- Hunger—that is to say, what we call "economic causes"—has, because it is the more widespread and constant, though not necessarily the more imperious instinct, produced nearly all the great zoological revolutions, including, as we have seen, the rise and fall of that phase of human evolution dominated by mother-law. * Yet love has, in the form of sexual selection, even before we reach the vertebrates, moulded races to the ideal of the female; and reproduction is always the chief end of nutrition which hunger waits on, the supreme aim of
If we place on the one side man, as we know him during the historical period, and on the other, nearly every highly organized member of the animal family, there appears, speaking roughly and generally, a distinct difference in the relation which these two motor impulses bear to each other.
Among animals generally, economics are comparatively so simple that it is possible to satisfy the nutritive instinct without putting any hard pressure on the spontaneous play of the reproductive instinct. And nearly everywhere it is the female who has the chief voice in the establishment of sexual relationships.
The males compete for the favour of the female by the fascination of their odour, or brilliant colour, or song, or grace, or strength, as revealed in what are usually mock-combats. The female is, in these respects, comparatively unaccomplished and comparatively passive. With her rests the final decision, and only after long hesitation, influenced, it seems, by a vaguely felt ideal resulting from her contemplation of the rivals, she calls the male of her choice.
3A dim instinct seems to warn her of the pains and cares of maternity, so that only the largest promises of pleasure can induce her to undertake the function of reproduction.