Giải giúp mik với gấp lắm😭 Dolphins live with the whales in the oceans. But dolphins come much closer to the shore. They will come as close to the shore as you or I can walk without going under water. Dolphins have teeth. Looking at a dolphin you would not think it has a nose, but surprisingly, it does! They have nostrils called blowholes. Over millions of years of evolution, whales’and dolphins’ nostrils moved to the top of their head. This allows them to breath by surfacing instead of them sticking their whole head out of the water. The first thing a newborn dolphin must do is to go to the surface to breathe. But the baby cannot swim so its mother and another dolphin will help push the baby to the surface for its first breath of air. The baby will be able to swim in about 30 minutes. Dolphins navigate by following the hills and mountains of the ocean floor, by tracking the sun, by sensing currents, and by tasting the water along the journey. A dolphin’s sound probably originated in its nasal passages. These nasal passages are located on the top of the head. Dolphins can make sounds to see what lies ahead. This sense is called echolocations. The dolphins’ sound waves hit an object and the echo bounces back.