Question

Defination of Theory of evolution

Answer 1

$\huge\tt{Evolution:}$

The production of certain changes taking place over millions of years in the primitive organisms such that new species are produced is referred to as evolution.

Some important sources which provide evidences of evolution includes :

• Fossils;
• Homologous organs; and
• Analogous organs

Theory of EVOLUTION :

1. There is a natural vegetation within any population.
2. Populations remain constant fairly and naturally although all the species produce a large number of offsprings, due to the struggle for survival.
3. The individuals pass on their favourable variations to their progeny from generation to generation.
4. New species are then formed when all these variations get accumulated over a long period of time.

Additional information :

• The theory of evolution was proposed by Charles Darwin in his famous book called "The Origin of Species"

• This theory of Darwin is also known as The Theory of Natural Selection as it suggests that the best adapted organisms are selected by nature such that to pass on their traits to their next generation.

• Theory of evolution applies to both animals and plants.

Answer 2

Answer:

hope it helps

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Darwin’s theory of Evolution: Charles Robert Darwin gave the theory of evolution in his famous book, ‘The Origin of Species’. The theory of evolution proposed by Darwin is known as ‘The Theory of Natural Selection’. It is also called ‘Darwinism’.

According to Darwin’s theory of evolution:

There is natural variation within any population and some individuals have more favourable variations than others.

Population remains fairly constant even though all species produce a large number of off springs.

This is due to ‘competition’ or struggle for existence between same and different species.

The struggle for survival within population eliminates the unfit individuals and those with ‘favourable variations’ survive and pass on these variations to their progeny to continue. This is called natural selection.

The favourable variations are accumulated over a long time period leading to the origin of a new species.

Explanation: