apse, the warmth
from the body of the brooding bird was sufficient to restore them
temporarily; once more they would become lively and responsive, only,
however, to revert to the previous condition soon after the parent had
again abandoned them. Doubtless their power of resistance grew less and
less during each successive period of exposure.

If the nestling Bunting is to be freed from the risk of exposure, it is
evident that there must be, in the vicinity of the nest, an adequate
supply of food upon which the parents can draw liberally. Hence those
pairs that exercise dominion over the few acres surrounding the nest,
and are thus able to obtain food rapidly, will stand a better chance of
rearing their offspring than others which have no certain supply to draw
upon--and this, I believe, is one of the biological ends for which the
territory has been evolved. But it must not be supposed that each pair
finds, or even attempts to find, the whole of the food within its
territory, or that it is necessary for the theory that it should do so;
all that is required is that such overcrowding as might lead to
prolonged absence on the part of the parents and inordinate exposure of
the young shall be avoided. So that the problem has to be considered not
merely from the point of view of the individual, but from the larger
point of view of all the pairs inhabiting a given area.

Now there were eight pairs of Yellow Buntings occupying the one corner
of Hartlebury Common, and their territories in the aggregate covered
some fifteen acres. The birds obtained part of their food-supply amongst
the gorse and in some young scattered oak-trees, and part in an
adjoining coppice and on the surrounding arable land. But they were not
the sole occupants of this corner of the Common; other insectivorous
species had territories there also--amongst which were Whitethroats,
Grasshopper-Warblers, Willow-Warblers, Whinchats, Stonechats,
Meadow-Pipits, Tree-Pipits, and Skylarks. Suppose then that there had
been sixteen pairs of Yellow Buntings instead of eight; that there had
been other pairs, which assuredly there were, inhabiting the locality;
that they had also resorted, which assuredly they did, to the coppice
and arable ground for the purpose of securing food; and that their
numbers had also been increased in a similar ratio--would a supply of
food for all have been forthcoming with the necessary regularity and
promptitude? Well, the parents might ha