METHODS OF DEFENCE.
FLIGHT--FEINT--RESISTANCE IN COMMON BY SOCIAL
ANIMALS--SENTINELS.
Studying the animal kingdom in the manner here adopted, that is to say
by passing in review the various manifestations of zoological life, we
are necessarily led to find certain industries which are opposed to
others. We have seen the various methods of hunting; but attack calls
forth defence. In the struggle for life we find the action of beings
on other beings, and the re-action of these latter; the final result
is the expression of the difference between the two according as one
or the other is stronger.
_Flight._--Just as the most rudimentary method of attack is simple
pursuit, so the most simple and natural method of defence is flight;
but if very fleet animals like hares, gazelles, and deer can escape by
simply exerting their maximum rapidity, it is not always thus, and
certain species exercise in flight perfected methods appropriate to
circumstances, and so raise this method of defence to an art.
Of all animals the Ape most skilfully directs his flight. There is no
question that in his intelligence we may find every rudiment of our
own; but of all his qualities none more nearly approximates him to us
than his courage. There are no animals, not even the great beasts of
prey, who are so brave as Man and the Ape, and who are capable of so
much presence of mind. It is perhaps this bravery which, joined to his
sociability, has most contributed to assure the supremacy of the one.
As to the other, the road has been barred to him by his better-endowed
cousin; he is disappearing before Man, and not before nature or other
animals. In thinly-inhabited regions he is still the king. It is
generally considered that the Lion is the incarnation of courage, but
he is the strongest and the best armed; there is none before whom he
need tremble. In captivity he allows himself to be struck by the
tamer, which the most miserable ape would never suffer. The Lion will
struggle with extreme energy without calculating the difference of
strength between his opponent and himself, and will resist as long as
he is able to move. The Ape directs all his courage and presence of
mind to order his flight when he has recognised a danger that is
insurmountable. He does not act like those infatuated beasts who lose
their head and rush away trembling, in their precipitation paralysing
a great part of their resources. A band of apes in flight utilises all
obstacles that can be interposed between themselves and the pursuer;
they retire without excessive haste and take advantage of the first
shelter met with; a female never abandons her young, and if a young
one remains behind, and is in danger of being taken, the old males of
the troop go back boldly to save it at the peril of their lives. In
this connection many heroic facts have been narrated. This animal has
too frequently been judged by comparison with ourselves; he has been
regarded as a human caricature and covered with ridicule. We obtain a
very much higher idea of him if we compare him with other animals.
Always and everywhere there has been a prejudiced insistence on his
defects; we perceive them so easily because they are an exaggeration
of our own; but he also possesses qualities of the first order.
As an example of flight arranged with intelligence, we have already
seen how the _Formica fusca_ profits by the difficulty experienced by
the _Polyergus_ in climbing. It hastily gains the summit of a blade of
grass, to place there in safety the larvae which the others wish to
carry away. The ruses adopted in flight are as varied as those of
attack. Every animal tries to profit as much as possible by all his
resources.
Larks, a feeble race of birds, rise higher in the air than any
rapacious bird, and this is often a cause of safety. Their greatest
enemy is the Hobby (_Hypotriorchis sublutes_). They fear him greatly,
so that as soon as one appears singing ceases, and each suddenly
closes his wings, falls to the earth and hides against the soil. But
some have mounted so high to pour out their clear song that they
cannot hope to reach the earth before being seized. Then, knowing that
the bird of prey is to be feared when he occupies a more elevated
position from which he can throw himself on them, they endeavour to
remain always above him. They mount higher and higher. The enemy seeks
to pass them, but they mount still, until at last the Hobby, heavier,
and little accustomed to this rarefied air, grows tired and gives up
the pursuit.[37]
[37] _Naturgeschichte der Voegel Deutschlands_, etc.
The Gold-winged Woodpecker of the United States (_Colaptes auratus_)
often escapes Falcons either by throwing himself into the first hole
that he finds, or if he cannot find one, through seizing the trunk of
a tree with his claws. As he is a very good climber, he describes
rapid spirals around it, and the falcon cannot in flying trace such
small circles. By this method the _Colaptes_ usually escapes.[38]
[38] Audubon, _Ornithological Biography_, New York and
Edinburgh, 1831-49.
The Fox, who is so ingenious in hunting, is not less so when his own
safety is concerned. He knows when it is best to flee or to remain; he
is suspicious in a surprising degree, not only of man but also of the
engines which man prepares against him. He recognises them or smells
them. Certain facts almost lead us to suspect that he understands
their mechanism. When one of them has been surprised in his hole, and
the trap has been placed before every opening, he will not emerge from
the burrow. If hunger becomes too imperious, he recognises that
patience will only change the manner of his death, and then he decides
to dare fate; but previously he had done everything to flee without
passing over the snare. As long as he had claws and strength he
hollowed out the earth to form a new issue, but hunger rapidly
exhausted his vigour and he was not able to complete the work. Foxes
thus trapped have recognised immediately when one of these engines
went off, either owing to another animal being caught or from some
other reason. In this case the captive understands very well that the
mechanism has produced its effect, that it is no longer to be dreaded,
and he boldly emerges.
It has happened that foxes have been caught in a trap by a paw or else
by the tail, when delicately endeavouring to extract the bait.
Recognising the manner in which they are retained prisoners, certain
of them have had the intelligence and the courage to cut off with
their teeth the part engaged in the trap, and to escape thus
mutilated. St. John knew a fox who thus escaped by amputating a paw,
and who was able to earn his living for three or four years
subsequently, when he was finally caught.
In Australia great kangaroo hunts are organised. Generally the capture
is sufficiently easy, and the dogs are able to seize the kangaroo, but
sometimes he makes a long and rather original defence. If possible, he
directs his flight towards a river. If he reaches it he enters, and,
thanks to his great height, he is able to go on foot to a depth where
the dogs are obliged to swim. Arrived there, he plants himself on his
two posterior legs and his tail, and, up to his shoulders in the
water, awaits the arrival of the pack. With his anterior paws he
seizes by the head the first dog who approaches him, and, as he is
more solidly balanced than his assailant, he holds the dog's nose
beneath the water as long as he can. Unless a second dog speedily
comes to the rescue the first is inevitably drowned. If a companion
arrives to free him, he is so disturbed by this unexpected bath that
he regains the bank as quickly as possible, and has no further desire
to attack this suffocating prey. A strong and courageous old male can
thus hold his own against twenty or thirty dogs, drowning some and
frightening others, and the hunter is obliged to intervene and put an
end to this energetic defence by a bullet.[39]
[39] J. Gould, _The Mammals of Australia_, London, 1845-60.
_Feint._--Many animals, when they cannot escape danger by flight, seek
safety by various feints. The device of feigning death is especially
widespread.
Many coleopterous insects and Spiders simulate death to perfection,
although it has been ascertained that they do not always adopt the
attitude which members of their species fall into when really dead.
But they remain perfectly motionless; neither leg nor antenna stirs.
McCook, who has devoted such loving study to Spiders, remarks in his
magnificent work, that the Orbweavers, especially, possess this habit.
"One who touches an Orbweaver when hanging upon its web will often be
surprised to see it suddenly cast itself from the snare, or appear to
drop from it, as though shot off by some unseen force. Unless he
understands the nature of the creature he will be utterly at a loss to
know what has become of it. In truth it has simply dropped upon the
ground by a long thread which had been instantaneously emitted, and
had maintained the Aranead in its remarkable exit, so that its fall
was not only harmless, but its return to the web assured. The legs are
drawn up around the body, and to the inexperienced eye it has the
external semblance of death. In this condition it may be handled, it
may be turned over, it may be picked up, and, for a little while at
least, will retain its death-like appearance." Preyer, who has studied
this phenomenon in various animals, comes to the conclusion that it is
usually due to unconsciousness as the result of fright.[40] McCook is
unable to accept this theory of kataplexy, so far as Spiders are
concerned. "I have frequently watched Spiders in this condition," he
observes, "to determine the point in question, and their behaviour
always impressed me as being a genuine feigning of death, and
therefore entirely within their volition. The evidence is of such
indefinite nature that one can hardly venture to give it visible
expression, but my conviction is none the less decided. I may say,
however, that my observations indicate that the Spiders remained in
this condition as long as there seemed to be any threatened danger;
now and again the legs would be relaxed slightly, as though the
creature were about getting ready to resume its normal condition, but
at the slightest alarm withheld its purpose and relapsed into
rigidity. The slight unclasping of the legs, the faint quivering
indications of a purpose to come to life, and then the instant
suppression of the purpose, were so many evidences that the power of
volition was retained, and that the Aranead might have at once
recovered if it had been disposed to do so. Again, I think that I have
never noticed anything like that gradual emergence from the
kataplectic condition which one would naturally expect if the act were
not a voluntary one. On the contrary, the spider invariably recovered,
immediately sprang upon its legs, and hoisted itself to its snare, or
ran vigorously away among the grasses."[41]
[40] _Sammlung physiologischer Abhandlungen_, Zweite Reihe,
Erster Heft, 1878.
[41] H. C. McCook, _American Spiders_ (1889, etc.), vol. ii.
pp. 437-445. Romanes has an interesting discussion of the
habit of feigning death among animals, and cautiously
reaches the conclusion that it is very largely due, not to
kataplexy, but to intelligent action.--_Mental Evolution in
Animals_, pp. 303-316. And for some remarks on this subject
by Darwin in his Essay on Instinct, see the same volume, pp.
365, 366. Also Alix, _Esprit de nos Betes_, 1890, pp.
543-548.
Among fish, the Perch and the Sturgeon feign death; according to
Couch,[42] the Landrail, the Skylark, the Corncrake adopt the same
device. Among mammals, the best-known example is probably the Opossum.
[42] _Illustrations of Instinct_, 1847.
An Opossum (_Didelphys azarae_) of South America enters farms to
devastate the poultry yards. When he is discovered he runs away, but
is soon caught, and blows from sticks rain upon him. Seeing that he
cannot escape correction he seeks at least to save his life. Letting
his head fall and straightening his inert legs he receives the blows
without flinching. Often he is considered dead, and abandoned. The
cunning little beast, who desires nothing better, arises, shakes
himself, and rather bruised, but at all events alive, takes his way
back to the wood.
The Argentine Fox (_Canis azarae_), when caught in a trap or run down
by dogs, though it fights savagely at first, after a time drops down
and apparently dies. "When in this condition of feigning death," Mr.
W. H. Hudson remarks, "I am quite sure that the animal does not
altogether lose consciousness. It is exceedingly difficult to discover
any evidence of life in the opossum, but when one withdraws a little
way from the feigning fox, and watches him very attentively, a slight
opening of the eye may be detected; and, finally, when left to
himself, he does not recover and start up like an animal that has been
stunned, but slowly and cautiously raises his head first, and only
gets up when his foes are at a safe distance. Yet I have seen
_guachos_, who are very cruel to animals, practise the most barbarous
experiments on a captive fox without being able to rouse it into
exhibiting any sign of life. This has greatly puzzled me, since, if
death-feigning is simply a cunning habit, the animal could not suffer
itself to be mutilated without wincing. I can only believe that the
fox, though not insensible, as its behaviour on being left to itself
appears to prove, yet has its body thrown by extreme terror into that
benumbed condition which simulates death, and during which it is
unable to feel the tortures practised on it. The swoon sometimes
actually takes place before the animal has been touched, and even when
the exciting cause is at a considerable distance."[43]
[43] W. H. Hudson, _Naturalist in La Plata_, p. 203.
It is probably a measure of prudence which impels certain birds to
imitate successively the cries of neighbouring animals, in order to
persuade their enemies that all the beasts in creation are brought
together in this spot except themselves. It is perhaps going a little
too far to suppose so reflective and diplomatic a motive, but it is
not doubtful that in certain cases this custom can be very useful to
them by putting their enemies on the wrong scent. In North America
nearly all the species of the Cassique family have this custom. If
they wish to deceive the ears of the great Falcons who watch them--or
is it simple amusement?--they interrupt their own song to introduce
the most varied melodies. If a sheep bleats, the bird immediately
replies to the bleating; the clucking of a turkey, the cackling of a
goose, the cry of the toucan are noted and faithfully reproduced. Then
the Cassique returns to his own special refrain, to abandon it anew on
the first opportunity.[44]
[44] Waterton, _Wanderings in South America_ (First Journey), ch. iii.
Not only do animals thus feign death in order to secure their own
safety, but the female sometimes endeavours to attract an enemy's
attention and feigns to be wounded in order to decoy him away from her
young. This trick is adopted especially by birds. In illustration of
this it will be sufficient to quote from Bendire's _Life Histories of
North American Birds_ some observations by Mr. Ernest Thompson of
Toronto, regarding the Canadian Ruffled Grouse (_Bonasa umbellus
togata_), commonly called the Partridge by Canadians:--"Every field
man must be acquainted with the simulation of lameness, by which many
birds decoy or try to decoy intruders from their nests. This is an
invariable device of the Partridge, and I have no doubt that it is
quite successful with the natural foes of the bird; indeed it is often
so with Man. A dog, as I have often seen, is certain to be misled and
duped, and there is little doubt that a mink, skunk, racoon, fox,
coyote, or wolf would fare no better. Imagine the effects of the
bird's tactics on a prowling fox: he has scented her as she sits; he
is almost upon her, but she has been watching him, and suddenly, with
a loud 'whirr,' she springs up and tumbles a few yards before him. The
suddenness and noise with which the bird appears cause the fox to be
totally carried away; he forgets all his former experience, he never
thinks of the eggs, his mind is filled with the thought of the wounded
bird almost within his reach; a few more bounds and his meal will be
secured. So he springs and springs, and very nearly catches her, and
in his excitement he is led on, and away, till finally the bird flies
off, leaving him a quarter of a mile or more from the nest.
"If instead of eggs the Partridge has chicks, she does not await the
coming of the enemy, but runs to meet and mislead him ere yet he is in
the neighbourhood of the brood; she then leads him far away, and
returning by a circuitous route, gathers her young together again by
her clucking. When surprised she utters a well-known danger-signal, a
peculiar whine, whereupon the young ones hide under logs and among
grass. Many persons say they will each seize a leaf in their beaks and
then turn over on their backs. I have never found any support for this
idea, although I have often seen one of the little creatures crawl
under a dead leaf."[45]
[45] Bendire, _Life Histories of North American Birds_
(_Smithsonian Contributions to Knowledge_, vol. xxviii.),
1892, p. 64.
_Resistance in common by social animals._--If neither flight nor feint
has saved an animal from the hunter, he naturally fights as long as he
can, but this struggle _in extremis_ is rarely crowned with success.
Certain species, especially those which live in society, are able
nevertheless, by uniting their efforts, to resist enemies who would
easily triumph over them if they were isolated.
Among tribes of Apes mutual assistance, as described by Brehm, is
common. When by chance a bird of prey, such as an eagle, has thrown
himself on a young ape who is amusing himself far from the maternal
eye, the little one does not let himself be taken without resistance;
he clings to the branches and utters shrill and despairing cries. His
appeals are heard, and in an instant a dozen agile males arrive to
save him; they throw themselves on the imprudent ravisher and seize
him, one by the claw, another by the neck, another by a wing, pulling
him about and harassing him. The bird struggles as well as he can,
distributing around him blows from talons and beak. But he is often
strangled, and when his temerity does not receive this extreme
punishment, the feathers which fall from him when he flies away bear
witness that he has not emerged unscathed from the scuffle.
Animals like Buffaloes resist by a common defence the most terrible
Carnivora. Even the Tiger is their victim, although if one of them met
that wild beast alone he would surely become its prey. Being very
agile, the tiger can reach by one leap the back of the ruminant, whose
brutal and massive force cannot thus be exercised; but the feline who
falls into the midst of a troop fares very badly. One buffalo falls on
him with lowered horns, and with a robust blow of the head throws him
into the air. The tiger cannot regain his senses, for as soon as he
reaches the ground, and often even before, he is again seized and
thrown towards other horns. Thus thrown from one to another like a
ball, he is promptly put to death.
The less terrible Carnivora give Buffaloes no trouble. Wolves do not
dare to attack them when they are united; they await in ambush the
passage of some strayed calf, and rapidly gain possession of it before
the rest of the flock are aware, or they would dearly pay for their
attack.
The Bisons of North America, near relatives of the Buffaloes, also
repulse Wolves in common; and if Man succeeds better against them it
is owing to the skill which he shows in hiding himself and not
attracting their attention. Every one knows how Indians hunt the Bison
with arrows, and his pursuit is very risky to the hunter, for he must
not be discovered by the game, as he would then be trodden underfoot
or disembowelled. In the immense prairies where these ruminants feed,
a few Indians covered by bisons' skins advance on all fours, so that
nothing betrays their presence. The victims fall one by one beneath
silent blows, and their companions, who can see nothing suspicious in
the neighbourhood, are not disturbed, supposing them, no doubt, to be
peacefully resting.
It is not only against other animals that these great mammals have to
defend themselves; they are much afraid of heat, and they are
accustomed, especially in the south of Persia, to ruminate while lying
in the water during the hot hours of the day. They only allow the end
of the snout, or at most the head, to appear. It is a curious
spectacle when fording a river to see emerge from the reeds the great
heads and calm eyes of the Buffaloes, who follow with astonishment all
the movements of the horsemen, although nothing will disturb their
sweet and fresh siesta.
But let us return to defences arranged in common. Horses are extremely
sociable, and in the immense pampas of South America those who become
wild again live in large troops. In difficult circumstances they help
one another. If a great danger threatens them all the colts and mares
assemble together, and the stallions form a circle round the group,
ready to drive back the assailant. But they do not accomplish this
manoeuvre in the presence of an enemy of small importance. When a wolf
appears on the plain all the males run after him, seeking to strike
him with their feet and kill him, unless prompt flight delivers him
from their blows.
The sociable humour of these horses makes them compassionate towards
their fellows who are enslaved by man, and if a harnessed cart meets
on its road a free band, it is a serious matter to the owner. They run
up and surround the enslaved horse, saluting him with their cries and
gambols, having the air of inviting him to throw his harness to the
winds and follow them on the plain, where grass grows for all without
work. Naturally the driver endeavours to preserve his noble conquest,
and distributes blows with the whip to those who wish to debauch it.
Then the wild horses become furious, and throw themselves on the
vehicle; they break it with their feet and cut their comrade's traces
with their teeth to enable him to share their own free life. The
enterprise satisfactorily concluded, they gallop away neighing in
triumph.
It is owing to their union in large bands that Crows have so little to
fear from diurnal birds of prey; if one approaches, they do not
hesitate to throw themselves on him altogether. The Great Horn Owl,
however, causes many ravages among them; for when asleep at night the
Crow is without defence against the ravisher, for whom, on the
contrary, obscurity is propitious. Thus they recognise him as a
hereditary enemy, and never allow an opportunity of revenge to pass
without profiting by it. If by chance an owl appears by day and one of
them perceives him, immediately a clamour arises--a veritable cry of
war; all those who are in the neighbourhood fly to the spot, and
business ceases; the nocturnal bird of prey is assaulted, riddled with
blows from beaks, stunned, his feathers torn out, and, notwithstanding
his defence, he succumbs to numbers.
In all the preceding examples the social species unite for the common
security the forces and effects which they can derive from their own
organs.
I have spoken of the Apes and described how they defend themselves
with their hands and teeth; but in certain cases they use weapons,
employing foreign objects like a club or like projectiles.
Acts of this nature are considered to indicate a high degree of
development, and it has often been repeated that they are the appanage
of man alone; we have, however, seen the _Toxotes_, who, like all
fishes, is not particularly intelligent, squirt water on to his
victims. It is not easy to understand how a greater intellectual
effort is required to throw a stone with the hand than to project
water with the mouth. This is what the apes do, throwing on their
assailants from the heights of trees everything which comes to hand:
cocoa-nuts, hard fruits, fragments of wood, etc.
Baboons (_Cynocephali_) who usually live in the midst of rocks protect
their retreat by rolling very heavy blocks on to their aggressors, or
by forcibly throwing stones about the size of the fist. As these bands
may contain from a hundred to one hundred and fifty individuals, it is
a veritable hail of stones of all sizes which they roll down from the
heights of the mountains where they find shelter.
_Sentinels._--Not only do Apes know how to face danger or to avoid it
by a prudent flight, but they also seek to foresee it, and to avoid
exposing themselves to it. A troop of Apes, according to Brehm,
generally places the leadership in the hands of a robust and
experienced male. This primitive royalty is founded partly on the
confidence inspired by an old chief, and partly by the fear inspired
by his muscular arms and ferocious canine teeth. (Fig. 9.) He gives
himself a great deal of trouble for the security of his subjects, and
does not abuse the authority which he possesses. Always at the head,
he leaps from branch to branch, and the band follows him. From time to
time he scales a tall tree, and from its heights scrutinises the
neighbourhood. If he discovers nothing suspicious a particular
guttural grunt gives information to his companions. If, on the
contrary, he perceives some danger he warns them by another cry, and
all draw in ready to follow him in his retreat, which he directs in
the same way as he guided the forward march.
Apes are not alone in relying on the experience of one of their
members. Many other animals act in the same way: antelopes, gazelles,
elephants, who advance in troops always conducted by an old male or
female who knows all the forest paths, all the places favourable to
pasture, and all the regions which must be avoided.
[Illustration: FIG. 9.]
Others, more democratic, instead of giving up the care of their safety
to one individual, which cannot be done without abdicating some degree
of individual independence, dispose around the place which they occupy
a certain number of sentinels charged to watch over the common safety.
This custom exists among prairie dogs, moufflons, crows, paroquets,
and a great many other animals. The sentinels of the crows are not
only always on the watch, but they are extremely discriminating; they
do not give a warning at the wrong time. It is certain that these
birds can distinguish a man armed with a gun from another who merely
carries a stick, and they allow the second to approach much nearer than
the first before giving the alarm.
Paroquets of all species live in joyous and noisy bands. After having
passed the night on the same tree they disperse in the neighbourhood,
not without having first posted watchers here and there, and they are
very attentive to their cries and indications.
The great Aras or Macaws, the large and handsome parrots of the Andes,
act with much prudence when circumstances make it advisable, and they
know when they ought to be on their guard. When they are in the depths
of the forest, their own domain, they gather fruits in the midst of a
deafening noise; each one squalls and cries according to his own
humour. But if they have resolved to pillage a field of maize, as
experience has taught them that these joyous manifestations would then
be unseasonable and would not fail to attract the furious proprietor,
they consummate the robbery in perfect silence. Sentinels are placed
on the neighbouring trees. To the first warning a low cry responds; on
the second, announcing a nearer danger, all the band fly away with
vociferations which need no longer be restrained. The common Crane
(_Grus cinerea_), still more far-seeing to avoid a possible future
danger, despatches scouts who are thus distinct from sentinels who
inform their fellows of present danger.[46]
[46] E. Poppig, _Fragmenta zoologica itineris Chilensis_,
1829-30.
When these birds have been disturbed in any spot, they never return
without great precautions. Before arriving, they stop; a few only go
circumspectly forward, examining everything, and coming back to make
their report. If this is not satisfactory the troop remains
suspicious, sending new messengers. When they are at last assured that
there is really nothing to fear, the rest follow.
Thus by the most varied methods animals endeavour to save their
threatened lives, and succeed to some extent in attaining safety.
Destruction and the chase on one side, conservation and flight on the
other: these are the two chief acts which occupy living beings. Many,
however, less threatened, succeed in perfecting their manner of life,
and employ their industry in less pressing occupations than eating
others or preventing others from eating them.