Among animals the choice of mates is largely determined by the females. In fact, among the lowest types of animals there are no males. Among certain higher forms of animal life the male appears as a mere adjunct. But among human beings, male sexual selection developed. This change in sexual selection is one of the differences between the brute and the human worlds. This transition is explained by the fact that the higher a being rises in the scale of development the more sensitive its organs become, and by the correlated fact that the male human being through his reason is able to arouse and satisfy a thousand desires within the female, and thus cause her to look to him for “that protection and those favors which he alone can confer.”[XVII-28] In the human world the reproductive forces have first produced a crude sexual love, animal in its nature, but far-reaching in its basic implications. Sexual love is an unconscious but dominant factor in courtship. In its refined form, and modified by the addition of genuine but often short-lived affective elements, it becomes romantic love. Romantic love, according to Ward, unfits lovers for the normal pursuits of life. While under its spell they are unable to enjoy anything but each other’s presence. “The man is unfitted for business, the woman for social life, and both for intellectual pursuits. The only spur that can make either party pursue other things, is the sense of doing something that the other desires.”[XVII-29] In the sense that natural, or sexual, love becomes the basis of romantic love, so romantic love in turn represents the genesis of a still higher form of love, namely, conjugal love. The love of a man for his wife or of a woman for her husband is, however, fundamentally different from romantic love. It is more stable, less disturbing to the normal processes of life, and makes the home and the family socially productive institutions. It often reaches a high state of refinement and develops its beauty of content from the sharing together by husband and wife of great joys and sorrows. Maternal love, an outgrowth of maternity, manifests startling degrees of courage even among animals. Under the spur of the need for defending her young, a mother will often perform miraculous deeds. In its highest form maternal love manifests a remarkable strength throughout life and an extra-human power of forgiveness. Then there is consanguineal love, which according to Ward includes paternal and fraternal affections. It becomes the blood bond or feeling of attachment that exists among the members of a primitive kinship group, and it leads to feelings of race and world solidarity and attachment.