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Question
Read the following statement and justify the same in your own words with the help of a suitable example.
Geographical and reproductive isolation of organisms gradually leads to speciation.
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Solution
- Every species survives in specific geographical conditions, as the food and habitat requirements are specific for each species.
- Their reproductive ability and period are also different, so the individuals from one species cannot reproduce with individuals from other species.
- When they are separated by a distance or geographical barriers, they are said to be isolated geographically.
- When they cannot reproduce with each other, they are said to be isolated reproductively.
- The ancestor species of both these groups may be the same, but due to isolation over a very long-time duration, there is genetic variation between them. Therefore, this continuous isolation ultimately leads to speciation.
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