Page:Creation by Evolution (1928).djvu/54

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CREATION BY EVOLUTION

would not all be purely transient, disappearing with the next generation; some of them would be hereditary; they would persist in later generations. The descendants of the original single individual would become diverse—hereditarily diverse. From a single individual, from a single race, we should thus, after the passage of many generations, get many races that would be hereditarily diverse.

In a human lifetime or in many human lifetimes we could not expect these changes to be great. Geological time is enormously long and evolution is prodigiously slow. The doctrine of evolution would therefore not lead us to expect to see widely diverse creatures produced. The popular demand that we should see a cat, or the offspring of a cat, transformed into a dog, or an amoeba into a vertebrate, is not in accord with the doctrine of evolution. We cannot expect in a lifetime to see new “species” produced. All that the doctrine of evolution leads us to expect is that there should appear slight hereditary changes, so that from a single race there are produced a number of hereditarily diverse races, differing slightly.

Do we find this? Studies of this sort have been made of a number of organisms. What was found in such a study made by the present writer may be set forth as a type.

It is common to suggest that amoeba or some amoeba-like creature is the original stock from which animals descended; “from amoeba to man” is a common phrase. It is of interest to examine amoebas from this point of view. Are amoebas still transforming, producing other kinds of animals? Some of the amoebas are naked and formless, so that the detection of any slight hereditary changes would be almost impossible. Others have shells of definite form and structure, furnishing excellent opportunity for the detection of hereditary alterations. These shelled amoebas, though they closely resemble

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