Within recent years much attention has been given to the diminishing number of births per 1,000 of population, but only rarely has it been recognized as a phenomenon which has been going on since prehistory, and even before that in the prehuman stage. Discussion of the matter has raised apprehensions for the future, which are ridiculous in view of the fact that no harm can possibly result from a beneficial process found in all animals. There are so many elements in this phenomenon that it is really a most complicated matter.
The first point to notice is the decreasing number of births per marriage. The question naturally arises in everyone's mind that if the people were always so crowded why did not the birth rate lessen in accordance with the same biological law under which certain sea birds have been reduced to only one egg a year. By survival of the fittest, other things being equal, the birds having the fewest offspring a year were better able to rear them, the others being so overburdened that the young suffered in nourishment. The advantage was with the small families. This same law must exist in man's case. It is a fact that the smaller families of a modern civilized people have better care and possess the advantage in the struggle for family survival. In primitive civilization, the man who happened to have a small number of children was better able to raise them than he with fifteen or twenty, and such families have survived in greater proportions and have tended to the evolution of the modern small family. This can be accounted for as a natural selection of an accidental variation in fecundity. Whatever its cause we certainly do know that the further a nation is advanced in civilization the smaller are the families. In each Filipino family there are fifteen to twenty births even yet, but among the Anglo-Saxons it is about five. Of the number born, the Filipino raises very few indeed, but in England and Wales the families average about four surviving children, and the higher classes are said to average three in both America and England. When there are large families among civilized peoples, fifteen to twenty children, the parents generally show strong evidences of abnormality. It is not necessarily atavistic, a reversion to savage type, but it is recognized as a stigma of degeneration as much as sterility. The rule for the normal civilized man is fewer births and more of them raised to maturity.*
The diminution of births must have been exceedingly slow at first, because the savage man does not need to care for the children very long. After the child is weaned it is virtually turned adrift, and by the time the next infant is born the elder receives but little attention. It is allowed to live at home until it is able to do something toward the support of the family. Indeed, the little tots are put to use so soon that they are an actual advantage. In Filipino and Japanese families the babies seem to be cared for exclusively by the boys and girls from eight to twelve years old. So that in primitive times there was such a slight advantage to a small family, if any, that marked reduction did not commence until quite a high civilization was reached.
* These laws are seen in a general way in the following table of annual births, per 1,000, of population:
The fecundity of the different races in the United States is said to be in the following order, and inclines to the same rule:
Bohemian Russian Hungarian Italian.
Scandinavian Canadian English.
To be able to look after itself soon, the savage child has been under natural selection in that it matures very early - boys become men at sixteen to eighteen, and girls are women at thirteen to fifteen; all able to take up the burdens of life. In civilized life the law has worked the other way, and those children who received the most care survived, and this has resulted in prolonging the period of immaturity, so that children must be cared for during many years. Hence, the rule that the higher the race, the more are its necessities of existence; that is, the more does each individual need for survival. If several children are in a civilized family all must be looked after. Suppose there are five, an infant, one each of two. four, six and eight years. This is an excessive burden for one woman. The woman of lower races looks after the infant a little, and compels the two eldest to care for the rest. Is it strange, then, that there should be a natural decrease in births from survival of those who naturally had small families? How much better off than the above for the purposes of prolonging our species, is the civilized woman who has three children, several years apart. They are all so much better cared for that they are better nourished, and become better men and women. That is, she raises more of them if she has few.
Hence, the birth rates have been decreasing for a long time, at first slowly but with ever-increasing rapidity. It became noticeable at the end of the nineteenth century, but the people have just learned of it and become unnecessarily worried. In 1878 the rate in the United Kingdom was thirty-five and nine tenths per 1,000 of population: thirty-two and five tenths in 1888; twenty-nine and eight tenths in 1898, and in 1908 about twenty-six. This is a tremendous change from the estimated rate of 200 among primitive men, when each woman had a child every year, when there were no old people, and but few surviving children to each couple.*