Question
Describe the Darwin's theory of natural selection.
✓
Answer
The theory of natural selection stated that carrying capacity of natural resources is limited and in order to survive, the organism struggle for their existence.
(i) In order to cope up, the organism undergoes variations and are able to adapt, so they are naturally selected for survival.
(ii) The theory highlights "Struggle for existence" and "Survival of fittest".
Features of Natural Selection
(1) Struggle for existence :
(i) Organism struggle for its existence because natural resources (food, water and shelter) are limited but the population multiplies rapidly.
(ii) In order to survive, the organism competes for their needs.
(iii) To fulfil their need they modify their organs or traits and adapt according to the environment.
(iv) Organism which are able to adapt classified as superiors.
(v) Superiors exist while the inferiors gets diminished as they are unable to adapt.
(2) Survival for fittest :
(i) Variations are sudden gradual change which helps the organism to adapt.
(ii) The organism which undergoes variation and are fittest to survive and so they are selected naturall.
(iii) The organism after survival transfers the variation from one generation to the other.
(iv) The inheritance of variation eventually leads to speciation.
(i) In order to cope up, the organism undergoes variations and are able to adapt, so they are naturally selected for survival.
(ii) The theory highlights "Struggle for existence" and "Survival of fittest".
Features of Natural Selection
(1) Struggle for existence :
(i) Organism struggle for its existence because natural resources (food, water and shelter) are limited but the population multiplies rapidly.
(ii) In order to survive, the organism competes for their needs.
(iii) To fulfil their need they modify their organs or traits and adapt according to the environment.
(iv) Organism which are able to adapt classified as superiors.
(v) Superiors exist while the inferiors gets diminished as they are unable to adapt.
(2) Survival for fittest :
(i) Variations are sudden gradual change which helps the organism to adapt.
(ii) The organism which undergoes variation and are fittest to survive and so they are selected naturall.
(iii) The organism after survival transfers the variation from one generation to the other.
(iv) The inheritance of variation eventually leads to speciation.
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