Daniel, a blind man, uses echolocation to perceive the presence of objects, just like Bats. A team runs him through some tests and find that he's able to create a mental image of his surroundings using sound.
Destiny introduces Dory to her neighbor, Bailey, a beluga whale who claims to have lost his ability to find objects using sound waves. Bailey believes that his head is swollen, but Destiny states that his head is naturally that big because of his species.
Beakman explains some information about bats and they have a live bat on the show to show its wings. Then they talk about how bats sleep upside down and are nocturnal. Beakman explains how and why bats use echolocation to find their food.