Ernestine Garmon, age 12, of Gastonia, for her question:
How many eggs does a fly lay?
The housefly, we are told, is a menace to human health. Some citizens art too lazy to care, but most of us do our share to keep down the fly population. The fly population figures may be astounding enough to cause even the laziest citizens to mend their grubby ways.
Everyone who has tried to swat one has learned that the housefly is one of nature's most agile creatures, who makes full use of his nimble ways. He investigates every open garbage can, every pile of trash in the yard or street. He zooms through your window and makes for your kitchen where he swoops joyfully onto bowls, basins, plates and pitchers of uncovered food.
He seems very small to us, but his world teems with much smaller bacteria and microscopic midgets. Many of these are disease carrying germs. The fly has hairy feet. Wherever he lands, a swarm of questionable passengers sticks to his furry boots and takes off for a free ride. Some will stop over on the fly's landing fields. So swat that fly. Better still, swat a pair of them, for in just one summer season that pair could produce nearly five trillion tons of f1ies.
A female begins to lay her eggs in early april. If all goes well she may lay a batch each week until august, and in each batch there may be 500 eggs or more. If none die, the first parents may have 1,000 children by fall. But there is more to this population explosion. Each batch of eggs may become adult egg laying male in just one week. If half of them are females, the first pair have 125,000 grandchildren.
Every week the first pair starts a new chain of generations, and every week each generation starts its own chain of generations. If none of their offspring die, by the end of summer the original parents could produce offspring numbering 200 followed by 18 zeros, which is 20 times 10 to the 19th power. Since they weigh around 20,000 per pound, this equals some 4.9 trillion tons of flies. Luckily for us only_'a small percentage of this population explosion survives to carry on the staggering production cyc1e the following season.
We swat and spray, cover trash and screen our homes. We aim to cut off the food and destroy the housefly's breeding grounds. And we are aided in this warfare by allies in the world of nature. Hordes of flies and their eggs are devoured by bats and birds, lizards and small snakes, frogs and toads. Most of their extravagant population explosion is sacrificed as food to maintain the balance of nature.