The Outline of Science, Vol. 1 (of 4)

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Intelligence co-operating with Instinct

Professor Lloyd Morgan was foster-parent to two moorhens which grew up
in isolation from their kindred. They swam instinctively, but they would
not dive, neither in a large bath nor in a current. But it happened one
day when one of these moorhens was swimming in a pool on a Yorkshire
stream, that a puppy came barking down the bank and made an awkward
feint towards the young bird. In a moment the moorhen dived, disappeared
from view, and soon partially reappeared, his head just peeping above
the water beneath the overhanging bank. This was the first time the bird
had dived, and the performance was absolutely true to type.

There can be little doubt as to the meaning of this observation. The
moorhen has an hereditary or instinctive capacity for swimming and
diving, but the latter is not so easily called into activity as the
former. The particular moorhen in question had enjoyed about two months
of swimming experience, which probably counted for something, but in the
course of that experience nothing had pulled the trigger of the diving
capacity. On an eventful day the young moorhen saw and heard the dog; it
was emotionally excited; it probably did to some extent intelligently
appreciate a novel and meaningful situation. Intelligence cooperated
with instinct, and the bird dived appropriately.

Birds have inborn predispositions to certain effective ways of pecking,
scratching, swimming, diving, flying, crouching, lying low,
nest-building, and so on; but they are marked off from the much more
purely instinctive ants and bees by the extent to which individual
"nurture" seems to mingle with the inherited "nature." The two together
result in the fine product which we call the bird's behaviour. After
Lloyd Morgan's chicks had tried a few conspicuous and unpalatable
caterpillars, they had no use for any more. They learned in their early
days with prodigious rapidity, illustrating the deep difference between
the "big-brain" type, relatively poor in its endowment of instinctive
capacities, but eminently "educable," and the "little-brain" type, say,
of ants and bees, richly endowed with instinctive capacities, but very
far from being quick or glad to learn. We owe it to Sir Ray Lankester to
have made it clear that these two types of brain are, as it were, on
different tacks of evolution, and should not be directly pitted against
one another. The "little-brain" type makes for a climax in the ant,
where instinctive behaviour reaches a high degree of perfection; the
"big-brain" type reaches its climax in horse and dog, in elephant and
monkey. The particular interest that attaches to the behaviour of birds
is in the combination of a good deal of instinct with a great deal of
intelligent learning. This is well illustrated when birds make a nest
out of new materials or in some quite novel situation. It is clearly
seen when birds turn to some new kind of food, like the Kea parrot,
which attacks the sheep in New Zealand.

Some young woodpeckers are quite clever in opening fir cones to get at
the seeds, and this might be hastily referred to a well-defined
hereditary capacity. But the facts are that the parents bring their
young ones first the seeds themselves, then partly opened cones, and
then intact ones. There is an educative process, and so it is in scores
of cases.

Using their Wits

When the Greek eagle lifts the Greek tortoise in its talons, and lets it
fall from a height so that the strong carapace is broken and the flesh
exposed, it is making intelligent use of an expedient. Whether it
discovered the expedient by experimenting, as is possible, or by chance,
as is more likely, it uses it intelligently. In the same way
herring-gulls lift sea-urchins and clams in their bills, and let them
fall on the rocks so that the shells are broken. In the same way rooks
deal with freshwater mussels.

The Thrush's Anvil

A very instructive case is the behaviour of the song-thrush when it
takes a wood-snail in its beak and hammers it against a stone, its
so-called anvil. To a young thrush, which she had brought up by hand,
Miss Frances Pitt offered some wood-snails, but it took no interest in
them until one put out its head and began to move about. The bird then
pecked at the snail's horns, but was evidently puzzled when the creature
retreated within the shelter of the shell. This happened over and over
again, the thrush's inquisitive interest increasing day by day. It
pecked at the shell and even picked it up by the lip, but no real
progress was made till the sixth day, when the thrush seized the snail
and beat it on the ground as it would a big worm. On the same day it
picked up a shell and knocked it repeatedly against a stone, trying
first one snail and then another. After fifteen minutes' hard work, the
thrush managed to break one, and after that it was all easy. A certain
predisposition to beat things on the ground was doubtless present, but
the experiment showed that the use of an anvil could be arrived at by an
untutored bird. After prolonged trying it found out how to deal with a
difficult situation. It may be said that in more natural conditions this
might be picked up by imitation, but while this is quite possible, it is
useful to notice that experiments with animals lead us to doubt whether
imitation counts for nearly so much as used to be believed.

Sec. 6

The Mind of the Mammal

When we watch a collie at a sheep-driving competition, or an elephant
helping the forester, or a horse shunting waggons at a railway siding,
we are apt to be too generous to the mammal mind. For in the cases we
have just mentioned, part of man's mind has, so to speak, got into the
animal's. On the other hand, when we study rabbits and guinea-pigs, we
are apt to be too stingy, for these rodents are under the average of
mammals, and those that live in domestication illustrate the stupefying
effect of a too sheltered life. The same applies to domesticated sheep
contrasted with wild sheep, or even with their own lambs. If we are to
form a sound judgment on the intelligence of mammals we must not attend
too much to those that have profited by man's training, nor to those
whose mental life has been dulled by domestication.

Instinctive Aptitudes

What is to be said of the behaviour of beavers who gnaw the base of a
tree with their chisel-edged teeth till only a narrow core is left--to
snap in the first gale, bringing the useful branches down to the ground?
What is to be said of the harvest-mouse constructing its nest, or of the
squirrel making cache after cache of nuts? These and many similar pieces
of behaviour are fundamentally instinctive, due to inborn
predispositions of nerve-cells and muscle-cells. But in mammals they
seem to be often attended by a certain amount of intelligent attention,
saving the creature from the tyranny of routine so marked in the ways of
ants and bees.

Sheer Dexterity

Besides instinctive aptitudes, which are exhibited in almost equal
perfection by all the members of the same species, there are acquired
dexterities which depend on individual opportunities. They are also
marked by being outside and beyond ordinary routine--not that any
rigorous boundary line can be drawn. We read that at Mathura on the
Jumna doles of food are provided by the piety of pilgrims for the sacred
river-tortoises, which are so crowded when there is food going that
their smooth carapaces form a more or less continuous raft across the
river. On that unsteady slippery bridge the Langur monkeys
(_Semnopithecus entellus_) venture out and in spite of vicious snaps
secure a share of the booty. This picture of the monkeys securing a
footing on the moving mass of turtle-backs is almost a diagram of sheer
dexterity. It illustrates the spirit of adventure, the will to
experiment, which is, we believe, the main motive-force in new
departures in behaviour.

[Illustration: _Photo: Lafayette_

ALSATIAN WOLF-DOG

An animal of acute senses and great intelligence. It was of great
service in the war.

(The dog shown, Arno von Indetal, is a trained police dog and did
service abroad during the war.)]

[Illustration: _Photo: W. S. Berridge._

THE POLAR BEAR OF THE FAR NORTH

An animal of extraordinary strength, able with a stroke of its paw to
lift a big seal right out of the water and send it crashing along the
ice. The food consists chiefly of seals. The sexes wander separately. A
hole is often dug as a winter retreat, but there is no hibernation. A
polar bear in captivity has been seen making a current with its paw in
the water of its pool in order to secure floating buns without
trouble--an instance of sheer intelligence.]

[Illustration: _From the Smithsonian Report_, 1914

AN ALLIGATOR "YAWNING" IN EXPECTATION OF FOOD

Note the large number of sharp conical teeth fixed in sockets along the
jaws.]

Power of Association

A bull-terrier called Jasper, studied by Prof. J. B. Watson, showed
great power of associating certain words with certain actions. From a
position invisible to the dog the owner would give certain commands,
such as "Go into the next room and bring me a paper lying on the floor."
Jasper did this at once, and a score of similar things.

Lord Avebury's dog Van was accustomed to go to a box containing a small
number of printed cards and select the card TEA or OUT, as the occasion
suggested. It had established an association between certain black marks
on a white background and the gratification of certain desires. It is
probable that some of the extraordinary things horses and dogs have been
known to do in the way of stamping a certain number of times in supposed
indication of an answer to an arithmetical question (in the case of
horses), or of the name of an object drawn (in the case of dogs), are
dependent on clever associations established by the teacher between
minute signs and a number of stampings. What is certain is that mammals
have in varying degrees a strong power of establishing associations.
There is often some delicacy in the association established. Everyone
knows of cases where a dog, a cat, or a horse will remain quite
uninterested, to all appearance, in its owner's movements until some
little detail, such as taking a key from its peg, pulls the trigger. Now
the importance of this in the wild life of the fox or the hare, the
otter or the squirrel, is obviously that the young animals learn to
associate certain sounds in their environment with definite
possibilities. They have to learn an alphabet of woodcraft, the letters
of which are chiefly sounds and scents.

The Dancing Mouse as a Pupil

The dancing or waltzing mouse is a Japanese variety with many
peculiarities, such as having only one of the three semicircular canals
of the ear well developed. It has a strong tendency to waltz round and
round in circles without sufficient cause and to trip sideways towards
its dormitory instead of proceeding in the orthodox head-on fashion. But
this freak is a very educable creature, as Professor Yerkes has shown.
In a careful way he confronted his mouse-pupil with alternative pathways
marked by different degrees of illumination, or by different colours. If
the mouse chose compartment A, it found a clear passage direct to its
nest; if it chose compartment B, it was punished by a mild electric
shock and it had to take a roundabout road home. Needless to say, the A
compartment was sometimes to the right hand, sometimes to the left, else
mere position would have been a guide. The experiments showed that the
dancing mice learn to discriminate the right path from the wrong, and
similar results have been got from other mammals, such as rats and
squirrels. There is no proof of learning by ideas, but there is proof of
learning by experience. And the same must be true in wild life.

Many mammals, such as cats and rats, learn how to manipulate
puzzle-boxes and how to get at the treasure at the heart of a Hampton
Court maze. Some of the puzzle-boxes, with a reward of food inside, are
quite difficult, for the various bolts and bars have to be dealt with in
a particular order, and yet many mammals master the problem. What is
plain is that they gradually eliminate useless movements, that they make
fewer and fewer mistakes, that they eventually succeed, and that they
register the solution within themselves so that it remains with them for
a time. It looks a little like the behaviour of a man who learns a game
of skill without thinking. It is a learning by experience, not by ideas
or reflection. Thus it is very difficult to suppose that a rat or a cat
could form any idea or even picture of the Hampton Court maze--which
they nevertheless master.

Learning Tricks

Given sufficient inducement many of the cleverer mammals will learn to
do very sensible things, and no one is wise enough to say that they
never understand what they are doing. Yet it is certain that trained
animals often exhibit pieces of behaviour which are not nearly so clever
as they look. The elephant at the Belle Vue Gardens in Manchester used
to collect pennies from benevolent visitors. When it got a penny in its
trunk it put it in the slot of an automatic machine which delivered up a
biscuit. When a visitor gave the elephant a halfpenny it used to throw
it back with disgust. At first sight this seemed almost wise, and there
was no doubt some intelligent appreciation of the situation. But it was
largely a matter of habituation, the outcome of careful and prolonged
training. The elephant was laboriously taught to put the penny in the
slot and to discriminate between the useful pennies and the useless
halfpennies. It was not nearly so clever as it looked.

Using their Wits

In the beautiful Zoological Park in Edinburgh the Polar Bear was wont to
sit on a rocky peninsula of a water-filled quarry. The visitors threw in
buns, some of which floated on the surface. It was often easy for the
Polar Bear to collect half a dozen by plunging into the pool. But it had
discovered a more interesting way. At the edge of the peninsula it
scooped the water gently with its huge paw and made a current which
brought the buns ashore. This was a simple piece of behaviour, but it
has the smack of intelligence--of putting two and two together in a
novel way. It suggests the power of making what is called a "perceptual
inference."

On the occasion of a great flood in a meadow it was observed that a
number of mares brought their foals to the top of a knoll, and stood
round about them protecting them against the rising water. A dog has
been known to show what was at any rate a plastic appreciation of a
varying situation in swimming across a tidal river. It changed its
starting-point, they say, according to the flow or ebb of the tide.
Arctic foxes and some other wild mammals show great cleverness in
dealing with traps, and the manipulative intelligence of elephants is
worthy of all our admiration.

Sec. 7

Why is there not more Intelligence?

When we allow for dexterity and power of association, when we recognise
a certain amount of instinctive capacity and a capacity for profiting by
experience in an intelligent way, we must admit a certain degree of
disappointment when we take a survey of the behaviour of mammals,
especially of those with very fine brains, from which we should
naturally expect great things. Why is there not more frequent exhibition
of intelligence in the stricter sense?

The answer is that most mammals have become in the course of time very
well adapted to the ordinary conditions of their life, and tend to leave
well alone. They have got their repertory of efficient answers to the
ordinary questions of everyday life, and why should they experiment? In
the course of the struggle for existence what has been established is
efficiency in normal circumstances, and therefore even the higher
animals tend to be no cleverer than is necessary. So while many mammals
are extraordinarily efficient, they tend to be a little dull. Their
mental equipment is adequate for the everyday conditions of their life,
but it is not on sufficiently generous lines to admit of, let us say, an
interest in Nature or adventurous experiment. Mammals always tend to
"play for safety."

We hasten, however, to insert here some very interesting saving clauses.

Experimentation in Play

A glimpse of what mammals are capable of, were it necessary, may be
obtained by watching those that are playful, such as lambs and kids,
foals and calves, young foxes and others. For these young creatures let
themselves go irresponsibly, they are still unstereotyped, they test
what they and their fellows can do. The experimental character of much
of animal play is very marked.

It is now recognised by biologists that play among animals is the young
form of work, and that the playing period, often so conspicuous, is
vitally important as an apprenticeship to the serious business of life
and as an opportunity for learning the alphabet of Nature. But the
playing period is much more; it is one of the few opportunities animals
have of making experiments without too serious responsibilities. Play is
Nature's device for allowing elbow-room for new departures
(behaviour-variations) which may form part of the raw materials of
progress. Play, we repeat, gives us a glimpse of the possibilities of
the mammal mind.

Other Glimpses of Intelligence

A squirrel is just as clever as it needs to be and no more; and of some
vanishing mammals, like the beaver, not even this can be said. Humdrum
non-plastic efficiency is apt to mean stagnation. Now we have just seen
that in the play of young mammals there is an indication of unexhausted
possibilities, and we get the same impression when we think of three
other facts. (_a_) In those mammals, like dog and horse, which have
entered into active cooperative relations with man, we see that the mind
of the mammal is capable of much more than the average would lead us to
think. When man's sheltering is too complete and the domesticated
creature is passive in his grip, the intelligence deteriorates. (_b_)
When we study mammals, like the otter, which live a versatile life in a
very complex and difficult environment, we get an inspiriting picture of
the play of wits. (_c_) Thirdly, when we pass to monkeys, where the
fore-limb has become a free hand, where the brain shows a relatively
great improvement, where "words" are much used, we cannot fail to
recognise the emergence of something new--a restless inquisitiveness, a
desire to investigate the world, an unsatisfied tendency to experiment.
We are approaching the Dawn of Reason.

THE MIND OF MONKEYS

Sec. 8

There is a long gamut between the bushy-tailed, almost squirrel-like
marmosets and the big-brained chimpanzee. There is great variety of
attainment at different levels in the Simian tribe.

Keen Senses

To begin at the beginning, it is certain that monkeys have a first-class
sensory equipment, especially as regards sight, hearing, and touch. The
axes of the two eyes are directed forwards as in man, and a large
section of the field of vision is common to both eyes. In other words,
monkeys have a more complete stereoscopic vision than the rest of the
mammals enjoy. They look more and smell less. They can distinguish
different colours, apart from different degrees of brightness in the
coloured objects. They are quick to discriminate differences in the
shapes of things, e.g. boxes similar in size but different in shape, for
if the prize is always put in a box of the same shape they soon learn
(by association) to select the profitable one. They learn to
discriminate cards with short words or with signs printed on them,
coming down when the "Yes" card is shown, remaining on their perch when
the card says "No." Bred to a forest life where alertness is a
life-or-death quality, they are quick to respond to a sudden movement or
to pick out some new feature in their surroundings. And what is true of
vision holds also for hearing.

Power of Manipulation

Another quality which separates monkeys very markedly from ordinary
mammals is their manipulative expertness, the co-ordination of hand
and eye. This great gift follows from the fact that among monkeys the
fore-leg has been emancipated. It has ceased to be indispensable as an
organ of support; it has become a climbing, grasping, lifting, handling
organ. The fore-limb has become a free hand, and everyone who knows
monkeys at all is aware of the zest with which they use their tool. They
enjoy pulling things to pieces--a kind of dissection--or screwing the
handle off a brush and screwing it on again.

[Illustration: _Photo: W. P. Dando_

BABY ORANG

Notice the small ears and the suggestion of good temper. The mother
orang will throw prickly fruits and pieces of branches at those who
intrude on her maternal care.]

[Illustration: _Photo: Gambier Bolton._

ORANG-UTAN

A large and heavy ape, frequenting forests in Sumatra and Borneo, living
mainly in trees, where a temporary nest is made. The expression is
melancholy, the belly very protuberant, the colour yellow-brown, the
movements are cautious and slow.]

[Illustration: 1. CHIMPANZEE

2. BABY ORANG-UTAN

3. ORANG-UTAN

4. BABY CHIMPANZEES

_Photos: James's Press Agency._

In his famous book on _The Expression of the Emotions in Man and
Animals_ (1872) Charles Darwin showed that many forms of facial
expression familiar in man have their counterparts in apes and other
mammals. He also showed how important the movements of expression are as
means of communication between mother and offspring, mate and mate, kith
and kin.

The anthropoid apes show notable differences of temperament as the
photographs show. The chimpanzee is lively, cheerful, and educable. The
orang is also mild of temper, but often and naturally appears melancholy
in captivity. This is not suggested, however, by our photograph of the
adult. Both chimpanzee and orang are markedly contrasted with the fierce
and gloomy gorilla.]

Activity for Activity's Sake

Professor Thorndike hits the nail on the head when he lays stress on the
intensity of activity in monkeys--activity both of body and mind. They
are pent-up reservoirs of energy, which almost any influence will tap.
Watch a cat or a dog, Professor Thorndike says; it does comparatively
few things and is content for long periods to do nothing. It will be
splendidly active in response to some stimulus such as food or a friend
or a fight, but if nothing appeals to its special make-up, which is very
utilitarian in its interests, it will do nothing. "Watch a monkey and
you cannot enumerate the things he does, cannot discover the stimuli to
which he reacts, cannot conceive the _raison d'etre_ of his pursuits.
Everything appeals to him. He likes to be active for the sake of
activity."

This applies to mental activity as well, and the quality is one of
extraordinary interest, for it shows the experimenting mood at a higher
turn of the spiral than in any other creature, save man. It points
forward to the scientific spirit. We cannot, indeed, believe in the
sudden beginning of any quality, and we recall the experimenting of
playing mammals, such as kids and kittens, or of inquisitive adults like
Kipling's mongoose, Riki-Tiki-Tavi, which made it his business in life
to find out about things. But in monkeys the habit of restless
experimenting rises to a higher pitch. They appear to be curious about
the world. The psychologist whom we have quoted tells of a monkey which
happened to hit a projecting wire so as to make it vibrate. He went on
repeating the performance hundreds of times during the next few days. Of
course, he got nothing out of it, save fun, but it was grist to his
mental mill. "The fact of mental life is to monkeys it own reward." The
monkey's brain is "tender all over, functioning throughout, set off in
action by anything and everything."

Sheer Quickness

Correlated with the quality of restless inquisitiveness and delight in
activity for its own sake there is the quality of quickness. We mean not
merely the locomotor agility that marks most monkeys, but quickness of
perception and plan. It is the sort of quality that life among the
branches will engender, where it is so often a case of neck or nothing.
It is the quality which we describe as being on the spot, though the
phrase has slipped from its original moorings. Speaking of his Bonnet
Monkey, an Indian macaque, second cousin to the kind that lives on the
Rock of Gibraltar, Professor S. J. Holmes writes: "For keenness of
perception, rapidity of action, facility in forming good practical
judgments about ways and means of escaping pursuit and of attaining
various other ends, Lizzie had few rivals in the animal world.... Her
perceptions and decisions were so much more rapid than my own that she
would frequently transfer her attention, decide upon a line of action,
and carry it into effect before I was aware of what she was about. Until
I came to guard against her nimble and unexpected manoeuvres, she
succeeded in getting possession of many apples and peanuts which I had
not intended to give her except upon the successful performance of some
task."

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