Dolphins are creatures that live in the ocean. Although they live in a similar environment to fish, they have evolved similar body shapes and organs to fish. However, after all, they are not fish, but mammals, so dolphins and fish are quite different, some key characteristics are different. One of the more important differences is the way they breathe. Unlike fish, which breathe with their gills, dolphins breathe with their lungs. This makes it impossible for them to stay in the water for a long time, but they need to surface regularly to breathe, otherwise they may drown. When they breathe, they use their mouth and nostrils to expel the gas from their lungs first, and then inhale fresh gas.
Sometimes small dolphins have difficulty coming up to the surface to breathe. At this time, large dolphins may take care of the small dolphins by lifting them up and letting them come up to the surface to breathe. Larger dolphins will choose their own time to breathe out of the water, and they generally have no great difficulty in emerging from the water.
As mentioned above, unlike the way fish breathe with gills, dolphins use different organs to breathe. The lungs are an important place for gas exchange in dolphins. In addition, the nostrils and mouth are also important organs for dolphins to breathe. The breathing apparatus that dolphins use is similar to that of whales. Dolphins, like whales, have their nostrils on their heads, and when they emerge from the water, they can expel the exhaust from their lungs first, and then inhale fresh air with more oxygen content.
