[25] Ibid. p. 576.
[26] Ibid. pp. 458, 459.
[27] Ibid. p. 574.
[28] Ibid. p. 234.
CHAPTER II.
MARRIAGE AND THE FAMILY AMONGST ANIMALS.
I. The preservation of species.—Two great processes of preservation—Different rôles of the male and the female in the animal family.
II. Marriage and the rearing of the young among animals.—Abandonment of the young in the inferior species—The superior molluscs guard their eggs—Solicitude of spiders for their eggs and their young—Instinctive foresight of insects—Its origin—Larvæ are ancestral forms—The familial instinct amongst birds—Frequency of monogamy amongst birds.
III. The family amongst animals.—Intoxication of egg-laying with birds—Absence of paternal love in certain birds—The familial instinct very developed in certain species—Transient nature of their love for the young—Promiscuity, polygamy, and monogamy among mammals—Hordes of sociable animals—Polygamous monkeys—Monogamous monkeys—General observations.
I. The Preservation of Species.
Two great processes are employed in the animal kingdom to assure the preservation of the species: either the parents do not concern themselves at all with their progeny, in which case the females give birth to an enormous number of young; or, on the other hand, they are full of solicitude for their offspring, cherishing and protecting them against the numerous dangers that menace them; and, in this last case, the young are few in number. Nature (since the expression is consecrated) proceeds sometimes by a lavish and lawless production, and sometimes by a sort of Malthusianism. Thus a cod lays every year about a million eggs, on which she bestows no care, and of which only the thousandth, or perhaps even the hundred thousandth part, escapes destruction; turtle-doves, on the contrary, only lay two eggs, but nearly all their young attain maturity. In short, the species is maintained sometimes by prodigality of births and sometimes by a great expenditure of care and affection on the part of the parents, especially of the female. It is almost superfluous to remark that analogous facts are observed in human natality, according as it is savage or civilised.