What is common to whale seal and shark

Options

A. Seasonal migration
B. Thick subcutaneous fat
C. Convergent evolution
D. Homeothermy

Explanation

To answer the question "What is common to whale, seal, and shark?", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Animals**: Recognize that the animals in question are the whale, seal, and shark. All of these are aquatic animals.

2. **Examine Their Habitat**: Understand that all three animals live in water and have adapted to an aquatic lifestyle. This is a common characteristic.

3. **Review the Options**: Look at the provided options to determine what might be common among these animals:
- **Option 1**: Seasonal migration
- **Option 2**: Thick subcutaneous fat
- **Option 3**: Convergent evolution
- **Option 4**: Homeothermy

4. **Analyze Each Option**:
- **Option 1 (Seasonal migration)**: This is primarily exhibited by whales. Seals and sharks do not typically migrate seasonally, so this option is incorrect.
- **Option 2 (Thick subcutaneous fat)**: Whales and seals have thick subcutaneous fat for insulation, but sharks do not. Therefore, this option is also incorrect.
- **Option 3 (Convergent evolution)**: This is the correct option. Although whales, seals, and sharks do not share a common ancestor, they have developed similar adaptations (like fins and streamlined bodies) for swimming in water. This is a classic example of convergent evolution.
- **Option 4 (Homeothermy)**: Only whales and seals are homeothermic (warm-blooded), while sharks are not. Hence, this option is incorrect.

5. **Conclusion**: The commonality among whales, seals, and sharks is that they all exhibit **convergent evolution**, which means they have developed similar traits independently due to similar environmental pressures.

### Final Answer:
The common characteristic of whale, seal, and shark is **convergent evolution**.

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