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Updated: May 16, 2025
How then can we rely upon use-inheritance for the improvement of the race?
I see no reason why use-inheritance need be credited with any share in the cumulative results of the invention of printing and the steam-engine and gunpowder, or of freedom and security under representative government, or of science and art and the partial emancipation of the mind of man from superstition, or of the innumerable other improvements or changes that take place under modern civilization.
Must we not feel, with Darwin apparently, that the only intelligible explanation of use-inheritance is the hypothesis of Pangenesis, according to which each modified cell, or physiological unit, throws off similarly-modified gemmules or parts of itself, which ultimately reproduce the change in offspring? If we reject pangenesis, it becomes difficult to see how use-inheritance can be possible.
Changed habits and the requisite change of structure will usually be favoured by natural selection; for habit, as Darwin says, "almost implies that some benefit great or small is thus derived." Here we perceive a difficulty which will equally trouble those who affirm use-inheritance and those who deny.
Is use-inheritance, then, only effective for evil? Does it only transfer the newly-acquired weakness, and not the previous long-continued vigour? Members of nervous families would be liable to suffer from nervous prostration, and by the ordinary law of heredity alone would transmit nervousness to their children.
The complete loss of the wings in neuter ants and termites can scarcely be due to the inherited effects of disuse; and as natural selection has abolished these wings in spite of the opposition of use-inheritance, it must clearly be fully competent to reduce wings without its aid.
But there happens to be a tolerably clear proof that such changes as the evolution of complicated structures and habits and social instincts can take place independently of use-inheritance. Working bees, being infertile "neuters," cannot as a rule transmit their own modifications and habits.
For the importance of panmixia as invalidating Darwin's strongest evidence for use-inheritance namely, that drawn from the effects of disuse in highly-fed domestic animals where there is supposed to be no economy of growth see Professor Romanes on Panmixia, Nature, April 3, 1890. Descent of Man, p. 33. Descent of Man, p. 33. Variation of Animals and Plants under Domestication, i., 453.
Of the latter kind, according to Darwin, there appears to be none a circumstance which contrasts strangely and suspiciously with the many decisive cases in which variation from unknown causes has been inherited most strikingly in the immediate offspring. It must be expected, indeed, that among these innumerable cases some will accidentally mimic the alleged effects of use-inheritance.
The benefits derivable from use-inheritance are largely illusory. The effects of use, indeed, are generally beneficial up to a certain point; for natural selection has sanctioned or evolved organs which possess the property or potentiality of developing to the right extent under the stimulus of use or nourishment.
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