Identify the incorrect statement.

Options

A. Host specific parasites and their hosts are coevolved.
B. In competition , r(intrinsic rate of natural increase ) of both competing species are decreased .
C. In case of brood parasitism , crow is unable to identify between its own eggs and cuckoos eggs.
D. Introduction of sheeps on Galapagos Islands has resulted in extinction of Abingdon tortoise.

Answer

To solve the question "Identify the incorrect statement," we will analyze each statement provided in the question to determine which one is incorrect.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The statement mentions that host-specific parasites and hosts have co-evolved.
- This is true as parasites adapt to their hosts, and hosts develop mechanisms to combat these parasites.
- **Conclusion:** This statement is correct.

2. **Analyze the Second Statement:**
- The statement discusses competition and the intrinsic rate of natural increase (R) being decreased in both competing species.
- In competitive environments, resources are limited, leading to decreased birth rates and increased death rates, thus lowering R for both species.
- **Conclusion:** This statement is correct.

3. **Analyze the Third Statement:**
- The statement refers to brood parasitism, specifically how cuckoo eggs have become similar to crow eggs, causing crows to misidentify their own eggs.
- This is a well-documented phenomenon in nature, where brood parasites exploit the nesting behavior of other birds.
- **Conclusion:** This statement is correct.

4. **Analyze the Fourth Statement:**
- The statement claims that the introduction of sheep on the Galapagos Islands resulted in the extinction of the Abingdon tortoise.
- However, historical evidence shows that it was actually goats, not sheep, that were introduced and led to the extinction of the tortoise due to their higher browsing efficiency.
- **Conclusion:** This statement is incorrect.

### Final Answer:
The incorrect statement is the fourth one, which incorrectly attributes the extinction of the Abingdon tortoise to the introduction of sheep instead of goats.

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