offspring is secured simply through the production of enormous numbers.
Thus the sturgeon, a low type of fish, produces between one and two
million of eggs at a single spawning, from which it is estimated that
not more than a dozen individuals survive till maturity is reached. Thus
sexual reproduction of itself necessitates no parental care and in
itself could give rise in no way to the family; but quite low in the
scale of life we begin to find some parental care as a device to protect
immature offspring and secure their survival without the expenditure of
such an enormous amount of energy in mere physiological reproduction.
Even among the fishes we find some that watch over the eggs after they
are spawned and care for their young by leading them to suitable feeding
grounds. In such cases a much smaller number of young need to be
produced in order that a few may survive until maturity is reached. In
the mammals the mother, obviously, must care for the young for some
time, since mammals are animals that suckle their young. But this care
of the young by a single parent only foreshadows the family as we
understand it. Among the mammals it is not until we reach the higher
types that we find care of offspring by both parents,--a practice,
however, which is common among the birds. It is evident that as soon as
both parents are concerned in the care of the offspring they have a much
better chance of survival. Hence, natural selection favors the growth of
this type of group life and develops powerful instincts to keep male and
female together till after the birth and rearing of offspring. Such we
find to be the condition among many of the higher mammals, such as some
of the carnivora, and especially among the monkeys and apes and man.

If it is allowable at this point to generalize from the facts given, it
must be said that the family life is essentially a device of nature for
the preservation of offspring through a more or less prolonged infancy.
The family group and the instincts upon which it rests were undoubtedly,