masters in this country receive much less service from their slaves
than they do in Switzerland.
By what steps the instinct of F. sanguinea originated I will not
pretend to conjecture. But as ants, which are not slave-makers, will,
as I have seen, carry off pup of other species, if scattered near
their nests, it is possible that pup originally stored as food might
become developed; and the ants thus unintentionally reared would then
follow their proper instincts, and do what work they could. If their
presence proved useful to the species which had seized them if it were
more advantageous
to this species to capture workers than to procreate them the habit of
collecting pup originally for food might by natural selection be
strengthened and rendered permanent for the very different purpose of
raising slaves. When the instinct was once acquired, if carried out to
a much less extent even than in our British F. sanguinea, which, as we
have seen, is less aided by its slaves than the same species in
Switzerland, I can see no difficulty in natural selection increasing
and modifying the instinct always supposing each modification to be of
use to the species until an ant was formed as abjectly dependent on its
slaves as is the Formica rufescens.
_Cell-making instinct of the Hive-Bee_. I will not here enter on minute
details on this subject, but will merely give an outline of the
conclusions at which I have arrived. He must be a dull man who can
examine the exquisite structure of a comb, so beautifully adapted to
its end, without enthusiastic admiration. We hear from mathematicians
that bees have practically solved a recondite problem, and have made
their cells of the proper shape to hold the greatest possible amount of
honey, with the least possible consumption of precious wax in their
construction. It has been remarked that a skilful workman, with fitting
tools and measures, would find it very difficult to make cells of wax
of the true form, though this is perfectly effected by a crowd of bees
working in a dark hive. Grant whatever instincts you please, and it
seems at first quite inconceivable how they can make all the necessary
angles and planes, or even perceive when they are correctly made. But
the difficulty is not nearly so great as it at first appears: all this
beautiful work can be shown, I think, to follow from a few very simple
instincts.
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