DOLPHINS AND PORPOISES Dolphins and porpoises are mammals. They breathe air and give birth to living young then they suckle. They belong to the order or group of mammals called cetaceans, which include whales. Dolphins have beaklike mouths. Porpoises have bunt mouths and are smaller than dolphins. But both dolphins and porpoises are toothed whales, and their close relatives include the killer, sperm and pilot whale. Cetaceans are mammals that returned to the sea. Hind …showed first 75 words of 315 total…

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