INSECTS by Ross E. Hutchins, 324 pages, Prentice-Hall. $6.95.
Bugs are little, and easy to look down on. Ever since Charles Darwin decided that man and his almighty brain were winning the amoral marathon of evolution, it has been fashionable to pity the poor insects for entering a blind alley of biology that mammalry was smart enough to miss. To promote a larger sense of reality, Entomologist Ross E. Hutchins in this unusually competent volume of popular science invites the reader to climb modestly down the Tree of Life and to shinny out on a branch of evolution unimaginably larger and in many respects more fruitful than his own.
The insect family, says Dr. Hutchins, is the largest of the animal kingdom. It includes nearly a million species that range in habitat from Antarctic snows to petroleum pools, and vary in size from a fairy fly, which measures about one-hundredth of an inch, to an African goliath beetle, which weighs up to 3.4 oz. and walks around eating bananas, which it peels with its snout.
In strength, insects are incommensurable with mammals; their muscle strands are relatively shorter and more numerous. A highly trained human athlete can expend energy at 20 times his basic metabolic rate, but only for a brief period; any old insect can raise the rate to 50, and keep it up for hours. It is no trick at all for a large African grasshopper to catch and kill a mouse, and giant water bugs commonly capture and devour small snakes. Almost any beetle can lift 850 times its own weight; to do as much, a man would have to lift 62 tons. And the common flea, which measures one-tenth of an inch, can jump twelve inches, or 120 times its own length; to do as much, a man would have to jump 720 feet.
Insects surpass mammals, as a matter of fact, in general biological efficiency.
Their breathing apparatus—a system of tracheae that wander through the body like arteries of air—feeds oxygen to the organs up to 431 times as fast as lungs do. Their circulatory system frequently includes a mechanism that reverses blood flow when a clot obstructs the heart. A male moth's numerous "noses" are so keen that he can smell a female more than a mile away. And as for sex, insects hold the patents on mass reproduction. The East African queen termite lays 43,000 eggs a day, and in a single summer two common houseflies can multiply into 190,000,000,000,000,000,000 irritating insects.