Distinguish between hibernation and aestivation.

Explanation

**Step-by-Step Solution:**

1. **Definition of Hibernation:**
Hibernation is a state of inactivity and metabolic depression in endotherms (warm-blooded animals) during the winter months. It allows these organisms to conserve energy when food is scarce and environmental conditions are harsh. During hibernation, an animal's body temperature, heart rate, and metabolic rate significantly decrease.

2. **Definition of Aestivation:**
Aestivation, on the other hand, is a similar state of dormancy that occurs during the hot and dry summer months. It is primarily observed in some animals to avoid heat and desiccation. Aestivation helps these organisms survive in extreme heat and drought conditions by significantly slowing down their metabolism.

...