Page:The British Warblers A History with Problems of Their Lives - 7 of 9.djvu/31

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MARSH WARBLER

in which sexual passion is psychologically sublimated into love. According to this theory, there is choice only in the sense that the hare finally succumbs to the best hound, which is as much as to say that the phenomena of courtship are referred at once to natural selection. It follows, too, that however useful attractive form and colouring may be in relation to other ends, they certainly contribute to that of subduing feminine coyness, and hence further the sexual life." And Professor Lloyd Morgan comes to the conclusion that[1]: "stripped of all its unnecessary æsthetic surplusage, at any rate so far as this implies an aesthetic ideal, or aesthetic motive, the hypothesis of sexual selection suggests that the accepted mate is the one which adequately evokes the pairing impulse." These opinions differ widely from the original theory of sexual selection, but even this modified form is not altogether free from criticism, as I shall endeavour to show in connection with the phenomena which we are now discussing. Since conscious display is discarded, the theory becomes, primarily, one of the development of emotion. It is assumed that the strength of the species is represented by the strength of its emotion, that the strength of the emotion is reflected in the intensity of the expression—that is to say in the movements, which are peculiarly attractive to the female, of the limbs and body of the male—and finally that inasmuch as the strength of different individuals is a variable quantity, so, at the other extreme, the capacity for movement will vary correspondingly, becoming consequently an index of the fitness of the individual to take its share in reproduction. Now this seems to me to be taking a great deal for granted. When we speak of a species being emotional all we mean to imply is that the visible expressional movement is well marked. Of internal organic changes we know nothing, though we believe that they too must be present and play an important part in the total emotional complex. In human emotion the expressional


  1. "Animal Behaviour," p. 264.

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