Why do animals curl into ball during winter ?

Explanation

### Step-by-Step Solution:

1. **Understanding Heat Radiation**:
Heat radiation is the process by which heat is lost from a body to its surroundings. The amount of heat radiated is directly proportional to the surface area of the body. This means that the larger the surface area, the more heat is lost.

2. **Behavior of Animals in Cold Weather**:
During winter or cold weather, animals experience a drop in temperature. To conserve heat, many animals exhibit a behavior of curling into a ball.

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