The chief question that we have to ask when we consider the changing status of women is: How will it affect the reproduction of the race? Hunger and love are the two great motor impulses, the ultimate source, probably, of all other impulses. 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 life everywhere. 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.[48] A 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. In civilized man, on the other hand, as we know him, the situation is to some extent reversed; it is the woman who, by the display of her attractions, competes for the favour of the man. The final invitation does not come, as among animals generally, from the female; the decision rests with the man. It would be a mistake to suppose that this change reveals the evolution of a superior method; although it has developed the beauty of women, it has clearly had its origin in economic causes. The demands of nutrition have overridden those of reproduction; sexual selection has, to a large extent, given place to natural selection, a process clearly not for the advantage of the race. The changing status of women, in bestowing economic independence, will certainly tend to restore to sexual selection its due weight in human development.