THE UNIQUENESS OF MAN
man of one of his unique characteristics, whereby ho utilizes tradition
to the best advantage.
We have now dealt in a broad way with the unique properties of
man both from the comparative and the evolutionary point of view.
Now we can return to the present and the particular and discuss these
properties and their consequences a little more in detail. First, lot us
remind ourselves that the gap between human and animal thought
is much greater than is usually supposed. The tendency to project
familiar human qualities into animals is very strong, and colours the
ideas of nearly all people who have not special familiarity both with
animal behaviour and scientific method.
Let us recall a few cases illustrating the unhuman characteristics
of animal behaviour. Everyone is familiar with the rigidity of in-
stinct in insects. Worker ants emerge from their pupal case equipped
not with the instincts to care for ant grubs in general, but solely with
those suitable to ant grubs of their own species. They will attempt to
care for the grubs of other species, but appear incapable of learning
new methods if their instincts kill their foster children* Or again, a
worker wasp, without food for a hungry grub, has been known to bite
off its charge's tail and present it to its head. But even in the fine
flowers of vertebrate evolution, the birds and mammals, behaviour,
though it may be more plastic than in the insects, is as essentially
irrational. Birds, for instance, seem incapable of analysing un-
familiar situations. For them some element in the situation may act
as its dominant symbol, the only stimulus to which they can react.
At other times, it is the organization of the situation as a whole which
is the stimulus: if the whole is interfered with, analysis fails to dissect
out the essential element. A hen meadow-pipit feeds her young when
it gapes and squeaks in the nest. But if it has been ejected by a young
cuckoo, gaping and squeaking has no effect, and the rightful offspring
is neglected and allowed to die, while the usurper in the nest is fed.
The pipit normally cares for its own young, but not because it
recognizes them as such.
Mammals are no better. A cow deprived of its calf will be quieted
by the provision of a crudely stuffed calf-skin. Even, the Primates are
no exception. Female baboons whose offspring have died will con-
tinue carrying the corpses until they have not merely putrefied but
mummified. This appears to be due not to any profundity of grief,
but to a contact stimulus: the mother will react similarly to any
moderately small and furry object.
Birds and especially mammals are, of course, capable of a certain
degree of analysis, but this is effected, in the main, by means of trial