Question

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Abingdon tortoise in Galapagos islands became extinct within a decade after goats were introduced.
Reason R: Goats were more efficient at browsing than Abingdon tortoise.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. A is not correct but R is correct
• B. Both A and R are correct and R is the correct explanation of A
• C. Both A and R are correct but R is not the correct explanation of A
• D. A is correct but R is not correct

Hint:

This case study is a classic textbook illustration of Gause's Competitive Exclusion Principle in real-world habitats. Introduced or invasive species often have superior resource exploitation traits, leading to the rapid decline of native species.

Answer 1

The Correct Option is B

Step 1: Identify the ecological idea behind the case.
This is a classic example of interspecific competition, where two species struggle for the same limited resource, here vegetation.
Step 2: Check Assertion A.
Assertion A says the Abingdon tortoise of the Galapagos went extinct within a decade after goats were introduced. This is a well-known documented event, so A is correct.
Step 3: Check Reason R.
Reason R says goats were more efficient at browsing than the tortoise. Goats are agile and crop vegetation faster and lower, so R is correct.
Step 4: Recall the competitive exclusion principle.
Gause's principle says when two species compete for the same limited resource, the inferior one is eliminated.
Step 5: Link A and R.
The tortoises lost out (Assertion) precisely because the goats ate the limited plants more efficiently (Reason), leaving the tortoises starving. So R explains A.
Step 6: Conclude.
Both statements are true and R is the correct explanation of A, which is option 2.
\[ \boxed{\text{Both A and R are correct and R is the correct explanation of A}} \]