[Source description: Gilbert Haven Trafton, Biology of Home and Community: A Textbook for High Schools. New York: Macmillan, 1923, pp. 579-580. About this source.]
Main problem. What are the chief reasons for believing in evolution, and how has evolution been brought about?
I. MEANING OF EVOLUTION
Many people have a wrong notion as to what evolution means; and as you may have heard some of these people talk who have this misconception, it will be well at the very beginning of the chapter to explain what the word really means so that there will be no misunderstanding as you read the rest of the chapter.
Evolution means that the various species of plants and animals now found on the earth have descended from other plants and animals, and these in turn from still others; and if these could be traced back far enough, it would be found that these all came originally from one common ancestral species, which was a very simple form of life. Or, to put it in another way, the first form of life that appeared on this earth many millions of years ago was a very simple form, and from that form have gradually evolved all the varied and complex forms of life that we find today. How long this has taken no one knows, but the time must probably be reckoned in millions, perhaps hundred of millions, of years. Looking toward the future, evolution means that animals and plants will continue to go on changing and that thousands of years in the future they will be different from what they are now. In short, evolution means change, natural and orderly change.
One erroneous notion which some people have about evolution is that it means that man has descended from the monkey. What it really means is that if we could trace back far enough through thousands of years the ancestry of man and monkey, it would be found that they came from the same ancestor, an animal different from any now living. Man is related to the monkey but did not descend from one. The relationship is much like two twigs on a tree that come out of a common branch like a letter Y. One twig does not grow from the other but they both grow from the same branch. Or, to put it in still another way, man and monkey are like cousins in that they had a common ancestor.
About this Source: Biology of Home and Community was one of the two textbooks originally approved by the North Carolina Text Book Commission, but later rejected by the State Board of Education after Governor Cameron Morrison spoke out against the two texts, criticizing them for their treatment of evolution.