Part 1 of Essay
are mammals closely related to whales and porpoises. have a powerful and streamlined body. They are found in all seas and oceans. can be told apart from porpoises by their nose, which is beaklike, and also their conical teeth. Porpoises have a flatter nose, sharper teeth, and a more solid body. There are 32 known spec ....

Part 2 of Essay
.... by commercial boats for the small amount of oil that can be extracted from their body. This oil is used to lubricate small parts in watches. Cheaper oils have been found, so dolphins are not hunted for this reason anymore. Dolphins can be caught in tuna nets by accident. Since dolphins have to breath at the surface they drown in tuna nets. It is estimated that 4.8 million dolphins were killed in tuna nets from 1959 to 1972. Under pressure from animal rights activists tuna consumers will not accept tuna from c ....