Textbook, A Civic Biology (Full Text)

Head Note: The excerpt below is from the biology textbook used by the State of Tennessee in 1925. The Butler Act made it illegal to teach from textbooks like this one. John Scopes could not remember if he actually taught the section on evolution from this textbook, but volunteered to say that he did in order to challenge the legality of Butler Act. Pay attention to how the textbook explains the theory of evolution.

The Doctrine of Evolution. --- We have now learned that animal forms may be arranged so as to begin with very simple one-celled forms and culminate with a group which contains man himself. This arrangement is caled the evolutionary series. Evolution means change, and these groups are believed by scientists to represent stages in complexity of development of life on earth. Geoloy teaches that millions of years ago, life upon the earth was very simple, and that gradually more and more complex forms of life appeared as the rocks formed latest in time show the most highly developed forms of animal life. The great English scientist, Charles Darwin, from this and other eviidence, explained the theory of evolution. This si the belief that simpple forms of life on the earth slowly and gradually gave rise to those more complex and that thus ultimately the most compex forms came into existence.

The Number of Animal Species. --- Over 500,000 species of animals are known to exist to-day, as the following table shows.


Man's Place in Nature. --- Although we know tht man is separated mentally by a wide gap from all other animals, in our study of physiology we must ask where we are to place man. If we attempt to classify man, we see at once he must be placed with the vertebrate animals becuase of is ppossession of a vertebral column. Evidently, too, he is a mammal, because the young are nourished by milk secreted by the mother and because his body has at least a partial covering of hair. Anatomoically we find that we must place man with the apelike mammals, becasue of those numerous points of structural likeness. Thte group of mammals which includes the monkeys, apes, and man we call the primates.

Although anatomically there is a greater differnce between the lowest type of monkey and the highest type of ape than there is between the highest type of apea and the lowest savage, yet there is an immense mental gap between monkey and man.

Instincts. --- Mammals are considered the highest of vertebrate animals, not only because of their complicated structure, but because their instincts are so well developed. Monkeys certainly seem to have many of the mental attributes of man.

Professor Thorndike of Columbia University sums up their habits of learning as follows:

"In their method of learning, although monkeys, do not reach the human stage of a rich life of ideas, yet they carry the animal method of learning, by the selection of impluses and association of them with different sense-impressions, to a point beyond that reached by any other of the lower animals. In this, too, they resemble ma; for he differs from the lower animals not only in the possession of a new sort of intelligence, but alson in the termendous extension of that sort which he has in common with them. A fish learns slowly a few simple habits. Man learns quickly an infinitude of habits that may be highly complex. Dogs and cats learn more than the fish, while monkeys learn more than they. In the number of things he learns, the complex habits he can form, the variety of lines along which he can learn them, and in their permanence when once formed, the monkey justifies his inclusion with man in a separate mental genus."

Evolution of Man. --- Undoubtedly there once lived upon the earth races of men who were much lower in their mental organization than the present inhabitants. If we follow the early history of man upon the earth, we find that at first he must have been little better than one of the lower animals. He was a nomad, wandering from place to place, feeding upon whatever living things he could kill with his hands. Gradually he must have learned to use weapons, and thus kill his prey, first using rough stone implements for this purpose. As man became more civilized, implements of bronze and of iron were used. About this time the subjugation and domestication of animals began to take place. Man then began to cultivate the fields, and to have a fixed place of abode other than a cave. the beginnings of civilaztion were long ago, but even to-day the earth is not entirely civilized.

The Races of man. --- At the present time there exist upon the earth five races or varieties of man, each very different from the other in instincts, social customs, and, to an extent, in structure. These are the Ethiopian or negro type, originating in Africa; the Malay or brown race, from the islands of the Pacific; the American Indian; the Mongolian or yellow race, including the natives of China, Japan, and the Eskimos; and finally, the highest type of all, the Caucasions, represented by the civilized white inhabitants of Europe and America....

Source: Excerpt from widely-used biology textbook, A Civic Biology, written in 1914 by George W. Hunter, a biology teacher from New York City.