Ken Frankhouse, age 10, of Monroe, Michigan, for his question:

Is a dolphin different from a porpoise?

The porpoise has a neat round nose. The dolphin has a long snout, somevhat like a beak. Both animals belong in the animal order Cetacea, which is the whale clan. They are bath small cousins of the whopping blue whale, the largest animal in the whole world. They also are cousins of the toothy sperm whale and the spike nosed narwhal. All the cetaceans are air breathing mammals. It is believed that their remote ancestors once lived on the dry land. But for some reason, ages ago, they went to live in the sea. Perhaps their favorite food was more plentiful and easier to catch in the ocean.

Nobody, it seems, can have everything. As the cetaceans became better swimmers, they became more clumsy on the land. Neither dolphins nor porpoises can walk and their larger cousins collapse when stranded on a beach. But all cetaceans still breathe air. Both the dolphin and the porpoise have blowholes and neither of them can stay below longer than he can hold his breath.