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 The first primitive organisms would arise from further chemical synthesis.
 Stanley L. Miller and Harold C. Urey, conducted the Miller-Urey experiment in
1953 to demonstrate how the life would have originated on the earth.
 They created an environment in laboratory which mimicked the environment of
earth as it was during the time of origin of life.
 Water, methane, ammonia and hydrogen were used in that experiment.
 The liquid was heated to initiate evaporation and electrodes were used to create
electric discharge.
 At the end of two weeks, some organic molecules were formed in the setup.
Some amino acids and sugar were also formed.
 This proved the hypothesis of J. B. S. Haldane that life originated from inorganic
raw materials.

SPECIATION

 The formation of a new species from a pre existing one is called speciation.
 A species is a group of organisms in which most of the characters are similar and
members of a species are able to breed among themselves.
 Speciation can happen if two groups of the same species are somehow
prevented from interbreeding for several generations.

Ways by which Speciation takes place:
 Consider what would happen if the bushes the beetles feed on are
spread widely over a mountain range.
 The beetle population becomes very large as a result. But individual beetles feed
mostly on a few nearby bushes throughout their lifetime.

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