Class 12th Biology 2011 Set3 Delhi Board Paper Solution
Question 12
Justify with the help of an example where a deliberate attempt by humans has led to the extinction of a particular species.
Answer
Humans try to create the environment according to their well wish without thinking of the organisms. Introduction or elimination of any species or organism may leads to some serious evolutionary change which can be positive or negative. Positive result may enhance the animal’s survival rate that is reproducible, while negative result may result in extinction of native species.
For example:
1. Passenger pigeons and the Stellar’s sea cow are examples of species led to extinction due to over exploitation by humans.
2. Introduction of nile perch in lake Victoria causing extinction of more than 200 cichlid fish.
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