Dolphins are some of the most intelligent animals in the world. They live in warm seas and oceans and are known for their friendly behaviour. Dolphins often swim in groups called pods and communicate with each other using whistles and clicks. Scientists believe that dolphins can even recognize themselves in a mirror, which is a sign of high intelligence. In fact, they often help people at sea, saving swimmers in dangerous situations. Many dolphins are trained to perform in shows where they jump through hoops and play with balls. Moreover, they are studied by biologists who try to understand their social life. Today dolphins are protected in many countries because their population is getting smaller. These animals remind us how important it is to protect the environment and respect wildlife.