"Bats can ascertain distances, directions, nature and size of the obstacles without any eyes". How ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Echolocation**: Bats use a biological sonar system known as echolocation to navigate and hunt for prey. This system allows them to detect objects in their environment without relying on vision.

2. **Emitting Ultrasonic Sounds**: When bats fly, they emit high-frequency sound waves, which are typically ultrasonic (above the range of human hearing). These sounds travel through the air until they encounter an obstacle.

3. **Sound Reflection**: When the emitted sound waves hit an object (like a tree or an insect), they bounce back towards the bat. This phenomenon is similar to how echoes work.

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