Question

What do you understand by the term 'evolution'? State Darwin's theory of evolution.

Answer 1

$\LARGE\underline{\underline{\bf EVOLUTION :}}$

The word evolution mean to unfold or unroll or to reveal hidden potentialities . Evolution simply means an orderly change from one condition to another.

$\huge\textbf{Darwin's\: Theory \:Of \: Evolution : }$

"Darwinism" or "The theory of Natural Selection" was proposed by Charles Darwin and A.R.Wallace. This theory was later on explained by Darwin in his book 'On the origin of species by the means of Natural Selection'.

The Main Features of Theory Of Natural Selection Are as Follows :

$\large\textbf{1.\: Over \: Production :}$

All the organism have capability to produce enormous number of offspring, organisms multiply in geometric ratio .

$\large\textbf{2.\:Struggle \: For \: Existence :}$

Every individual competed with other of the same and other species for basic necessities like space , shelter , and food . It is also called "struggle for existence" and it continues for the whole life from zygote stage to its natural death.

$\large\textbf{3.Variation \: And \: Heredity : }$

According to Darwinism adaptive ability is inherited. It has a genetic basis . Fitness is the end results of the ability to adapt and get selected by nature.

$\large\textbf{4.Survival \: Of \: The \: Fittest:}$

In the struggle for existence only those members survive which posses useful variation means nature selects fit individual. This was called Natural Selection.

$\large\textbf{5.Origin \: Of \: New \: Species :}$

Darwin explained that variations appearing due to environmental changes are transmitted to the next generation repeats so after many generation a new species is formed.