Descending in the scale of Nature to the lowest forms of animal life, we observe that the young are left to hatch and develop without maternal or paternal love or protection; in fact, it is doubtful if there is such a thing as love in animals lower in the scale than mammals anc1. birds. "What does exist, and sometimes in marvellous perfection, is care for eggs: but that is a wholly different thing, both in its physical and psychical aspect, from love of offspring. The truth is, Nature so made animals in the early days that they did not need mothers. The moment they were born they looked after themselves, and were perfectly able to look after themselves".
The young of the lower forms of life are so multitudinous that, were they all to develop, the earth and sea would be filled with teeming millions of them; but only a few of the fortunate ones reach maturity, all of them being entirely dependent on themselves from the moment of birth. It is only when we reach the higher forms of life that the mothers even recognize their young, and for this purpose it is necessary that the offspring shall be few in number, similar in appearance to their parents, and dependent, on account of their helplessness, on their mothers. Such is the case with the Mammalia, in contradistinction, for instance, to the reptiles and batrachians and fish, with their innumerable progeny.
In the lower forms of animal life the maternal care is limited to the depositing of the eggs in a safe place, the young being left without parental assistance to hatch by chanee and to provide for themselves from the outset. Parental affection is entirely wanting, since the early stages do not resemble the mature stages, and since the mothers often die soon after they have deposited the eggs.
It is not until we ascend in the scale of life to the birds that we find this love and domestic happiness, and here, except among the fowls and barnyard poultry, we find the most intimate and lasting marriages; and Dr. Brehm1 says: "Eeal genuine marriage can only be found among birds".
"In birds parental affection has reached a very high degree of development, not only on the mother's side, but also on the father's. Male and female help each other to build the nest, the former generally bringing the materials, the latter doing the work. In fulfilling the numberless duties of the breeding season, both birds take a share. Incubation rests principally with the mother, but the father, as a rule, helps his companion, taking her place when she wants to leave the nest for a moment, or providing her with food and protecting her from every danger.
Finally, when the duties of the breeding season are over, and the result desired is obtained, a period with new duties commences. During the first few days after hatching, most birds rarely leave their young for long, and then only to procure food for themselves and their family. In cases of great danger, both parents bravely defend their offspring. As soon as the first period of helplessness is over, and the young have grown somewhat, they are carefully taught to shift for themselves; and it is only when they are perfectly capable of so doing that they leave the nest and the parents. "With the advance to the Mammalia, mothers made an immense step forward through the very fact that their young are more dependent, take longer to develop, and that they must stay close to the parent.
The young seeks its mother's teats to derive nourishment, and the mother is no less dependent on it to relieve her breasts of engorgement. In this way an inexpressibly powerful affection and endearment grows up between the two, which is the stronger in proportion to the fewness of the offspring and the length of the time of dependency. Such a mother will start at the slightest cry of pain from her child; and if danger threaten, a maternal fury is exhibited which none can ignore with impunity.
Of all the animals none is so tardy in its development nor so utterly helpless in its feebleness as the human babe. A kitten, a calf, or a colt, or a baby monkey, at six months of age knows immeasurably more and is entirely independent of care; but the infant, even at a much later date than that, is absolutely helpless and dependent for its every want.