Page:George Archdall Reid 1896 The present evolution of man.djvu/31

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ORGANIC EVOLUTION—PHYSICAL
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they do any other given individual. For instance, if before a child is born we indicate any individual of our acquaintance, the chances are immensely greater that the child when grown will resemble a particular ancestor than that he will resemble the person indicated. That is to say, there is a greater tendency for the child to vary from its parents in the direction of its ancestry than in any other given direction. Now if the parent has varied from the grandparent in any other direction than towards the ancestry, this, the child's variation towards the ancestry, is evidently an omission of the last step made in the evolution of the race. It is what is known as atavism[1] and is sometimes carried so far that the variations (i.e. the evolution) of hundreds of ancestors nearest it are omitted, and the child resembles some extremely remote ancestor, being ape-like in features, especially in times of famine, when want of nourishment checks the development, and sometimes being covered with long hair. So also the progeny of a pair of thoroughbred horses is sometimes an "arrant weed," or it may revert to an even more remote ancestor, by showing zebra-like stripes. So also "a blue pigeon, like the ancient Columba Livia, may be hatched in the dovecot." On the other hand, the progeny of a pair of ordinary horses never has the peculiar characteristics of the racer; nor has the progeny of a blue pigeon ever those of the pouter or fantail.

It is well known that race-horses have been developed by an extremely stringent process of artificial selection. I believe I am right in saying that when this process

  1. 'Atavism, which is the name given to the recurrence of ancestral traits, is proved by many and varied facts. In the picture-galleries of old families, and on the monumental brasses in adjacent churches, are often seen types of feature that are still, from time to time, repeated in members of their families."—Herbert Spencer's Principles of Biology, vol, i. p. 252.