DK Nature: Senses
Animals use their senses to find out about the world around them. Most have the same five senses as humans, but some have extra senses, such as ECHOLOCATION.
Many animals have far sharper senses than humans. Sight is our most important sense, but birds such as falcons have much sharper vision. Some insects can detect ultraviolet light, which we cannot see. A bloodhound’s nose is many times more sensitive than a human’s. Bats, whales, and elephants can detect very high or low sounds that we cannot hear.
Some animals can see quite clearly at night even when there is no moon. The large eyes of nocturnal hunters, such as owls, are designed to make the most of very dim light. Many animals active at night also have extremely good senses of hearing and smell.
Some aquatic animals, including sharks, can pick up tiny electrical signals given off by their prey. It is believed that many migratory animals can detect Earth’s magnetic field to help find their way.
Bats, whales, and dolphins, which hunt in darkness or murky water, make sounds, then listen for echoes to track their prey. The same technique helps them to navigate and avoid collisions with objects.
Hunting bats and dolphins make streams of clicking sounds, which spread out through the air or water. The sound vibrations bounce back off objects such as flying insects or shoaling fish. The hunter uses its sharp hearing to listen for the returning echoes. These allow it to pinpoint the whereabouts of its victims, so that it can home in on its prey.