Bill Shull, age 10, of Lake Jackson, Texas, for his question:
Which are the biggest and smallest mammals?
There is no question as to which is the biggest of all the mammals. He is the blue baleen whale, at home in the deep waters of the Atlantic and the Pacific. Not only is he the largest mammal alive, he is the largest animal that has ever lived on land or sea. In 1948 a specimen weighing 300,000 pounds was caught in Antarctic waters. His body was cut up and weighed on the scales bit by bit ‑ 150 tons of him.
The blue whale is also a powerful animal. He can swim at 27 miles an hour, faster than a freighter. He is estimated to have the pulling strength of 400 horsepower. The red meat and the rich oil from such a whale may be worth $15,000 to $20,000 or more.
Surely this mighty animal must be the terror of the seas. Not at all. The monster is a gentle giant. He does not eat meat so has no need to take life. Few dwellers of the sea are foolish enough to attack him. So he has little need to defend himself.
The big fellow is streamlined and 80 or 90 feet long. He glides through the water seeking seafood salad. His food is called plankton. It is a mass of microscopic plants and animals afloat in the water. The big whale's massive mouth is lined with strips of horny baleen. They hang in curtains from the roof of his mouth and act like a strainer. The whale takes a mouthful of plankton filled with water, squeezes the water through the baleen with his tongue and swallows the mush. He needs about one ton of this mush each day.
Baby Blue Whale is about 20 feet long and weighs about 25 tons. Even he, compared with the smallest of mammals, is a monstrous fellow, indeed. This tiny creature is a shrew and her babies are no bigger than bumblebees. Full grown, she weighs about as much as a teaspoonful of water. She is too light to be measured in ounces. Mama Shrew tips the scales at about three grams and ten of her babies together weigh about one gram. The pigmy shrew, smallest of them all, is but two inches long, plus an inch of tail.
There may be dozens of these tiny mammals in your favorite meadow. Chances are you would never notice them. They live out of sight, just below the surface. There they scurry for their food under grass roots and among the leaves.
Surely the little shrew must be a very timid animal. Not at all. The small creature is bold and ferocious. All the meat eating birds and mammal try to kill him. He is ready, with sharp pronged teeth, to defend himself. He is a meat eater, feeding on caterpillars and such. He is in competition with other shrews and always ready to fight.
Both the huge whale and the tiny shrew are mammals, but what a different in size as well as disposition. The largest animal on earth is an easygoing fellow, harmless and gentle. The tiny shrew is vicious and blood thirsty, perhaps the most blood thirsty of all the mammals.