ken in response to some inherited disposition,
and probable also that the disposition bears some relation to the few
acres in which the bird ultimately finds a resting place. Whilst for the
purpose of the theory I shall give expression to this behaviour in terms
of that theory, and speak of it as a disposition to secure a territory,
using the word disposition, which has been rendered current in recent
discussion, for that part of the inherited nature which has been
organised to subserve a specific biological purpose--strict compliance
with the rules of psychological analysis requires a simpler definition;
let us therefore say "disposition to remain in a particular place in a
particular environment."

But even granting that this disposition forms part of the hereditary
equipment of the bird, how is the process of reproduction furthered? The
mere fact of remaining in or about a particular spot cannot render the
attainment of reproduction any less arduous, and may indeed add to the
difficulties, for any number of individuals might congregate together
and mutually affect one another's interests. A second disposition comes,
however, into functional activity at much the same stage of sexual
development, and manifests itself in the male's intolerance of other
individuals. And the two combined open up an avenue through which the
individual can approach the goal of reproduction. In terms of the theory
I shall refer to this second disposition as the one which is concerned
with the defence of the territory.

Broadly speaking, these two dispositions may be regarded as the basis
upon which the breeding territory is founded. Yet inasmuch as the
survival value of the dispositions themselves must have depended upon
the success of the process as a whole, it is manifest that peculiar
significance must not be attached to just the area occupied, which
happens to be so susceptible of observation; other contributory factors
must also receive attention, for the process is but an order of
relationships in which the various units have each had their share in
determining the nature and course of subsequent process, so that, as Dr
Stout says, when they were modified, it was modified.

Now the male inherits a disposition which leads it to remain in a
restricted area, but the disposition cannot determine the extent of that
area. How then are the boundaries fixed? That they are sometimes adhered
to with remarkable precision, that they can only be