Science in Christian Perspective

 

 


BIOLOGY

Guest Columnist, Dr. John W. Klotz

From JASA 9 (December 1957): 17-18.

One of the most compelling evidences for the existence of God and for Creation by Him rather than by blind chance is the existence of so many complexities, intricacies, and balances in the biological world. These are so finely adjusted that when man interferes with them or attempts to improve on them he is likely to cause tremendous upsets and bring harm down on his own head.

Perhaps the best example of man's attempt to improve on the balance of nature was the importation into Australia of 24 English rabbits by Thomas Austin in 1859. Because they had no natural enemies they multiplied beyond all expectations and did serious damage. They destroyed much of the grass on which the sheep fed and upset the Australian economy which was dependent on wool. Now that the rabbits have been brought under control through myxoiriatosis, prairies once ravaged by erosion and hills grazed to the soil for decades are miraculously clothed with green. In one recent year the sheep industry alone showed an increased productivity worth about $84,000,000.

A similar situation exists on the Lacquarie Islands where rabbits were introduced to improve the food resources. Soon they began to destroy crops. Here man attempted to repair the damage for which he was responsible by introducing cats. For a time the cats preyed on the rabbits and this was successful, But once the rabbits had been disposed of, the cats attacked the seabirds which the natives greatly prized. Once more man intervened. This time he released dogs to reduce the number of cats. But the dogs preferred seals, which are important adjuncts to the natives' food supply. And so at present, attempts are being made to destroy the dog that man introduced to destroy the cat that man introduced to destroy the rabbit that man introduced.

It is not uncommon that interference with nature to deal with one problem raises another. Stich has been the case with the various drainage projects intended to increase the amount of land available for agrictiltural purposes or to decrease the number of mosquitoes by decreasing their breeding grounds. Though these projects are well intentioned, they are also likely to decrease the number of ducks, for ponds and marshes are their breeding grounds. At one time ducks bred throughout the upper Mississippi Valley; today because of the drainage of swamps and ponds very few ducks breed in the United States: breeding is restricted almost entirely to Canada.

Indeed such ail apparently unrelated thing as an increase in the price of less desirable furs inay lead to a decrease in the number of ducks. One of these less desirable furs is that of the skunk. Turtle eggs form a very important part of the diet of skunks. Turtles, in turn, are important enemies of small ducklings. An increase in the price paid for skunk fur might well lead to an increased trapping of skunks. This insight well lead to an increase in turtles and a consequent decrease in the number of ducks.

Another example of upsetting the balance of nature by trying to solve a biological problem may be seen in what is happening today in one section of Colorado. The ranchers of the Toponas district there, wishing to save their cattle, carried out a campaign to exterminate the coyotes who were attacking their lambs and young calves. The campaign was successful and the coyotes disappeared. Then the ranchers noticed that their pasture land was no longer able to support as many animals as before. With no coyotes to keep them in check, rabbits, gophers, and other rodents began to attack the meadows. While coyotes ate an occasional lamb or calf, they actually did the rancher a favor by keeping these pests tinder control. At present the ranchers there are encouraging the coyotes to breed.

A similar problem is the control of flies and mosquitoes by spraying with DDT and other insecticides.. At one time insecticides-and also herbicides-were rarely necessary. There were a great rnany birds around to eat insects and weed seeds. Today chemical control measures are necessary because the birds have in many cases been driven away. Yet the insecticides being used today are effective not only against mosquitoes and flies but also against useful insects such as the honey bee. Extensive use of DDT in an area might actually reduce the fruit crop in a given area by killing off the pollinating bees and flies, and might upset the balance of nature in other ways. In July 1955 extensive DDT spraying was carried out in Yellowstone National Park and north of the park to control the spruce budworm which attacks the conifers. The result was a reduction in the number of fish in the Yellowstone River. White fish and brown trout were especially adversely affected. These died because of a lack of aquatic insect life on which they relied for food.

The gypsy moth was imported into the United States in 1886. It was hoped that by using this moth a native silk industry could be established. Accidentally it escaped, and the moth has proven to be a serious pest. In 1953 1,500,000 acres of trees in New England were defoliated. About $9,000,000 will be spent this year by federal and state governments to control this pest. ft is hard to conceive of the extent of this insect's activities. While walking through the woods on Cape Cod several years ago it was actually possible to hear the larvac chewing. Auto accidents occurred on highways made slippery by the crushed bodies of thousands of the larvae.

The English sparrow was brought to the United States in the 1850's to control insect pests. By 1875 it had crossed the continent, and today it is itself a serious pest. In 1890 sixty starlings were released in Central Park in New York. Today the starling is also a serious pest.

Even plants can become serious pests. The Canada thistle is an example of such a plant pest. It was introduced into Canada from England and has now become the most noxious weed in our northern states. It spreads rapidly. In some states there are severe penalties for letting it ripen or selling seed which is contaminated with thistle seed.

Actually in most cases God maintains a good balance in nature so long as man does not interfere. And by interfering even with the best of intentions he is more likely to do harm than good. Often we think of the supposed needs of wild animals in our national parks. We attempt to protect them by killing predators and by providing winter feeding for them. Yet in most cases we are not really helping them. The animals killed by predators are relatively few in number. They are the weaklings and probably would not survive long anyhow. In most cases our actual choice is a threefold one: permitting them to be killed by predators, allowing hunters to shoot them, or permitting them to die from exposure during the winter. Yellowstone National Park is an example of a situation in which the balance of nature has been upset. The elk there have few natural enemies because of intensive anti-predator campaigns. They have multiplied to such an extent that they are a real problem. Moreover, they have extended their range into the swamps and marshes which are the ordinary feeding grounds of the moose. The result is that the number of moose is declining.

Now all of this is a powerful testimony to God's wisdom. The balances which He has established are delicate and in most cases almost perfect. Man interferes with them at the risk of doing considerable damage. Man should be very hesitant to attempt to improve on the balance of nature. He is more likely to upset one of these delicate balances than he is to effect real improvement.