so long as it serves the race-process.
But men have set up a whole host of prohibitions and conventions--the
"thou shalt nots" of society and religion. Which are we to follow?
Which is the wheat and which the tares, that must be garnered or
sifted from our loves?

It is important to notice that among mammals, as among men, conjugal
fidelity is modified by the conditions of life. An animal belonging to
a species habitually monogamic may easily change under the pressure of
external causes and adopt polygamy, and, in some cases, polyandry. The
shoveler duck, though normally monogamic, is said[96] to practise
polyandry when males are in excess; two males being in constant and
amicable attendance on the female, without sign of jealousy.
Wild-ducks, again, which are strictly monogamous, good parents, and
very highly developed in social qualities when in a wild state, become
loosely polygamous and indifferent to their offspring under
domestication. Civilisation, in this case, depraves the birds, as
often it does men.

But enough has now been said. We shall find later how far the facts we
have learnt of the position of the female and the sexual relationship,
as we have studied them in these examples from the animal kingdom,
will apply to us and to our loves. We have now to study marriage and
the family as it exists among primitive peoples. We shall find a close
resemblance in the courtship customs and the sexual and familial
associations to those we have seen to be practised by our pre-human
ancestors. The same resemblance will persist when, lastly, we come to
investigate the same institutions among civilised races, up to our
own. Indeed, we may have to admit that, in some directions, love is
not even yet as finely developed with us humans as it is among birds.
It is in the loves of birds, as I believe, that we must seek hints to
that evolution in fineness, which has still to come in our love.

One thing more. It refers to the disputed question of the
differentiation of the sexes by the action of love's-selection. It is
a truth that I wish as strongly as I am able to emphasise. We cannot
learn to know love's selective powers by enclosing its action within
the narrow circle of our preconceived ideas. Instead of limiting its
power we should extend it without hindrance of any form--to the female
as well as the male; to the woman as to the man. We should regard
nothing as impossible, no development of either sex too great to be