ep
before the females are ready to pair, otherwise they might oscillate
between two modes of behaviour, created by the premature functioning of
conflicting impulses.

The different steps in the process seem to follow one another in ordered
sequence. The male inherits a disposition--which for us, of course, has
prospective meaning--to seek the appropriate breeding ground and there
to establish itself; and as early a functioning of this disposition as
possible, consonant with the conditions of existence in the external
environment, may have been evolved for the following reasons--firstly,
the earlier individuals will meet with less interference wherever they
may settle, every locality will be open to them, every acre free, their
only need being that particular environment for which racial preparation
has fitted them. In the second place, being already established when
other males appear upon the scene, and advertising their presence by
song, they will be less liable to molestation; thirdly, in those cases
in which a long journey is undertaken, they will have ample time to
recover from the fatigue, and, if attacked by later arrivals, will thus
be in a better position to defend their territories; and lastly, a
greater uniformity in their distribution will be insured before the
females begin their search.

There is, besides, another good reason for thinking that the earlier
males will have an advantage. We will assume--and from the abundant
evidence supplied by the marking of birds, it is quite a reasonable
assumption--that there is a tendency, generally speaking, for
individuals to return to the neighbourhood of their birthplace, or to
the place in which they had previously reared their offspring. Now the
earlier arrivals will have no difficulty in securing territories; those
that come later may have to search more diligently, still they will gain
all that they require so long as any available space remains. Then comes
the point when all suitable ground is occupied, and yet there are males
to be provided for. What will be the position of these males? Urged by
their inherited nature, they will leave the district and possibly
continue their search into those adjoining, only, however, to add to the
difficulties of the males there similarly situated; and even allowing
that they are at length successful in establishing themselves, what are
their prospects of securing mates? Since the earlier females will not
extend their wande