in their primary context.

Biostratigraphy

Biostratigraphy is the use of fossils in stratigraphy. It relies on the study of in situ fossil distributions. Various fossil groups can be found in different sedimentary environments. The two main environments are land (terrestrial) and sea (marine).When the bones of our early ancestors are found in the same geological strata as those of other animals that are known to have lived only during a specific time period in the past, we assume that these ancestors must also have come from that time. This is referred to as dating by association with index fossils (also known as guide fossils, indicator fossils or zone fossils), or biostratigraphy .

Fluorine Analysis

When bones, teeth, or antlers are found at a site, fluorine analysis can be used to tell us whether or not the animals they were from actually lived at about the same time. This relative dating method is based on the fact that there are specific progressive chemical changes in skeletal remains that result from burial underground. As time passes, the organic components of bone (mostly fats and proteins) are lost primarily through bacterial action. Since these components contain nitrogen, there is a progressive loss of that element. At the same time, percolating ground water deposits trace amounts of fluorine and other elements, such as uranium, into the bone. As a result, the amount of fluorine and other trace elements progressively increase. If the bones of two animals are buried at the same time in the same site, they should have the same relative amount of nitrogen and fluorine. If they do not, they most likely come from different eras, despite the fact that they were found in association with each other.

Fluorine analysis can be used only as a relative dating method because the rate of decay and the amount of dissolved minerals in the ground water varies from site to site.Fluorine analysis is primarily used for verifying whether or not two fossils in the same strata at a site were in fact contemporaneous. If not, then at least one of them must be physically out of context.

A good example of the value of fluorine analysis was in bringing to light the Piltdown Man hoax. In 1912, Charles Dawson, an amateur paleontologist, found what was thought to be an early human skull and jaw in the Piltdown gravel deposits of England. Because it had an ape-like jaw and was found in association with the bones of extinct animals, this "Piltdown Man" was also believed to be a very ancient human. It was popularly referred to as "the missing link" in human evolution. In 1949, the Piltdown bones were finally tested for fluorine content by Kenneth Oakley and the fraud became apparent. After reexamining the strata at the Piltdown site, the evidence of a hoax was published in 1953. This was verified through the use of X-ray fluorescence examination. The skull and jaw clearly were not from the same time period. The jaw was likely to have come from a modern young adult orangutan. It had been cleverly carved to fit the skull and stained to look ancient. In addition, the associated bones from extinct animals had much older fluorine and nitrogen ratios than either the jaw or the human skull.

Geochronology

A relative dating method based on the association of early human sites with changing features of the land, such as the advance and retreat of glaciers or the rise and fall of sea levels. When these events are well dated, geochronology could be considered a reliable calibrated relative dating technique.

Artifact time marker

An artifact type that was made by a particular culture during a limited time period. When discovered clearly in association with ancient humans in an archaeological site, they are an indication of at least the relative time of the occupation. When the independent dating of the artifact types is reliable, this can be considered a calibrated relative dating method.

Seriation

When a stratigraphic sequence is lacking, another relative dating technique known as seriation may be applied. This technique dates a site based on the relative frequency of types of artifacts whose dates of use or manufacture are known. The basic assumption underlying seriation is that the popularity of culturally produced items (such as clay pipes or obelisk gravestone markers in America) varies through time, with a frequency pattern that has been called the "battleship curve." An item is introduced, it grows in popularity, then its use begins to wane as it is replaced by another form. Certain types of artifacts have been identified as particularly useful temporal markers, for example, gravestones, projectile points, lamps, pottery sherds.The frequency of artifact types in a stratum can be compared to known frequency changes previously recorded for an ancient culture. In this way, the stratum can be dated relative to other strata or sites. When a seriation sequence has been cross-calibrated with reliable chronometric dating methods, it can be considered a calibrated relative technique. Before being able to interpret materials found at a site, an archaeologist faces the task of sorting the artifacts into manageable units for analysis. This is frequently a difficult task. Sorting is usually based on form and function. What does it look like? What is it made of? Is it decorated in any way? Have you ever seen it before?

Patination

Patination is a technique involving the measuring of the patina on an artifact. The patina is the outermost surface of the artifact that differs in color, texture, luster or composition from the rest of the artifact. This difference is the result of chemical, physical or biological change in response to the surrounding soil and environmental condition. Although it is not an actual dating technique, patination is used when multiple artifacts of the same type are found in the same area and under the same conditions. The use of this technique is to determine the age of the artifacts, relative to the others, by comparing the thickness of the patina on them. There are many variables that have to be calculated, and this makes dating lithics from patina formations a relative dating technique.

Palaeontolgy - Dating by analysing Animal Remains 

This method is based on the assumption that changed climate will bring about the occurrence of different animals and plant species i.e., with change in climate,some species become extinct.This assumption helps in establishing relative dates.

Kinship and Kinship Terminologies

Kinship has traditionally been one of the key topics in social and cultural anthropology. There are two principal reasons for this: First, although not all human groups are constituted on the basis of kinship, all humans have kinship as individuals and are related to other individuals through it. Second, for the sorts of “tribal,” classless, economically unspecialized societies that anthropologists have mostly—though no longer exclusively—studied, kinship has appeared to be the main or even sole form of social organization. As a result, many theoretical approaches, especially the schools of functionalism and structuralism within social anthropology, have focused on how social groups are formed, how individuals are related to one another through kinship, and the mutual rights and duties they have as a result. Cultural anthropologists, by contrast, have chosen to focus more on the symbolic aspects of kinship, such as the meanings attached to being a particular sort of relative, as well as how symbols of and perspectives on personhood, the body, and gender inform kinship ideas and practices. In broad terms, this latter approach has predominated in America since around 1900 but has been reinvigorated periodically and become more influential in world anthropology, especially in the post-structuralist phase starting in the 1970s.

The domain of kinship can be divided into descent (that is, relations between generations), marriage, and siblingship, though there are not nearly as many studies on the last category as there are on the first two. Early work (especially from the functionalist school) tended to see kinship as a matter of descent only, which produced the phrase “kinship and marriage”; later work, starting with structuralism, has tended to include marriage within the overarching rubric of kinship, adding to it the notion of affinal alliance.

The descent theorists (anthropologists limit the term to consangineal relationships,that is,relationships based on ties of blood) include the British Social anthropologists.Their intellectual lineage starts from W.H.R.Rivers and goes through Radcliffe Brown,Evans Pritchard,Meyer Fortes,etc.

The alliance theorists on the other hand, emphasize that kinship includes not only consanguineal relationships but also affinal relationships,that is relationships based on marriage.The "alliance theorists" include anthropologists from America and France like Kroeber,Murdock,Scheider,Claude Levi-Strauss, Louis Dumont, etc.

The Descent theorists emphasize that kinship is a social or cultural recognized consanguineal relationship.The Alliance theorists define kinship as a totality of relationships governed by the rules of consanguinity and affinity.

Note: The relationships based on the consanguineal bond of birth are called descent and relationships based on the affinal bond of sex and marriage are called alliance.

Kinship terminologies :

Anthropologist Lewis Henry Morgan (1818–1881) performed the first survey of kinship terminologies in use around the world. He argued that kinship terminologies reflect different sets of distinctions. For example, most kinship terminologies distinguish between sexes (the difference between a brother and a sister) and between generations (the difference between a child and a parent). Moreover, he argued, kinship terminologies distinguish between relatives by blood and marriage (although recently some anthropologists have argued that many societies define kinship in terms other than blood).

Morgan had amassed a huge amount of data on kinship terminology, and using this he worked out a classification of kinship systems. Morgan assumed that human society had evolved through a series of stages from primitive savagery to civilization, and he saw kinship terminologies as reflecting these stages.

Primitive promiscuity, for example, is signalled by a Hawaiian type of kinship nomenclature. Morgan made two major criterial distinctions between kinds of kinship terms: classificatory terms (provides single term for several persons), which subsume a relatively large number of biological kin types, and descriptive terms (provides specific term for each relation), which subsume relatively small numbers of types - preferably having unique referents. He imposed this scheme on whole terminological systems. He then fitted the typological scheme to his evolutionary framework, where he said that "primitive systems were classificatory, whereas civilized systems were descriptive.Descriptive terminology, in contrast to classificatory terminology, maintains a separation between lineal and collateral kin; for example, mother and mother’s sister, although of the same generation and sex, are distinguished. Descriptive systems are typically found wherever the nuclear family operates as a relatively autonomous unit economically and socially; as a result, they are relatively rare in ethnographic literature.

Descriptive Terminologies

Classificatory Terminologies

Armed with these different terms, Morgan identified six basic patterns of  kinship terminologies: 

Hawaiian kinship: the most classificatory; only distinguishes between sex and generation.
Sudanese kinship: the most descriptive; no two relatives share the same term.
Eskimo: has both classificatory and descriptive terms; in addition to sex and generation, also distinguishes between lineal relatives (those related directly by a line of descent) and collateral relatives (those related by blood, but not directly in the line of descent). Lineal relatives have highly descriptive terms, collateral relatives have highly classificatory terms.
Iroquois: has both classificatory and descriptive terms; in addition to sex and generation, also distinguishes between siblings of opposite sexes in the parental generation. Siblings of the same sex class as blood relatives, but siblings of the opposite sex count as relatives by marriage. Thus, one calls one's mother's sister "mother", and one's father's brother "father"; however, one refers to one's mother's brother as "father-in-law", and to one's father's sister as "mother-in-law".
Crow: like Iroquois, but further distinguishes between mother's side and father's side. Relatives on the mother's side of the family have more descriptive terms, and relatives on the father's side have more classificatory terms.
Omaha: like Iroquois, but further distinguishes between mother's side and father's side. Relatives on the mother's side of the family have more classificatory terms, and relatives on the father's side have more descriptive terms.

Some languages, such as Bengali, Telugu, Tamil, Sinhalese, Chinese (see Chinese kinship), Japanese, Korean, Cambodian, Vietnamese, Hungarian, Bulgarian and Nepalese add another dimension to some relations: relative age. Rather than one term for "brother", there exist, for example, different words for "older brother" and "younger brother".

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Basics - Economic Anthropology

Economic anthropology is a scholarly field that attempts to explain human economic behavior(production,distribution,consumption and exchange) in its widest historic, geographic and cultural scope.Economic anthropology, broadly defined, is the study of material processes in their social relations.It is a sub-discipline with blurred boundaries as it cross-cuts theoretical paradigms and other sub-fields within anthropology. 

As a field of study it is as old as anthropological fieldwork itself.Economic anthropology has gained its identity from its studies of hunter-gather societies, and the following transitions to subsistence production, cash economies,and the market. In the past ten years, the field witnessed also the incursion of new methods, such as field experiments.

According to Dalton, economic anthropology comprises different sets of topics, such as the structure and performance of traditional pre-colonial, preindustrial, colonial, and postcolonial tribal and peasant economies. Bronislaw Malinowski's famous Argonauts of the Western Pacific (1922), challenged the neo-classical assumptions of self-interested and rational motives by illustrating the social and symbolic nature of the Kula exchange system of the Trobriand Islanders. Other early anthropologists focused on the analysis of economic systems, among them Firth (1939), Goodfellow (1939), and Herskovitz (1940). Unlike the approach of Malinowski, these anthropologists employed aspects of neo-classical economics, portraying economic decisions as individual actions based on individual motivation.

Post-World War II, Economic Anthropology was highly influenced by the work of economic historian Karl Polanyi. Polanyi drew on anthropological studies to argue that true market exchange was limited to a restricted number of western, industrial societies. Applying formal economic theory (Formalism) to non-industrial societies was mistaken, he argued. In non-industrial societies, exchange was "embedded" in such non-market institutions as kinship, religion, and politics (an idea he borrowed from Mauss). He labelled this approach Substantivism. The Formalist vs Substantivist debate was highly influential and defined an era.

As globalization became a reality, and the division between market and non-market economies (or between "the west and the rest") became untenable, anthropologists began to look at the relationship between a variety of types of exchange within market societies. Neo-substantivists examine the ways in which so-called pure market exchange in market societies fails to fit market ideology. Economic Anthropologists have abandoned the primitivist niche they were relegated to by economists. They now study the operations of corporations, banks, and the global financial system from an anthropological perspective.

Economic anthropology is not only a way for us to look at past and modern less "civilized" cultures, but a way to analyze "modern" economies. It analyzes the very things that make up an economy, people.

Areas to be covered for civil services exam : 

-Meaning,scope and relevance of economic anthropology;

-Formalist and Substantivist debate;

-Principles governing production, distribution and exchange (reciprocity, redistribution and market), in communities, subsisting on hunting and gathering,fishing,swiddening,pastoralism,horticulture,and agriculture;

-globalization and indigenous economic systems.

Classification of Tribes in India

The Tribes of India can be classified based on :

(i) Territorial Distribution
(ii) Linguistic Distribution
(iii) Occupational Distribution
(iv) Physical Characteristics
(v) Classification according to Culture Contact

(i) Territorial Distribution

According to the first classification, they may be divided into four important groups :
(a) the tribes living in the northern and north-eastern zone;
(b) tribes inhabiting the central zone,
(c) tribes scattered over the extreme corners of south- western India in the hills and the converging lines of the Ghats; and

(d) small groups in several parts of the country or even within the political boundary of the country.

(a)The most important tribes living between Assam and Tibet may be mentioned the Aka, the Dafla, the Miri, Gurung, and the Aptanic on the West of the Subansiri river, and the Gallong, the Minyong the Pasi, the Padam and the Pangi in the Dehong valley. The Mishmi tribes live in the high ranges between the Debong and Lohit rivers, the Chulikata and Belejiyas on the western and the Digaree and the Meju on the eastern parts. Farther east are found the Khamtis and the Singhops and beyond them, converging on the south are the different Naga tribes occupying the mountain valleys on both sides of the Patkois.

The Naga tribes consist of five major groups: the Rangpan and the Konyak in the northern; the Rengma and the Sema, and the Angami in the western; the AoLahota, Phom, Chang, Santam and the Yimstsunger in the central; the Kacha and the Kabui in the southern and the Tangakhul and theKalyo-Kengu in the eastern section. South of the Naga hills running through the States of Manipur, Tipperah, the Chittagong hill tracts live the Kukis, the Lushais, the Lakhers, the Chins, the Khasis and the Garos, many of whom are really overflows of the tribes from across the Frontiers or are closely related. In the Sub-Himalayan region in Sikkim and the northern portions of Darjeeling, there are a number of rather primitive tribes of whom the Lepchas are the best known. In U. P. and UTK also a number of tribes such as the Tharus, Bhoksa, Khasa, Korwa, Bijar, Bhuia, Majhi, Cheri, Raji, and Kharwar are found. 

(b) The central or the middle zone is separated from the north-eastern zone by the gap between the Garo hills and Rajmahal hills and consists of plateaus and mountainous belt between the Indo- Gangetic plain to the north and roughly the Krishna river to the South.

In this zone we have another massing of tribal peoples in M. P. with extensions in U.P.,UTK, MP,Chattisgarh and AP, Southern Rajasthan, Northern Maharashtra, Bihar,Jharkhand, Orissa. Northern Rajasthan, Southern Maharashtra and Bastar form the peripheral areas of this zone. The important tribes inhabiting this zone beginning from the Eastern Ghats and Orissa hills are the Savara, Gadabi, and Borido of the Ganjam district; the Juang Kharia, Khond, Bhumij and the Bhuiya of the Orissa hills. In the plateau of the Chota Nagpur live the Mundas, the Santhals, the Oraons, the Hos and the Birhors. Further west along the Vindhya ranges live the Katkaris, Kols and the Bhils, the latter extending as far as north-west as the Aravalli hills. The Gonds form the largest group and occupy what is known as the 'Gondwanaland' and extend southwards into AP and Chattisgarh.On both sides of the Satpuras and around the Maikal hills are found similar tribes like the Korku, the Agaria, the Pardhan and the Baigas. In the hills of Bastar State live some of the most picturesque of these tribes, the Murias, the Hill Murias of the Adbhujhamar hills and the Bison- horn Marias of the Indravati valley. Majority of these people show similarity of race and culture.

(c) The third zone consists of that part of the Southern India which falls south of the river Krishna (below latitude 16 N) stretching from Wynaad to Cape Comorin.AP,Karnataka,TN,Kerala fall within this zone. From the fact that they occupy these marginal areas and also from the records in the oldest Tamil literature of the Sangam period they appear to be one of the most ancient and primitive inhabitants now living in India having been pushed by the intrusion of more advanced people into their present habitats, where safety and shelter were found against increasing pressure.

Beginning from the north-east the Chenchus occupy the area of the Nallaimallais hills across the Krishna and into the AP State. Along the western Ghats from the Koraga of South Kanara, the Yeruvas and the Todas living in the lower slopes of Coorg hills; the Irulas, Paniyans and Kurumbas of Wynaad, and stretching almost to Kaniya Kumari along the ranges of Cochin and Travancore and sheltered in the isolation of the forest are found the most primitive of Indian aboriginal such as Kadars, Kanikkars, Malvadan, Malakurvan, with many of their original traits still preserved. 

(d) In addition to these three major zones there is a fourth small and isolated zone consisting of Andamans and Nicobar Islands. The main tribes  living in this zone are the Jarawa, Onge, North Sentineless, the Andmanese and the Nicobarese,though separated from the main body of India's aboriginal tribes are ethnically connected with them. 

(ii) Linguistic Affiliation

Linguistically these tribes may be divided into a number of groups based on their affiliation to the various families of languages :

(a) The Austro-Asiatic linguistic branch under which come the Kol or Munda speeches of the Central and Eastern India, Khasi of Assam. Nicobarese in the Nicobar Islands.

Santali found in Bihar,Jharkhand, Orissa, West Bengal and Assam; Mundari; Ho; Kharia ; Bhumij , Garo ; Khasi and few other which  belong to Bihar and Assam. The language of Korku is spoken in M. P. and Berar; while Savana (Saora) and Gadaba are spoken in Orissa. Outside the Kol group, there is the language of Nicobarese in the Nicobar Islands.

(b) The Dravidian Linguistic Group is popular in Central and Southern India. It is spoken by Gonds Gondi in M. P.,Chattisgarh, AP States ; Khondh or Khond in Orissa ; Kui ; the Kurukh or Oraon in Bihar,Jharkhand and Orissa ; Mai to in Rajmahal hills in Bihar. The other tribes under this group are : Maler, Polia, Saora, Koya, Paniyan, Chenchu, Irulas, Kadar, Malser and Malakurwan.

(c) The Tibeto-Chinese (Sino-Tibetan) family includes the tribal languages of various people belonging to the Mongoloid element and found along the southern  slopes of the Himalayas, from northern Punjab to Bhutan and also in northern and eastern Bengal and in Assam, e.g., the Nagas, the Kuki, the Abhors, the Dafla, the Miris, the Khasi and the Mikirs.

(iii) Occupational Classification

The tribes of India not only speak different languages, but also have distinctive economy of their own. They live in different economic stages ranging from food gathering and hunting through shifting cultivation to settled plough cultivation, e.g., the Birhot, Kharia, Korua and Hill Maraia,Malapantaram, Kadar, the Paniyan, etc. The Paliyan depend on food-gathering and hunting for their livelihood. The Baiga, Pauri (hill) Bhuiyan, Jhuang Maria, Khond, Naga and Kutia Kandh are shifting cultivators.

The Munda, Bhils, Baiga, Gond, Majhwar,Kharwar and Ho Santal and Oraon depend primarily on permanent plough cultivation for their living. The Naga tribes have developed a system of terraced cultivation with elaborate means of irrigation by aqueducts.

Dr. Hutton classified these tribes into three groups : (i) Primitive tribes collecting forest produce, (ii) Primitive tribes, pastoral and (iii) tribes practicing settled agriculture(who keep poultry, rattle, know weaving, spinning,pottery and terraced farming) , hunting, fishing and industries.

(iv) Physical Characteristics 

(a)Physically the tribes of the north-east frontier are Mongoloid with light skin colour, straight and -dark hair and flat nose and prominent cheek bones. Majority of them are of medium stature with long heads, scanty hair growth on body and face and almond-shaped eyes. All these tribes, including the women, are muscular with great development of calf-muscles. They are great mountaineers and carry considerable amount of loads to high altitudes. They are healthy, hard-working and of independent spirit and their life is well balanced with democratic councils and considerable stress on personal liberty of thought and action. They have childlike simplicity and are very honest but not trained for sustained labour and concentration of mind. This type is represented by the Nagas, semi-Nagas, Chakmas, Mughs, and Lepchas.

(b) In the central zone the Negrito strain is most marked. The tribes very largely conform to the pattern of what are called the "Austroloid characters." Physically they are from short to medium stature, dark skinned with long head, and generally possessing curly but not frizzly hairs, road and flat nose but depressed at the root, fleshy everted lips. They are strong, muscular and well-built. This type is represented by the tribes like the Chenchus, Kurumbas, the Yeruvas, Malayans, Munda, Kols, Santhals and the Bhils.

(c) In the southern zone there is an undoubted Negrito strain, although at present greatly submerged, but still surviving among some of the more primitive and isolated of these tribes such as the Kadars of Perambiculam, hills of Cochin,and the Irulas and Panyans of the Wynaad. Physically they are of short to medium stature, of deep chocolate brown skin colour, small head, bulbous forehead, smooth brow- ridges and feeble chins.
The face is short and protruding and the nose flat and broad and the lips are thick and everted, the head shape is long, hair fine and of wooly nature and the body well developed.

At the present time they are greatly intermixed and it is only in the extreme interior that more archaic types are to be found.

Note : Tribes in India 

1.According to Risley's Classification - Dravidian and Mongoloid Groups
2.According to Guha Classification - Negrito,Proto-Australoid,Mongoloids(Paleo and Tibeto)

3.According to Sarkar's Classification-Australoid,Mundari speaking,Far-Eastern,Mongoloid

(v) Classification according to culture-contact

There are four main cultural divisions among the aboriginals. The first two classes consist of the comparatively small block of real primitives living in the hills. Their religion is characteristic and alive ; their tribal organisation is unimpaired ; their artistic and choreographic traditions are unbroken; their mythology still vitalizes the healthy organism of tribal life. Geographical conditions have largely protected them from the debasing contacts of the plains".

The wilder aboriginals have to be sub-divided into two sections :

(a) the first class in the most primitive and simple stage of all is comprised of Hill Marias of Chattisgarh State, the Juangs of Keonjhar and Pal-Labara, the Gadabas and Bondos of Orissa, the Baigas, andaria and Kawaedha, many of smaller communities and more isolated villages even of comparatively sophisticated tribes.

This group has the following characteristics :

(i) Its members live a largely communal life like those of the Hill Marias, Hill Baigas and the Juangs
(ii) Economically they share one another ;
(iii) Their life still centres round a peculiar form of agriculture (Jhum) and
(iv) They are shy of strangers but among themselves honest, simple and innocent. Crime is rare and women virtuous.

(b) The second class of aboriginals live in country equally remote and they are equally attached to their solitude and to their ancient traditions but they have begun to change in many ways. The important tribes of their class are Bison-horn Marias or the Bhomia and Binjhwar and Baigas. 

Their chief characteristics are :(i) Their village life has become individualistic, (ii) They no longer share things with one another, (iii) Axe-cultivation is more a habit rather than a part of their life ; (iv) They are more accustomed to outside life and are generally less simple and honest than the above class.

(c) The third class of aboriginals is the most numerous. It consists of all those who under the influence of external contact have begun to lose their stronghold on tribal culture, religion and social organisation.

(d) The fourth class, which consists of the old aristocracy of the country represented today by the great Bhil, Naga chieftains, the Gond Rajas, a few Bin jh war and Bhiuya landlords, Korku noblemen, wealthy Santhal and Utaon leaders and some highly cultured Mundas. These retain the old tribal name and their clan and totem rules and observe elements of tribal religion though they generally adopt the full Hindu faith and live in modern style.

Process of Transformation of Tribal Cultures

The process through which the tribal cultures are usually transformed or modified may be either :

(i) simple adoption, which means the acquisition of technical skill, adoption of tools, implements, ideas, customs and rites by one social group from another, e.g. the Warli of Thana district is yet simple and unostentatious, put on a loin cloth without anything on his head but his colleague in the south being in much contact with the Kolis puts on a shirt, dhoti and turban after the latter's fashion. Similar taking over of the elements of material culture from neighbouring groups is found in all tribes today especially the Bhils, the Gonds and the Santhals, etc.

(ii) Acculturation is the process of change due to contacts with other people. It involves acceptance and adoption. A tribe in contact with civilization may accept some of the traits of their neighbours such as the employment of Hindu priest in indigenous ceremonies and festivals among some of the tribes in Bihar is an example of simple acceptance. Similarly Munda tribes have accepted some of the cultural traits from their neighbours, while Raj ban sis have shown an adaptation to Hindu culture. The Lambadis of the Deccan have taken to agriculture, they have adopted the dress of their neighbours and tribe is divided into sections based on occupations. Similar adaptation is found among certain sections of the Gonds, the Raj Gonds and the Navgharia Gonds and the Bhils.

(iii) Assimilation, by a gradual drift to Hinduism. When certain members of a primitive tribe move down into the plains they tend to become assimilated in contrast to other members who remain behind. The evidence of assimilation in many cases is apparent. Certain Santhals of Bengal give distinctly Hindu names to their children, practise child-marriage before the age of 7, revere the Tulsi plant, abstain from beef, cleanse "their living quarters with cowdung, decline food cooked by Muslims, cremate their dead and place the vermillion mark and the iron bangle upon their wives."

Effects of Culture Contacts

The effects of such contacts have been very far-reaching on the life of the aboriginals. Contacts with civilisation have undermined social solidarity, invaded tribal security, introduced discomforts, diseases and vices. The results may be detailed as below :

(i) The rapid opening up of the means of communications has resulted more in conflict than in useful contact not necessarily a conflict of arms but of culture and material interest. Says Dr. Hutton, "Attempts to develop minerals, forests or land for intensive cultivation can only be made at the expense of the tribes whose isolation is thus invaded : tribal customs which regulate the ownership or transfer of land are normally superseded by a Code in the application of which the tribe is deprived of its property, generally in the name of law, either by alienation to foreigners or by transferring the trusteeship of a tribal chief into absolute ownership of a kind foreign to the customs of a tribe. The complicated system of administration of justice has tended to impair the natural truthfulness and honesty of the people and social solidarity of the tribes has weakened the authority of the social heads and the respect they formerly commanded." In spite of the best intentions a lot of injustice is done to the aboriginals by the Judges and Magistrates and the police officers of all grades owing to their ignorance of customs and mentality of the aboriginal tribes they have to deal with.

(ii) The introduction of the outstill system in tribal area in mines and industrial centres, where they frequent for employment, has led to an increase in drunkenness and immorality. "The temptation of distilary liquor", wrote Shri S. C. Roy, "introduced by the Government in some aboriginal areas is another evil that is working havoc, economically, morally and physically

(iii) One of the most important effects of contacts has been the spread of diseases in tribal areas. Mills has shown, while writing about the effects on some primitive tribes of Assam of contact with civilization, "That improved communications while they have immensely facilitated internal trade, have undoubtedly spread disease; not only have specific diseases such as venereal diseases and T. B. been introduced but epidemics spread more quickly. The opening of the road to Manipur has led to an increase in prostitution.'' Emigration of labour from tribal areas to plantations and factories where conditions are not favourable to settlement has been the main source for the spread of epidemic diseases. The lure of free life unhampered by social control pulls women to plantations and factories where they are tempted to a corrupt life and the large incidence of V. D. like syphilis and diabetes, gonnorohea, etc., among the labourers is directly traceable to such indiscriminate mixing of the sexes. Missionaries and the philanthrophic agencies have caused T. B., and other contact diseases to spread in tribal areas through indiscretion, as for example, doling out second hand clothes and apparels collected from the dead or diseased population, which are a foci of infection.

(iv) Urban contacts have everywhere disorganised primitive social life. The village has ceased to be living community; it is now an aggregate of isolated units. Old myths are being forgotten and the old gods neglected. Many of the traditional dances which used to provide recreation to the youths of both sexes, translate joys and sorrows are being abandoned and village politics, rivalry and social disputes are replacing their old-time recreation. The effects of this transfer of interests have already been evident in the high incidence of imported diseases, poor physique, inferiority complex and a bitter Antagonism against advanced groups in the neighbourhood.

(v) A large number of tribes have been living on hunting and collection of jungle products supplemented by Jhum cultivation. The effects of Jhum cultivation have led to strict rules regarding denudation of forests and today many of the tribes (who lived by shifting cultivation) have come down to the plains though most have not succeeded in adapting themselves to other kinds of agriculture found in the plains. This is mostly
due to tribal inertia, shyness of the aborigines, apathy of administration and as Dr. Hutton says, may be due to ignorance of appropriate magico- religious ceremonial necessary for other types of farming."

(vi) Many tribes have failed to maintain their tribal structures and have either been assimilated with more vital stock or have withdrawn themselves from contacts as a defensive measure. The Andamanese, Korwas, Todas and Chenchus are on evil days and are preparing themselves for exit. Some other tribes have left their tribal moorings and have settled in the neighbourhood of higher cultural groups whom they serve. Today they have developed some sort of interdependence. The Gond tribe of M. P. and Bhils of southern-eastern Rajasthan may be taken as an example.

(vii) The nomadic tribes who secured their livelihood by catering to the periodical requirements of settled communities as the Marwaris or the Lakhota supplying agricultural implements to the latter or repairing their indigenous tools and utensils, the Nats supplying crude nostrums for the restoration of the lost manhood, the Kanjars providing amusements, acrobatics and dances for the village communities, find it difficult to continue their customary life and have enlisted themselves into the ranks of criminal tribes whose attention to the rural communities is a perpetual concern of the administration.

(viii) Lastly, the itinerant seller of goods and trinkets, the moneylender, the licensee of excise shops, collectors of lac, honey and other forest produce are mostly aliens in culture and language. They have settled in tribal areas and have taken advantage of the gradual drift of tribal society from a moneyless economy to one in which exchange depends on the circulation of money. The implications of money economy are better understood by them and thus they have succeeded in solidly entrenching themselves in tribal areas and today they are a source of great discomfort to the tribal people. In many areas the land has passed from the aborigines to the moneylenders and sahukars who make the very people work for them. 

Human Growth and Development - Prenatal Stage

Prenatal development refers to the process in which a baby develops from a single cell after conception into an embryo and later a fetus.The process of prenatal development occurs in three main stages. They are germinal stage, the embryonic stage, and the fetal stage.The first two weeks after conception are known as the germinal stage,the third through the eighth week are known as the embryonic period, and the time from the ninth week until birth is known as the fetal period.The average length of time for prenatal development to complete is 38 weeks from the date of conception.

Three Stages in Prenatal Development :

Germinal stage

Conception occurs when the female egg (ovum) is fertilized by a  male sperm. Under normal circumstances, one egg is released approximately once a month from a woman's ovary during a process called ovulation. The egg makes its way into a fallopian tube, a structure that guides the egg away from the ovary toward the uterus. For fertilization to occur, sperm ejaculated during sexual intercourse (or introduced during artificial insemination) in a substance called semen must have made their way from the vagina into the uterus and subsequently into the fallopian tube where the ovum has been released. This process can take up to ten hours after ejaculation. For fertilization to occur, a sperm must penetrate the tough outer membrane of the egg called the zona pellucida. When one sperm successfully binds with the zona pellucida, a series of chemical reactions occurs to allow only that sperm to penetrate. Fertilization occurs when the sperm successfully enters the ovum's membrane. The genetic material of the sperm and egg then combine to form a single cell called a zygote and the germinal stage of prenatal development commences.

The zygote soon begins to divide rapidly in a process called cleavage, first into two identical cells called blastomeres, which further divide to four cells, then into eight, and so on. The group of diving cells begins to move along the fallopian tube toward the uterus. About sixty hours after fertilization, approximately sixteen cells have formed to what is called a morula, still enclosed by the zona pellucida.Three days after fertilization, the morula enters the uterus. As cell division continues, a fluid-filled cavity called a blastocoele forms in the center of the group of cells, with the outer shell of cells called trophoblasts and an inner mass of cells called embryoblasts. The zona pellucida disappears and the morula becomes a blastocyst. At this stage the blastocyst consists of 200 to 300 cells and is ready for implantation. The blastocyst is made up of three layers. The three layers also known as germ layers are formed by a process called gastrulation.

Those three layers are : 

The ectoderm (which will become the skin and nervous system)
The endoderm (which will become the digestive and respiratory systems)
The mesoderm (which will become the muscle and skeletal systems)

Finally, the blastocyst arrives at the uterus and attaches to the uterine wall, a process known as implantation.

Implantation, the process in which the blastocyst implants into the uterine wall, occurs approximately six days after conception. Hormones secreted from the mother's ovaries and a chemical secreted by the trophoblasts begin to prepare the uterine wall. The blastocyst first adheres to the wall then moves into the uterine tissue.Implantation is not always an automatic and sure-fire process. Researchers estimate that approximately 58 percent of all natural conceptions never become properly implanted in the uterus, which results in the new life ending before the mother is ever aware she is pregnant.When implantation is successful, hormonal changes halt a woman’s normal menstrual cycle and cause a whole host of physical changes. Implantation marks the end of the germinal stage and the beginning of the embryonic stage.

Embryonic stage

The embryonic stage begins after implantation and lasts until eight weeks after conception. Soon after implantation, the cells continue to rapidly divide and clusters of cells begin to take on different functions (called differentiation). A process (gastrulation) leads to the formation of three distinct layers called germ layers: the ectoderm (outer layer), the mesoderm (middle layer), and the endoderm (inner layer). As the embryo develops, each germ layer differentiates into different tissues and structures. For example, the ectoderm eventually forms skin, nails, hair, brain, nervous tissue and cells, nose, sinuses, mouth, anus, tooth enamel, and other tissues. The mesoderm develops into muscles, bones, heart tissue, lungs, reproductive organs, lymphatic tissue, and other tissues. The endoderm forms the lining of lungs, bladder, digestive tract, tongue, tonsils, and other organs.The process of differentiation takes place over a period of weeks with different structures forming simultaneously.

 Some of the major events that occur during the embryonic stage are as follows:

-Week 3: Beginning development of the brain, heart, blood cells, circulatory system, spinal cord, and digestive system.
-Week 4: Beginning development of bones, facial structures, and limbs (presence of arm and leg buds); continuing development of the heart (which begins to beat), brain, and nervous tissue.
-Week 5: Beginning development of eyes, nose, kidneys, lungs; continuing development of the heart (formation of valves), brain, nervous tissue, and digestive tract.
-Week 6: Beginning development of hands, feet, and digits; continuing development of brain, heart, and circulation system.
-Week 7: Beginning development of hair follicles, nipples, eyelids, and sex organs (testes or ovaries); first formation of urine in the kidneys and first evidence of brain waves.
-Week 8: Facial features more distinct, internal organs well developed, the brain can signal for muscles to move, heart development ends, external sex organs begin to form.

 By the end of the embryonic stage, all essential external and internal structures have been formed. The embryo is now referred to as a fetus.

 Fetal stage

This period of develop begins during the ninth week and lasts until birth. Although all of the organ systems were formed during embryonic development, they continue to develop and grow during the fetal stage.The fetus continues to grow in both weight and length.This stage of prenatal development lasts the longest and is marked by amazing change and growth. During the third month of gestation, the sex organs begin to differentiate and by the end of the month all parts of the body will be formed.

When an embryo becomes a fetus at eight weeks, it is approximately 3 centimeters (1.2 inches) in length from crown to rump and weighs about 3 grams. By the time the fetus is considered full-term at 38 weeks gestation, he or she may be 50 centimeters (20 inches) or 3.3 kilograms .

Examples of some of the major features of fetal development by week are as follows:

-Weeks 9–12: The fetus reaches approximately 8 cm in length; the head is approximately half the size of the fetus. External features such as the face, neck, eyelids, limbs, digits, and genitals are well formed. The beginnings of teeth appear, and red blood cells begin to be produced in the liver. The fetus is able to make a fist.
-Weeks 13–15: The fetus reaches approximately 15 cm  in length. Fine hair called lanugo first develops on the head; structures such as the lungs, sweat glands, muscles, and bones continue to develop. The fetus is able to swallow and make sucking motions.
-Weeks 16–20: The fetus reaches approximately 20 cm in length. Lanugo begins to cover all skin surfaces, and fat begins to develop under the skin. Features such as finger and toenails, eyebrows, and eyelashes appear. The fetus becomes more active, and the mother can sometimes begin to feel fetal movements at this stage.
-Weeks 21–24: The fetus reaches approximately 28.5 cm in length and weighs approximately 0.7 kg . Hair grows longer on the head, and the eyebrows and eye lashes finish forming. The lungs continue to develop with the formation of air sac (alveoli); the eyes finish developing. A startle reflex develops at this time.
-Weeks 25–28: The fetus reaches approximately 38 cm in length and weighs approximately 1.2 kg . The next few weeks mark a period of rapid brain and nervous system development. The fetus gains greater control over movements such as opening and closing eyelids and certain body functions. The lungs have developed sufficiently that air breathing is possible.
-Weeks 29–32: The fetus reaches approximately 38–43 cm in length and weighs approximately 2 kg . Fat deposits become more pronounced under the skin. The lungs remain immature but breathing movements begin. The fetus's bones are developed but not yet hardened.
-Weeks 33–36: The fetus reaches approximately 41–48 cm in length and weighs 2.6–3.0 kg . Body fat continues to increase, lanugo begins to disappear, and fingernails are fully grown. The fetus has gained a high degree of control over body functions.
-Weeks 36–38: The fetus reaches 48–53 cm in length is considered to be full-term by the end of this period. Lanugo has mostly disappeared and is replaced with thicker hair on the head. Fingernails have grown past the tips of the fingers. In a healthy fetus, all organ systems are functioning.

While prenatal development usually follows this normal pattern, there are times when problems or deviations occur . (Details --> Click Here)

Factors influencing Growth rate

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Prenatal Development - Videos 


Fertilization (Conception)

Weeks 1-9
 

    

Weeks 10 - 14

Weeks 15 - 20

Weeks 21 - 27

Weeks 28 - 37

Development of sexual organs

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Dances of India

Dance in India has a rich and vital tradition dating back to ancient times.The Indian dances are broadly divided into Classical dances and folk dances.The Classical dances of India are usually spiritual and religious in content.Indian Classical dance is also known as the traditional Indian dance which has abundant forms and takes human figure as its basic medium of expressions. Like the Indian culture, Indian classical dances are equally diverse in nature.The folk dances of India are also spiritual and religious in content but the main force behind the folk dances of India is the celebratory mood.There are numerous classical dance forms in India and innumerable folk dances.Each dance form can be traced to different parts of the country. Each form represents the culture and ethos of a particular region or a group of people.

Classical Dances

India has a very rich tradition of classical dance. Each form has its own specialty & grace, along with a set pattern of costumes & make-up.Indian classical dance is a relatively new umbrella term for various codified art forms rooted in Natya, the sacred Hindu musical theatre styles, whose theory can be traced back to the Natya Shastra of Bharata Muni (2nd century BC).Even though the art of Natya includes nritta, or dance proper, Natya has never been limited to dancing and includes singing, abhinaya (mime acting). These features are common to all the Indian classical styles.The foundation of the conventions and methodical movements and types of dance lies in an ancient book of dance, music and drama called Natyashastra.

According to a popular belief, Brahma, the Creator of the World, combined literature from the Rig Veda, songs from the Sama Veda, abhinaya (expression) from the Yajur Veda and rasa (aesthetic experience) from the Atharva Veda, to form natyashastra .It has has over 36,000 verses. Natyashastra is also known as fifth veda.It explains the nuances of dance, giving stress on mudras (hand formations) and their meanings, the kind of emotions and their categorization.Apart from the abhinaya and the performance of rasa, the audience is amused by the attire and ornaments of the artist. The majority of Indian classical dance forms are focused on the depiction of the nine rasas (Navarasas or the emotions), which includes Hasya (happiness), Krodha (anger), Bhibasta (disgust), Bhaya (fear), Shoka (sorrow), Viram (courage), Karuna (compassion), Adbhuta (wonder) and Shanta (serenity). 

As per the ancient treatises, dance is considered as having three aspects: natya, nritya and nritta. Natya highlights the dramatic element and most dance forms do not give emphasis to this aspect today with the exception of dance-drama forms like Kathakali. Nritya is essentially expressional, performed specifically to convey the meaning of a theme or idea. Nritta on the other hand, is pure dance where body movements do not express any mood (bhava), nor do they convey any meaning. To present nritya and natya effectively, a dancer should be trained to communicate the navarasas.

Sangeet Natak Akademi, the national academy for performing arts, recognizes eight distinctive traditional dances as Indian classical dances, which might have origin in religious activities of distant past.They are:

1.       Bharatanatyam - Tamil Classical Dance
2.       Odissi - Orrisa Classical dance
3.       Kathakali - Malayalam Classical Dance
4.       Kathak - North Indian Classical Dance
5.       Manipuri - Manipur Classical Dance
6.       Kuchipudi - Telugu Classical dance
7.       Mohiniaattam - Kerala Classical Dance
8.       Sattriya - Asamese Classical Dance

From the Natya Shastra, 3 religious dance/drama forms developed:

Agama Nartanam:  Dances performed inside the sanctum of the temple according to the ritual.  This was a spiritual dance form.
Carnatakam: Dances performed in royal courts to the accompaniment of classical music.  This was an intellectual art form. 
Darbari Aattam: Dances performed more for common Indians which educated them about their religion, culture and social life. These dances were performed outside the temple precincts in the courtyards.

A dance style is classical to the extent it incorporates the Natya Shastra techniques. Some of the styles such as Kathak use very few elements found in Natya Shastra. Other art dances yet to be conferred as classical dances, whose theories and techniques can also be traced back to the Natya Shastra are:

Andhra Natyam - Telugu art dance
Vilasini Nrityam/Natyam - Telugu art dance
Kerala Natanam - Kerala classical dance

Out of the eight recognized dance forms, the only two temple dance styles that have their origin in Natya Shastra and are prescribed by the Agamas are Bharata Natyam and Odissi. These two most faithfully adhere to the Natya Shastra but currently do not include Vaachikaabhinaya (dialog acts), although some styles of Bharata Natyam, such as Melattur style, prescribe the lip and eye movements indicating Vaachikaabhinaya.

Kuchipudi, which also prescribes the lip movements indicating Vaachikaabhinaya, and Mohiniyattam are relatively recent Darbari Aatam forms, just as Kathakali, and two eastern Indian styles, Manipuri and Sattriya, that are quite similar.

Kathak originated as a court dance. Some believe it evolved from Lord Krishna's raas lilas, forms of which have also evolved into the popular Garba-style dances popular in North India and Gujarat. The style gradually changed during the Mughal period under the influence of Persian dance, a major change being straight knees instead of the bent knees used in most other Indian classical forms. Intricate footwork and spins, as well as abhinaya, are the highlights of Kathak.

Currently, Sangeet Natak Akademi does not consider the recently reconstructed dance styles of Andhra Pradesh such as Andhra Natyam and Vilasini Natyam as "classical." Bharatanrithyam, despite being the one most closely following Natya Shastra's precepts, is considered as a variety of Bharata Natyam.

Folk Dances

Folk dance in India is a term broadly used to describe all forms of folk and tribal dances in regions across India(These types of dances can be categorised into two major categories: Folk and Tribal dances).Folk dances are numerous in number and style, and vary according to the local tradition of the respective state, ethnic or geographic regions. There are cultural differences between the two forms- folk and tribal dances- the folk dances are the rural extensions of the larger Indian population for example Bhangra of Punjab and Garba of Gujarat. However, the tribal dances are dances by adivasis, which have a very different culture from the larger Indian population. It may be noted here that Indian tribal dances are vastly dissimilar from Indian folk dances, which can never be related. A common example of a tribal dance is the Santhali Dance, indigenous from Chottanagpur region. Other tribal dances of India include the Dhimsa dance by Oriya tribes, the Dhimsa dance, yet another tribal dance from Andhra Pradesh, the Nagaland tribal dances,etc. Each of these aboriginal tribes possesses its own distinguishable dance traditions and invariably all of them are interwoven with the life of the people who dance it.

Indian Folk dances have originated with a view to be a creation of different socio-economic set up and traditions. While Indian classical dance is considered a higher form of art and was practiced in courts, temples and on special occasions, folk dance forms are practiced in groups in rural areas as an expression of their daily work and rituals.  Indian folk as well as tribal dances are simple and performed to express joy and performed to celebrate a season, festivals and so on. Its simplicity is shown by its less movement and uncomplicated steps.Some of the popular folk dances that are performed across villages and cities are Bhangra, Garba, Kalbelia and Bihu.Many folk dances are devoted to the presiding God of the specific community. The most appealing element of a folk dance is the requisite outfit for its performance. In Indian Folk Dances the accessories play a vital role, these costumes provide a separate identity to the folk dance. Many a time, folk dances are termed as per the name of the accessory used.

Almost all the regions of the country have their specific folk music and dance, which proves to be a wonderful way of expression of their community and its traditions. Though these folk dances are not as complex as the classical dance forms, they are very beautiful, because of the essence of rawness in them. Folk dances are performed for every possible occasion, to celebrate the arrival of seasons, birth of a child, a wedding and festivals. The folk dances are extremely simple with minimum of steps or movement. Indian folk dances are full of energy and vitality. Some dances are performed separately by men and women while in some performances men and women dance together. On most occasions, the dancers sing themselves, accompanied by artists with instruments. Each form of folk dance has a specific costume and rhythm. Most of the costumes, worn for folk dances, are colorful with extensive jewels and designs.

List of Indian Folk Dances -- Click Here

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