BRITISH WARBLERS
instance: The male Blackcaps, when excited with one another, or with another species, such as Sylvia hortensis, assume the same positions as when courting the females. To what do these facts point? Certainly not to a conscious display.
Further evidence, details of which I need not enter into here, prove that all these actions are intimately associated with the development and stimulation of the sexual organs.
When we come to consider all these facts, when, on the one hand, we find evidence of so strong a character opposed to the theory of sexual selection, and on the other, find that actions similar in every respect are frequently performed at other periods of great excitement in a bird's life, can we doubt the probability of their being solely reflex in kind?[1] I think not. All the difficulties would thus be removed, the second courtship of the Sedge-Warbler— a courtship which, although I have not hitherto seen it, yet in my opinion undoubtedly occurs amongst other species—is explained; and there would only remain the general argument, namely, that it is impossible to believe that all the trouble which many species apparently take with their courtship is purposeless: and this argument may be raised against the theory of reflex action; but because I exclude conscious choice from being in any way directly responsible for these actions. I by no means wish to imply that they are purposeless, neither am I prepared to enter into further explanation here, for I hold that with the very meagre knowledge that we, even at the present day, possess of all the facts relating to this most interesting subject, it would be unwise to attempt to formulate a theory in explanation of their ultimate purpose.
The peculiar manner in which these birds walk along
- ↑ In his "Last Words on Evolution," Professor Ernst Haeckel considers "sexual selection" of the greatest importance, both for the general theory of evolution and also for psychology, anthropology, and æsthetics. Since the importance of it is so great, no labour, surely, ought to have been spared to have verified the completeness of the fundamental evidence upon which it was originally based?
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