The genetic information for this work came from a very large collection of gene frequencies for "classical" (non-DNA) polymorphisms of the world aborigines. The data were grouped in 42 populations studied for 120 alleles. The reconstruction of human evolutionary history thus generated was checked with statistical techniques such as "boot-strapping". It changes some earlier conclusions and is in agreement with more recent ones, including published and unpublished DNA-marker results. The first split in the phylogenetic tree separates Africans from non-Africans, and the second separates two major clusters, one corresponding to Caucasoids, East Asians, Arctic populations, and American natives, and the other to Southeast Asians (mainland and insular), Pacific islanders, and New Guineans and Australians. Average genetic distances between the most important clusters are proportional to archaeological separation times. Linguistic families correspond to groups of populations with very few, easily understood overlaps, and their origin can be given a time frame. Linguistic superfamilies show remarkable correspondence with the two major clusters, indicating considerable parallelism between genetic and linguistic evolution.

The constitution provides the reservation of seats in the Lok Sabha and the State Legislative Assemblies.

Demerits of democracy:

• Democracy is all about political competition and power play. There is no scope for morality.
• Consultation in a democracy from many people leads to delays.
• Not knowing the best interest of the people by the elected leaders leads to bad decisions.
• Democracy leads to corruption for it is based on electoral competition.

The units in which they are measured are thus called fundamental units. In this textbook, the fundamental physical quantities are taken to be length, mass, time, and electric current. Physical quantities are classified into two types. There are fundamental and derived quantities. Fundamental or base quantities are quantities which cannot be expressed in terms of any other physical quantities. These are length, mass, time, electric current, temperature, luminous intensity and amount of substance.

There are two sources for information about interior of the earth – a) Direct Sources and b) Indirect Sources:
•Direct Sources: Mining, drilling and volcanic eruption are examples of direct sources. During the process of mining and drilling rocks and minerals are extracted which gives information that there are layer system in the crust. Crust is made of many kinds of rocks and minerals. Volcanic eruption suggests that there is some zone inside the earth which is very hot and in liquid condition. Direct sources are not very reliable because mining and drilling can be done only up to some depth only.
Indirect Sources: Seismic waves, gravitational field, magnetic field, falling meteors etc are example of indirect sources. They are very important for know about earth‘s interior. Movement of seismic wave suggests that there are three layers in the earth and each layer has different density. Density increases toward the center of the earth.

The direct sources are those that provide first-hand information about events whereas the indirect sources involve the reports and analysis of direct information by other people. In scientific disciplines, experiments are the most common direct source; in other disciplines, surveys and interviews, or research into written and oral records of events provide direct access to information. Most of our information about earth's interior has come from seismic studies. Seismic waves produced during an earthquake are recorded by a seismograph when these waves reach the surface of the earth. There are two types of seismic waves- body waves and surface waves.

Four types of seismic waves| Specifications of all types of seismic waves.

• P- Waves (Primary waves)
• S- Waves (Secondary waves)
• L- Waves (Surface waves)
• Rayleigh waves.

 L waves they are dispersive so the particular speed at which they travel depends on the wave period and the near-surface geologic structure, and they also decrease in amplitude with depth. Typical speeds for Rayleigh waves are on the order of 1 to 5 km/s.

Wave is a flow or transfer of energy in the form of oscillation through a medium – space or mass. Sea waves or tides, a sound which we hear, a photon of light travelling and even the movement of small plants blown by the wind are all examples of different types of waves.  L waves they are dispersive so the particular speed at which they travel depends on the wave period and the near-surface geologic structure, and they also decrease in amplitude with depth. Typical speeds for Rayleigh waves are on the order of 1 to 5 km/s.

A published thesis is out in the market printed, usually, in the form of a book. An unpublished thesis is in its primary form and sits in one of shelves in the department of advanced studies getting burried under the dust. Published and unpublished sources. Generally, published sources are international, national, govt., semi-Govt, private corporate bodies, trade associations, expert committee and commission reports and research reports.