The Act of Creation (68 page)

page 479
,
for instance, will show that
all
actual manifestations of the
reproductive instinct are classified as 'consummatory acts', whereas
'building', 'fighting', etc., are merely abstract, classificatory terms in
which longer sequences of consummatory acts are bracketed together. Where,
then, is the 'appetitive behaviour'? In the stickleback's spring
migration in search of a nesting site? But that action-pattern was,
judged by its dependence on specific releasers (temperature, verdant
vegetation, etc.) on the same 'consummatory' level as, for instance,
'testing of materials'. The nearest Tinbergen gets to a definition of
the consummatory act is in the following passage:

 

The activation of a centre of the lowest level usually, perhaps always,
results in a relatively simple motor response: biting, chasing,
threatening, etc., in the case of fighting. . . . actual eating,
actual escape, actual coition, etc., in other instincts. . . .
These relatively simple responses are, usually, the end of a bout
of prolonged activity, and their performance seems to "satisfy" the
animal, that is to say, to bring about a sudden drop of motivation.
This means that such an end-response consumes the specific impulses
responsible for its activation. Fighting, eating, mating, "playing
the broken wing" etc., are, as a rule, "self-exhausting". [23]

 

However, neither 'digging' nor 'leading female to nest' is
an end-response, or self-exhausting, or leads to a 'drop in
motivation'. 'Testing of materials' is not a consummation, but a
part-activity in the flexible, i.e. 'appetitive', pattern of building. And
the building activity is not a one-way affair in the sense of higher
levels in the hierarchy discharging along fixed conduits into the
lower level of consummatory acts, along irreversible gradients. On the
contrary, the control of operations oscillates all the time between
different levels; the operational units responsible for one kind of
'end-response' carry on until a centre on a higher level, informed by
feedback, switches to some other 'consummatory act'. It is at this point
that the concepts of 'hierarchies of environment' and 'hierarchies of
feedback' become important. In a complex activity like nest-building,
even the relatively stereotyped operations on subordinate levels are
under the dual control of their fixed codes and variable environment; and
furthermore, information about their activities is constantly fed back (by
proprioceptive and exteroceptive channels) to higher centres, so that the
whole always remains in hierarchic control 'through regulation channels'
of all of its parts. Tinbergen's schema does not really represent an
organismic hierarchy, but a mechanical one -- rather like an automatized
telephone net-work where the subscriber making a trunk call first dials
the code-number of the whole town ('appetitive behaviour'), then the code
of his fiancée's local exchange (semi-appetitive,
semi-consummatory?), and lastly her personal number (consummatory act).

 

 

Thorpe, arguing on similar lines, has given an inventory, which fills
two printed pages, of the eighteen releasers and fourteen distinct
action-patterns in the Longtailed Tits' 'consummatory acts' of building
a nest -- ending with the exclamation: 'So much for simplicity!' He
concludes:

 

It seems, then, that in much of appetitive behaviour the animal's own
activities . . . must be self-rewarding and self-stimulating. . . . In
other words, much appetitive behaviour is also in a sense the
consummatory act. . . . [24]  Hinde concludes that appetitive
behaviour and consummatory act differ only in degree, and that no
absolute distinction can be made between them. Both are to some extent
"spontaneous" in that they show evidence of external activation, and
both are stereotyped to some degree and show some rigidity. Thus the
classic examples of appetitive-behaviour and consummatory act can be
regarded as the two ends of a series ranging from extreme variability
and plasticity on the one hand to almost complete fixity on the
other. [25]

 

Many patterns of instinct-behaviour are of course cyclic:
hunting
---> capturing ---> ingesting ---> digesting ---> hunting
,
etc.; and all one can say about the sub-activities in the cycle is that
they are both 'appetitive' and 'consummatory', but that some are more
appetitive and some more consummatory than others.

 

 

What really matters in our context is the continuous scale of gradations
between rigid and flexible action-patterns. Somewhere near the middle of
the scale we find the common spider, whose web-making I have already used
as a paradigm for an invariant yet adaptable built-in code (Book One,
p. 38
). It will suspend its familiar net from three,
four, or more points of attachment, according to the lie of the land; yet
the centre of the polygonal web will always coincide with its centre of
gravity and the radial threads will always intersect the lateral threads
at equal angles. We thus have a simple fixed code, yet a highly flexible
strategy. Moreover, if some of the garden spider's legs and claws are
amputated, it will still construct a more or less normal net -- the code
remains unaffected by the elimination of some members of the matrix.

 

 

 

Leerlauf
and Displacement

 

 

Towards the 'rigid' end of the scale we find reflex-like matrices,
exemplified in the so-called
Leerlauf
activities. This term, too,
was coined by Lorenz; the current English translation is 'vacuum activity'
-- but 'freewheeling' would perhaps be more appropriate. Seagulls,
reared in isolation, will perform on the stone floor of the laboratory
their characteristic 'tap-dance' which, under normal circumstances,
would serve to bring small animals to the surface of the tidal mud. Cats
will go through the motion of burying their faeces on the kitchen tiles;
and hand-reared young flying-squirrels 'when given nuts, would go through
all the motions of burying them in the bottom of the wire-cage, and then
go away contented, even though the nuts were exposed to full view'. [26]
The same author describes the behaviour of hand-reared tawny owls 'which,
after being fed, would act as if pouncing upon living prey though it
had never had the experience of dealing with a living mouse'. [27]

 

 

Such examples of 'stupid', automaton-like behaviour are the strongest
evidence for innate codes of action. At the same time they are also
additional evidence against the chain-reflex theory of instinct-behaviour:
the owl, which has never seen a mouse, pounces
after
being fed,
and without any visual stimulus; in the gull's case, the hard floor
of the laboratory is a stimulus quite different from the soft mud --
hence the 'chain-reaction' ought never to start, or to break off after
the first unsuccessful attempt at 'digging' the tiles, Instincts are
purposive and flexible, but their flexibility is limited to conditions
more or less within the experience of the race. In a crassly unnatural
environment the performance degenerates into 'freewheeling' and loses
its purposive aspect.

 

 

According to Lorenz's rather controversial theory, the motivation of
Leerlauf
activity is derived from a 'damming up' of the animal's
'specific action potential' (SAP) which lowers the threshhold of the
innate releasing mechanism so that the action will go off even in the
absence of appropriate stimuli. Hence also the term 'overflow activity'.

 

 

Another distortion of instinct-behaviour are the so-called "displacement
activities" which overlap with
Leerlauf
(and also with play).
'Displacement is the performance of a behaviour pattern out of the
particular functional context of behaviour to which it is normally
related. It seems to appear when the charge (SAP) attached to one instinct
is denied opportunity for adequate discharge through its own consummatory
act or acts and instead
sparks over
to set going the comummatory
act of another instinct'. [28] A dog in its restraining harness in
a Pavlov-type laboratory, while expecting the fall of food from the
container, will stamp, yawn, and pant -- activities which do not belong
to his normal feeding behaviour; but what else, one may irreverently ask,
can the poor excited creature do? Pail-fed calves will suck the ears or
navels of their companions, as infants suck their thumbs. Some birds
play elaborate games, throwing up and catching sticks; so do puppies;
kittens will 'pretend' that a ball of wool is a mouse.
Leerlauf
and 'displacement' thus comprise a broad range of activities which occur
in the absence of the proper stimulus or in the presence of normally
inadequate ersatz stimuli; or when the proper response is for some
reason blocked. Its human equivalents range from playful activities to
repetition compulsions and the formation of neurotic ersatz symptoms.

 

 

 

Instinct and Originality

 

 

At the opposite end of the rigidity-flexibility scale we find adaptations
of instinct-based behaviour-patterns which give the impression of
original improvisation. Even the ritual-bound stickleback, that stickler
for etiquette, is capable of them: 'If the normal behaviour-pattern is
continually interfered with, quite large modifications in the normal
instinctive orientation of the nest-building movements may be made.' [29]

 

 

Thus the denial of normal outlets can lead either to the mechanical
reeling-off of the built-in pattern in freewheeling or displacement
activity; or to original re-adaptations of the pattern. Which of these
alternative possibilities will occur depends on the nature of the
challenge, and the animal's 'ripeness' to cope with it. What solution,
after all, could even a genius cat find to comply with its code of hygiene
on the kitchen tiles? What creative outlet is left to the squirrel to
solve his nut-hiding problem?

 

 

On the other hand, ethologists have produced many striking examples of
ingenious instinct-based behaviour in the face of adversity. The female
of a certain wasp,
Eumenes conica
, builds clusters of clay-cells
or pots, deposits an egg in each, provisions it with caterpillars for
food, then closes the cells with clay lids. If now an artificial hole is
made in a cell, the wasp will first stuff the caterpillars which have
fallen out back through the hole, then mend the hole with a pellet of
clay -- operations which are quite different from her normal building
routines. Hingston [30] has described in detail the actions of another
wasp --
Rhynchium nitiderium
-- in repairing a man-made hole in a
clay-pot. On one occasion the female tried for two hours to mend the hole
with bits of material taken from the wall of the pot. Then night came and
she had to give up. Next morning she flew straight to the damaged spot
and set about repairing it by a different strategy. In the normal course
of events the wasp works from outside. But now, in order to repair the
hole, 'she examines it from both sides and then, having made a choice,
elects to do the repair from within'. [31]

 

 

Equally surprising is the ingenuity, of the caddis-fly larva. If a
group of larvae are ejected from the tubular 'houses' which they built,
and are then allowed to return, they often get mixed up and enter the
wrong 'house' which is either too big or too small. The larva then sets
about to cut off parts of the tube or to add to it, until it fits it
exactly. Again the 'consummatory acts' in these activities are quite
different from those in normal building.

 

 

Many birds, too, are capable of such 'super-flexible' behaviour in
emergencies. If their brood is taken away, they will re-start their sexual
cycle, court and mate out of season, and get a new family going. In some
species, in the absence of the female, the male bird takes over her duties
in feeding the young -- which never happens under normal conditions.

 

 

Lastly, a brief mention must be made of 'supra-individual codes' --
such as those which regulate activities in the honey-bee hive. Lindauer,
among others, has shown that 'the programme of work carried out by the
individual is not determined by the physiological state of the insect but
is dictated by the needs of the colony as a whole'. [32] An individual
worker-bee hardly ever builds a complete cell. She may start the cell,
with wax from her own glands, then complete another cell, started by
a colleague, using her own wax or that of another bee -- whichever
happens to be convenient. Generally, there is rigid division of labour
according to age groups: each worker has to perform a different kind of
'National Service' in different periods of its life. During her first
three days, she works as a cell-cleaner. For the next three days she
feeds the older larvae with honey and pollen from the stores. Then she
feeds the younger larvae, who get an additional diet -- a liquid secreted
from glands on the worker's head. At the age of ten days she is engaged
in complex household chores and building activities. At twenty days she
takes over guard duties at the entrance of the hive; and finally, she
becomes a forager and remains one until the end of her life. But even
among the foragers there is further specialization of labour: some of
them become 'scouts', whose task it is to discover new sources of food,
and to communicate, on their return, the nature and location of it,
in their dance-language, to the hive. [33]

 

 

But this is not all. If one of the specialized age-groups is artificially
eliminated from the colony, a kind of collective super-flexibility
manifests itself in the hive: other age-groups deputize for the
vanished group 'and thus save the superorganism. When, for instance, all
pollen-and-honey foragers are taken away -- usually bees of twenty days or
over -- young bees of scarcely six days old, who normally feed the larvae,
fly out and become foragers. If all building workers are taken away --
those between eighteen and twenty days old -- their task is taken on by
older bees who had already been builders before, but who had gone on to
the stage of forager. To this end they not only change their behaviour,
but also regenerate the wax-glands. The mechanisms of these regulations
are not known.' [34]