Dance of Ypecaha
Bails.
voice, exerted to
its utmost pitch and expressive of extreme terror, frenzy, and
despair. A long, piercing shriek, astonishing for its vehemence
and power, is succeeded by a lower note, as if in the first the
creature had well nigh exhausted itself: this double scream is
repeated several times, and followed by other sounds, resembling,
as they rise and fall, half smothered cries of pains and moans of
anguish. Suddenly the unearthly shrieks are
268
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Plata.
renewed in all
their power. While screaming the birds rush from side to side, as
if possessed with madness, the wings spread and vibrating, the
long-beak wide open and raised vertically. This exhibition lasts
three or four minntes, after which the assembly peacefully breaks
up.
The singular
wattled, wing-spurred, and long-, toed jacana has a remarkable
performance, which seems specially designed to bring out the
concealed
Wing-display of
Jacanas.
beauty of the
silky, greenish-golden wing-quills-The birds go singly or in
pairs, and a dozen or fifteen individuals may be found in a
marshy place feeding within sight of each other. Occasionally, in
response to a note of invitation, they all in a moment leave off
feeding and. fly to one spot, and, forming a close cluster, and
emitting short, excited, rapidly repeated notes, display their
wings, like beautiful flags grouped loosely together: some
hold
Music and Dancing in
Nature. 269
the wings up
vertically and motionless; others, half open and vibrating
rapidly, while still others wave them up and down with a slow,
measured motion.
In the ypecaha and
jacana displays both sexes take part. A stranger performance is
that of the spur-winged lapwing of the same region--a species
resembling the lapwing of Europe, but a third larger, brighter
coloured, and armed with spurs. The lapwing display, called by
the natives its "dance," or "serious dance"--by which they mean
square dance--requires three birds for its performance, and is,
so far as I know, unique in this respect. The birds are so fond
of it that they indulge in it all the year round, and at frequent
intervals during the day, also on moonlight nights. If a person
watches any two birds for some time--for they live in pairs--he
will see another lapwing, one of a neighbouring couple, rise up
and fly to them, leaving his own mate to guard their chosen
ground; and instead of resenting this visit as an unwarranted
intrusion on their domain, as they would certainly resent the
approach of almost any other bird, they welcome it with notes and
signs of pleasure. Advancing to the visitor, they place
themselves behind it; then all three, keeping step, begin a rapid
march, uttering resonant drumming notes in time with their
movements; the notes of the pair behind being emitted in a
stream, like a drum-roll, while the leader utters loud single
notes at regular intervals. The march ceases; the leader elevates
his wings and stands erect and motionless, still uttering loud
notes; while the other two, with
270
The Naturalist in La
Plata.
puffed-out plumage
and standing exactly abreast stoop forward and downward until the
tips of their beaks touch the ground, and, sinking their
rhythmical voices to a murmur, remain for some time in this
posture. The performance is then over and the visitor goes back
to his own ground and mate, to receive a visitor himself later
on.
Dance of Spur-winged
Lapwings.
In the Passerine
order, not the least remarkable displays are witnessed in birds
that are not accounted songsters, as they do not possess the
highly developed vocal organ confined to the suborder Oscines.
The tyrant-birds, which represent in South America the
fly-catchers of the Old World, all have displays of some kind; in
a vast majority of cases these are simply joyous, excited
duets
Music and Dancing in
Nature. 271
between male and
female, composed of impetuous and more or less confused notes and
screams, accompanied with beating of wings and other gestures. In
some species choruses take the place of duets, while in others
entirely different forms of display have been developed. In one
group--Cnipolegus--the male indulges in solitary antics, while
the silent, modest-coloured female keeps in hiding. Thus, the
male of Cnipolegus Hudsoni, an intensely black-plumaged species
with a concealed white wing-band, takes his stand on a dead twig
on the summit of a bush. At intervals he leaves his perch,
displaying the intense white on the quills, and producing, as the
wings are thrown open and shut alternately, the effect of
successive flashes of light. Then suddenly the bird begins
revolving in the air about its perch, like a moth wheeling round
and close to the flame of a candle, emitting a series of sharp
clicks and making a loud humming with the wings. While performing
this aerial waltz the black and white on the quills mix, the
wings appearing like a grey mist encircling the body. The
fantastic dance over, the bird drops suddenly on to its perch
again; and, until moved to another display, remains as stiff and
motionless as a bird carved out of jet.
The performance of
the scissors-tail, another tyrant-bird, is also remarkable. This
species is grey and white, with black head and tail and a
crocus-yellow crest. On the wing it looks like a large swallow,
but with the two outer tail-feathers a foot long. The
scissors-tails always live in pairs, but at sunset several pairs
assemble, the birds calling excitedly to each other; they then
mount
272 The Naturalist
in La Plata.
upwards, like
rockets, to a great height in the anand, after wheeling about for
a few moments, pro-cipitate themselves downwards with amazing
violence in a wild zigzag, opening and shutting the long
tail-feathers like a pair of shears, and producing loud whirring
sounds, as of clocks being wound rapidly up, with a slight pause
after each turn of the key. This aerial dance over, they alight
in separate couples on the tree tops, each couple joining in a
kind of duet of rapidly repeated, castanet-like
sounds.
The displays of the
wood-hewers, or Dendrocolap-tidae, another extensive family,
resemble those of the tyrant-birds in being chiefly duets, male
and female singing excitedly in piercing or resonant voices, and
with much action. The habit varies somewhat in the cachalote, a
Patagonian species of the genus Homorus, about the size of the
missel-thrush. Old and young birds live in a family together, and
at intervals, on any fine day, they engage in a grand screaming
contest, which may be heard distinctly at a distance of a mile
and a half. One bird mounts on to a bush and calls, and instantly
all the others hurry to the spot, and burst out into a chorus of
piercing cries that sound like peals and shrieks of insane
laughter. After the chorus, they all pursue each other wildly
about among the bushes for some minutes.
In some groups the
usual duet-like performances have developed into a kind of
harmonious singing, which is very curious and pleasant to hear.
This is pre-eminently the case with the oven-birds, as D'Orbigney
first remarked. Thus, in the red oven-
Music and Dancing in
Nature. 273
bird, the first
bird, on the appearance of its mate flying to join it, begins to
emit loud, measured notes, and sometimes a continuous trill,
somewhat metallic in sound; but immediately on the other bird
striking in this introductory passage is changed to triplets,
strongly accented on the first note, in a tempo vivace;
while the second bird utters loud single notes in the same time.
While thus singing they stand facing each other, necks
outstretched and tails expanded, the wings of the first bird
vibrating rapidly to the rapid utterance, while those of the
second bird beat measured time. The finale consists of three or
four notes, uttered by the second bird alone, strong and clear,
in an ascending scale, the last very piercing.
In the melodists
proper the displays, in a majority of cases, are exclusively
vocal, the singer sitting still on his perch. In the Troupials, a
family of starling-like birds numbering about one hundred and
forty species, there are many that accompany singing with pretty
or grotesque antics. The male screaming cow-bird of La Plata,
when perched, emits a hollow-sounding internal note that swells
at the end into a sharp metallic ring, almost bell-like: this is
uttered with wings and tail spread and depressed, the whole
plumage being puffed out as in a strutting turkey-cock, while the
bird hops briskly up and down on its perch as if dancing. The
bell-like note of the male is followed by an impetuous scream
from the female, and the dance ends. Another species, the common
Argentine cow-bird of La Plata, when courting puffs out his
glossy rich violet plumage, and, with wings vibrating, emits a
succes-
T
274 The Naturalist
in La Plata.
sion of deep
internal notes, followed by a set song in clear, ringing tones;
and then, suddenly taking wing, he flies straight away, close to
the surface, fluttering like a moth, and at a distance of twenty
to thirty yards turns and flies in a wide circle round the
female, singing loudly all the time, hedging her in with melody
as it were.
Many songsters in
widely different families possess the habit of soaring and
falling alternately while singing, and in some cases all the
aerial postures and movements, the swift or slow descent,
vertical, often, with oscillations, or in a spiral, and sometimes
with a succession of smooth oblique lapses, seem to have an
admirable correspondence with the changing and falling
voice--melody and motion being united in a more intimate and
beautiful way than in the most perfect and poetic forms of human
dancing.
One of the soaring
singers is a small yellow field-finch of La Plata--Sycalis
luteola; and this species, like some others, changes the form of
its display with the seasons. It lives in immense flocks, and
during the cold season it has, like most finches, only aerial
pastimes, the birds wheeling about in a cloud, pursuing each
other with lively chirpings. In August, when the trees begin to
blossom, the flock betakes itself to a plantation, and, sitting
on the branches, the birds sing in a concert of innumerable
voices, producing a great volume of sound, as of a high wind when
heard at a distance. Heard near, it is a great mass of melody;
not a confused tangle of musical sounds as when a host of
Troupials sing in concert, but the notes, although numberless,
seem to flow smoothly and separately, producing an
Music and Dancing in
Nature. 275
effect on the ear
similar to that which rain does on the sight, when the sun shines
on and lightens up the myriads of falling drops all falling one
way. In this manner the birds sing for hours, without
intermission, every day. Then the passion of love infects them;
the pleasant choir breaks up, and its ten thousand members
scatter wide over the surrounding fields and pasture lands.
During courtship the male has a feeble, sketchy music, but his
singing is then accompanied with very charming love antics. His
circlings about the hen-bird; his numberless advances and
retreats, and little soarings above her when his voice swells
with importunate passion; his fluttering lapses back to earth,
where he lies prone with outspread, tremulous wings, a suppliant
at her feet, his languishing voice meanwhile dying down to
lispings--all these apt and graceful motions seem to express the
very sickness of the heart. But the melody during this emotional
period is nothing. After the business of pairing and
nest-building is over, his musical displays take a new and finer
form. He sits perched on a stalk above the grass, and at
intervals soars up forty or fifty yards high; rising, he utters a
series of long melodious notes; then he descends in a graceful
spiral, the set of the motionless wings giving him the appearance
of a slowly-falling parachute; the voice then also falls, the
notes coming lower, sweeter, and more expressive until he reaches
the surface. After alighting the song continues, the strains
becoming longer, thinner, and clearer, until they dwindle to the
finest threads of sound and faintest tinklings, as from a cithern
touched by fairy fingers. The great charm of the
276 The Naturalist
in La Plata.
song is in this
slow gradation from the somewhat throaty notes emitted by the
bird when ascendino-to the excessively attenuated sounds at the
close.
In conclusion of
this part I shall speak of one species more--the white-banded
mocking-bird of Patagonia, which greatly excels all other
songsters known to me in the copiousness, variety and brilliant
character of its music. Concealed in the foliage this bird will
sing by the half-hour, reproducing with miraculous fidelity the
more or less melodious set songs of a score of species--a strange
and beautiful performance; but wonderful as it seems while it
lasts, one almost ceases to admire this mimicking bird-art when
the mocker, as if to show by contrast his unapproachable
superiority, bursts into his own divine song, uttered with a
power, abandon and joyousness resembling, but greatly exceeding,
that of the skylark "singing at heaven's gate;" the notes issuing
in a continuous torrent; the voice so brilliant and infinitely
varied, that if "rivalry and emulation" have as large a place in
feathered breasts as some imagine all that hear this surpassing
melody might well languish ever after in silent
despair.
In a vast majority
of the finest musical performances the same notes are uttered in
the same order, and after an interval the song is repeated
without any variation: and it seems impossible that we could in
any other way have such beautiful contrasts and harmonious lights
and shades--the whole song, so to speak, like a "melody sweetly
played in tune." This seeming impossibility is accomplished in
the mocking-bird's song: the notes never come in the
Music and Dancins in
Nature.
277
same order again
and again, but, as if inspired, in a changed order, with
variations and new sounds: and here again it has some resemblance
to the skylark's song, and might be described as the lark's song
with endless variations and brightened and spiritualized in a
degree that cannot be imagined.
White-banded
mocking-bird.
This mocking-bird is
one of those species that accompany music with appropriate
motions. And just as its song is, so to speak, inspired and an
im-provization, unlike any song the bird has ever uttered, so its
motions all have the same character of spontaneity, and follow no
order, and yet have a grace and passion and a perfect harmony
with the
278 The Naturalist
in La Plata.
music unparalleled
among birds possessing a similar habit. While singing he passes
from bush to bush, sometimes delaying a few moments on and at
others just touching the summits, and at times sinking out of
sight in the foliage: then, in an access of rapture, soaring
vertically to a height of a hundred feet, with measured
wing-beats, like those of a heron: or, mounting suddenly in a
wild, hurried zigzag, then slowly circling downwards, to sit at
last with tail outspread fanwise, and vans, glistening white in
the sunshine, expanded and vibrating, or waved languidly up and
down, with, a motion like that of some broad-winged butterfly at
rest on a flower.
I wish now to put
this question: What relation that we can see or imagine to the
passion of love and the business of courtship, have these dancing
and vocal performances in nine cases out of ten? In such cases,
for instance, as that of the scissors-tail tyrant-bird, and its
pyrotechnic evening displays, when a number of couples leave
their nests containing eggs and young to join in a wild aerial
dance: the mad exhibitions of ypecahas and ibises, and the
jacanas' beautiful exhibition of grouped wings: the triplet
dances of the spur-winged lapwing, to perform which two birds
already mated are compelled to call in a third bird to complete
the set: the harmonious duets of the oven-birds, and the duets
and choruses of nearly all the wood-hewers, and the wing-slapping
aerial displays of the whistling widgeons--will it be seriously
contended that the female of this species makes choice of
the
Music and Dancing in
Nature. 2 79
male able to
administer the most vigorous and artistic slaps?
The believer in the
theory would put all these cases lightly aside, to cite that of
the male cow-bird practising antics before the female and drawing
a wide circle of melody round her; or that of the jet-black,
automaton-like, dancing tyrant-bird; and concerning this species
he would probably say that the plain-plumaged female went about
unseen, critically watching the dancing of different males, to
discover the most excellent performer according to the
traditional standard. And this was, in substance, what Darwin
did. There are many species in which the male, singly or with
others, practises antics or sings during the love-season before
the female; and when all such cases, or rather those that are
most striking and bizarre, are brought together, and when it is
gratuitously asserted that the females do choose the males
that show off in the best manner or that sing best, a case for
sexual selection seems to be made out. How unfair the argument
is, based on these carefully selected cases gathered from all
regions of the globe, and often not properly reported, is seen
when we turn from the book to nature and closely consider the
habits and actions of all the species inhabiting any one
district. We see then that such cases as those described and made
so much of in the Descent of Man, and cases like those
mentioned in this chapter, are not essentially different in
character, but are manifestations of one instinct, which appears
to be almost universal among the animals. The explanation I have
to offer lies very much on the surface
2 So The Naturalist
in La Plata.
and is very simple
indeed, and, like that of Dr. Wallace1 with regard to colour and
ornaments covers the whole of the facts. We see that the inferior
animals, when the conditions of life are favourable, are subject
to periodical fits of gladness affecting them powerfully and
standing out in vivid contrast to their ordinary temper. And we
know what this feeling is--this periodic intense elation which
even civilized man occasionally experiences when in perfect
health, more especially when young. There are moments when he is
mad with joy, when he cannot keep still, when his impulse is to
sing and shout aloud and laugh at nothing, to run and leap and
exert himself in some extravagant way. Among the heavier
mammalians the feeling is manifested in loud noises, bellowings
and screamings, and in lumbering, uncouth motions--throwing up of
heels, pretended panics, and ponderous mock battles.
In smaller and
livelier animals, with greater celerity and certitude in their
motions, the feeling shows itself in more regular and often in
more complex ways. Thus, Felidae when young, and, in very agile,
sprightly species like the Puma, throughout life, simulate all
the actions of an animal hunting its prey--sudden, intense
excitement of discovery, concealment, gradual advance, masked by
interven-
1 It is curious to
find that Dr. Wallace's idea about colour has been independently
hit upon by Ruskin. Of stones he writes in Frondes
Agrestis:--"I have often had occasion to allude to the
apparent connection of brilliancy of colour with vigour of life
and purity of substance. This is pre-eminently the case in the
mineral kingdom. The perfection with which the particles of any
substance unite in crystallization, corresponds in that kingdom
to the vital power in organic nature."
Music and Dancing in
Nature. 281
ing objects, with
intervals of watching, when they crouch motionless, the eyes
flashing and tail waved from side to side; finally, the rush and
spring, when the playfellow is captured, rolled over on his back
and worried to imaginary death. Other species of the most diverse
kinds, in which voice is greatly developed, join in noisy
concerts and choruses; many of the cats may be mentioned, also
dogs and foxes, capybaras and other loquacious rodents; and in
the howling monkeys this kind of performance rises to the sublime
uproar of the tropical forest at eventide.
Birds are more
subject to this universal joyous instinct than mammals, and there
are times when some species are constantly overflowing with it;
and as they are so much freer than mammals, more buoyant and
graceful in action, more loquacious, and have voices so much
finer, their gladness shows itself in a greater variety of ways,
with more regular and beautiful motions, and with melody. But
every species, or group of species, has its own inherited form or
style of performance; and, however rude and irregular this may
be, as in the case of the pretended stampedes and fights of wild
cattle, that is the form in which the feeling will always be
expressed. If all men, at some exceedingly remote period in their
history, had agreed to express the common glad impulse, which
they now express in such an infinite variety of ways or do not
express at all, by dancing a minuet, and minuet-dancing had at
last come to be instinctive, and taken to spontaneously by
children at an early period, just as they take to walking "on
their hind legs,"
282 The Naturalist
in La Plata,
man's case would be
like that of the inferior animals.
I was one day
watching a flock of plovers, quietly feeding on the ground, when,
in a moment, all the birds were seized by a joyous madness, and
each one, after making a vigorous peck at his nearest neighbour,
began running wildly about, each trying in passing to peck other
birds, while seeking by means of quick doublings to escape being
pecked in turn. This species always expresses its glad impulse in
the same way; but how different in form is this simple game of
touch-who-touch-can from the triplet dances of the spur-winged
lapwings, with their drumming music, pompous gestures, and
military precision of movement! How different also from the
aerial performance of another bird of the same family--the
Brazilian stilt--in which one is pursued by the others, mounting
upwards in a wild, eccentric flight until they are all but lost
to view; and back to earth again, and then, skywards once more;
the pursued bird when overtaken giving place to another
individual, and the pursuing pack making the air ring with their
melodious barking cries! How different again are all these from
the aerial pastimes of the snipe, in which the bird, in its
violent descent, is able to produce such wonderful, far-reaching
sounds with its tail-feathers! The snipe, as a rule, is a
solitary bird, and, like the oscillating finch mentioned early in
this paper, is content to practise its pastimes without a
witness. In the gregarious kinds all perform together: for this
feeling, like fear, is eminently contagious, and the sight of one
bird mad with joy will quickly make
Music and Dancing in
Nature, 283
the whole flock mad.
There are also species that always live in pairs, like the
scissors-tails already mentioned, that periodically assemble in
numbers for the purpose of display. The crested screamer, a very
large bird, may also be mentioned: male and female sing somewhat
harmoniously together, with voices of almost unparalleled power:
but these birds also congregate in large numbers, and a thousand
couples, or even several thousands, may be assembled together:
and, at intervals, both by day and night, all sing in concert,
their combined voices producing a thunderous melody which seems
to shake the earth. As a rule, however, birds that live always in
pairs do not assemble for the purpose of display, but the joyous
instinct is expressed by duet-like performances between male and
female. Thus, in the three South American Passerine families, the
tyrant-birds, wood-hewers, and ant-thrushes, numbering together
between eight and nine hundred species, a very large majority
appear to have displays of this description.
In my own
experience, in cases where the male and female together, or
assembled with others, take equal parts in the set displays, the
sexes arc similar, or differ little; but where the female takes
no part in the displays the superiority of the male in brightness
of colour is very marked. One or two instances bearing on this
point may be given.
A scarlet-breasted
troupial of La Plata perches conspicuously on a tall plant in
afield, and at intervals soars up vertically, singing, and, at
the highest ascending point, flight and song end in a kind of
aerial somersault and vocal flourish at the same
284 The Naturalist
in La Plata.
moment. Meanwhile,
the dull-plumaged female is not seen and not heard: for not even
a skulking
crake lives in
closer seclusion under the herbage--so widely have the sexes
diverged in this species. Is the female, then, without an
instinct so common r --has she no sudden fits of irrepressible
gladness? Doubtless she has them, and manifests them down in her
place of concealment in lively chirpings and quick motions--the
simple, primitive form in which gladness is expressed in the
class of birds. In the various species of the genus Cnipolegus,
already mentioned, the difference in the sexes is just as great
as in the case of the troupial: the solitary, intensely black,
statuesque male has, we have seen, a set and highly fantastic
performance; but on more than one occasion I have seen four or
five females of one species meet together and have a little
simple performance all to themselves--in form a kind of lively
mock fight.
It might be objected
that when a bird takes its stand and repeats a set finished song
at intervals for an hour at a stretch, remaining quietly perched,
such a performance appears to be different in character from the
irregular and simple displays which are unmistakably caused by a
sudden glad impulse. But we are familiar with the truth that in
organic nature great things result from small beginnings--a
common flower, and our own bony skulls, to say nothing of the
matter contained within them, are proofs of it. Only a limited
number of species sing in a highly finished manner. Looking at
many species, we find every gradation, every shade, from the
simple joyous chirp and cry to the
Music and Dancing in
Nature. 285
most perfect melody.
Even in a single branch of the true vocalists we may see it--from
the chirping bunting, and noisy but tuneless sparrow, to linnet
and goldfinch and canary. Not only do a large majority of species
show the singing instinct, or form of display, in a primitive,
undeveloped state, but in that state it continues to show itself
in the young of many birds in which melody is most highly
developed in the adult. And where the development has been solely
in the male the female never rises above that early stage; in her
lively chirpings and little mock fights and chases, and other
simple forms which gladness takes in birds, as well as in her
plainer plumage, and absence of ornament, she represents the
species at some remote period. And as with song so with antics
and all set performances aerial or terrestrial, from those of the
whale and the elephant to those of the smallest
insect.
Another point
remains to be noticed, and that is the greater frequency and
fulness in displays of all kinds, including song, during the love
season. And here Dr. Wallace's colour and ornament theory helps
us to an explanation. At the season of courtship, when the
conditions of life are most favourable vitality is at its
maximum, and naturally it is then that the proficiency in all
kinds of dancing-antics, aerial and terrestrial, appears
greatest, and that melody attains its highest perfection. This
applies chiefly to birds, but even among birds there are
exceptions, as we have seen in the case of the field-finch,
Sycalis luteola. The love-excitement is doubtless pleasurable to
them, and it takes the form in which keenly pleasurable emotions
are
286 The Naturalist
in La Plata.
habitually
expressed, although not infrequently with variations due to the
greater intensity of the feeling. In some migrants the males
arrive before the females, and no sooner have they recovered from
the effects of their journey than they burst out into rapturous
singing; these are not love-strains, since the females have not
yet arrived, and pairing-time is perhaps a mouth distant; their
singing merely expresses their overflowing gladness. The forest
at that season is vocal, not only with the fine melody of the
true songsters, but with hoarse cawings, piercing cries, shrill
duets, noisy choruses, drummings, boomings, trills,
wood-tappings--every sound with which different species express
the glad impulse; and birds like the parrot that only exert their
powerful voices in screamings--because "they can do no
other"--then scream their loudest. When courtship begins it has
in many cases the effect of increasing the beauty of the
performance, giving added sweetness, verve, and brilliance to the
song, and freedom and grace to the gestures and motions. But, as
I have said, there are exceptions. Thus, some birds that are good
melodists at other times sing in a feeble, disjointed manner
during courtship. In Patagonia I found that several of the birds
with good voices--one a mocking bird--were, like the robin at
home, autumn and winter songsters.
The argument has
been stated very binefly: but little would be gained by the mere
multiplication of instances, since, however many, they would be
selected instances--from a single district, it is true, while
those in the Descent of Man were brought
Music and Dancing in
Nature. 287
together from an
immeasurably wider field; but the principle is the same in both
cases, and to what I have written it may be objected that, if,
instead of twenty-five, I had given a hundred cases, taking them
as they came, they might have shown a larger proportion of
instances like that of the cow-bird, in which the male has a set
performance practised only during the love-season and in the
presence of the female.
It is, no doubt,
true that all collections of facts relating to animal life
present nature to us somewhat as a "fantastic realm"--unavoidably
so, in a measure, since the writing would be too bulky, or too
dry, or too something inconvenient, if we did not take only the
most prominent facts that come before us, remove them from their
places, where alone they can be seen in their proper relations to
numerous other less prominent facts, and rearrange them patch
work-wise to make up our literature. But I am convinced that any
student of the subject who will cast aside his books--supposing
that they have not already bred a habit in his mind of seeing
only "in accordance with verbal statement"--and go directly to
nature to note the actions of animals for himself--actions which,
in many cases, appear to lose all significance when set down in
writing--the result of such independent investigation will be a
conviction that conscious sexual selection on the part of the
female is not the cause of music and dancing performances in
birds, nor of the brighter colours and ornaments that distinguish
the male. It is true that the females of some species, both in
the vertebrate and insect kingdoms, do exercise a
288 The Naturalist
in La Plata.
preference; but in
a vast majority of species the male takes the female he finds, or
that he is able to win from other competitors; and if we go to
the reptile class we find that in the ophidian order, which
excels in variety and richness of colour, there is no such thing
as preferential mating; and if we go to the insect class, we find
that in butterflies, which surpass all creatures in their
glorious beauty, the female gives herself up to the embrace of
the first male that appears, or else is captured by the strongest
male, just as she might be by a mantis or some other rapacious
insect.
CHAPTER
XX.
BIOGRAPHY OF THE
VIZCACHA.
(Lagostomus
Trichodactylus.)
THE vizcacha is
perhaps the most characteristic of the South American
Rodentia,1 while its habits, in some respects, are
more interesting than those of any other rodent known: it is,
moreover, the most common mammal we have on the pampas; and all
these considerations have induced me to write a very full account
of its customs. It is necessary to add that since the following
pages were written at my home on the pampas a great war of
extermination has been waged against this animal by
the
1
"According to Mr. Waterhouse, of all rodents the vizcacha is most
nearly related to marsupials; but in the points in which it
approaches this order its relations are general, that is, not to
any one marsupial species more than to another. As these points
of affinity are believed to be real and not merely adaptive, they
must be due in accordance with our view to inheritance from a
common progenitor. Therefore wo must suppose either that all
rodents, including the vizcacha, branched off from some ancient
marsupial, which will naturally have been more or less
intermediate in character with respect to all existing
marsupials; or, that both lodents and marsupials branched off
from a common progenitor. ... On either view we must suppose that
the vizcacha has retained, by inheritance, more of the characters
of its ancient progenitor than have other rodents."--DARWIN;
Origin of Species.
290
The Naturalist in La
Plata.
landowners, which
has been more fortunate in its results--or unfortunate if one's
sympathies are with the vizcacha--than the war of the Australians
against their imported rodent--the smaller and more prolific
rabbit.
The vizcachas on
the pampas of Buenos Ayres live in societies, usually numbering
twenty or thirty
Vizcachas.
members. The
village, which is called Vizcachera, is composed of a dozen or
fifteen burrows or mouths; for one entrance often serves for two
or more distinct holes. Often, where the ground is soft, there
are twenty or thirty or more burrows in an old vizcachera; but on
stony, or "tosca" soil even an old one may have no more than four
or five burrows. They are deep wide-mouthed holes, placed very
close together, the entire village covering an area
Biography of the
Vizcacha. 291
of from one hundred
to two hundred square feet of ground.
The burrows vary
greatly in extent; and usually in a vizcachera there are several
that, at a distance of from four to six feet from the entrance,
open into large circular chambers. From these chambers other
burrows diverge in all directions, some running horizontally,
others obliquely downwards to a maximum depth of six feet from
the surface: some of these burrows or galleries communicate with
those of other burrows. A vast amount of loose earth is thus
brought up, and forms a very irregular mound, fifteen to thirty
inches above the surrounding level.
It will afford some
conception of the numbers of these vizcacheras on the settled
pampas when I say that, in some directions, a person might ride
five hundred miles and never advance half a mile without seeing
one or more of them. In districts where, as far as the eye can
see, the plains are as level and smooth as a bowling-green,
especially in winter when the grass is close-cropped, and where
the rough giant-thistle has not sprung up, these mounds appear
like brown or dark spots on a green surface. They are the only
irregularities that occur to catch the eye, and consequently form
an important feature in the scenery. In some places they are so
near together that a person on horseback may count a hundred of
them from one point of view.
The sites of which
the vizcacha invariably makes choice to work on, as well as his
manner of burrow-ing, adapt him peculiarly to live and thrive on
the
292 The Naturalist
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open pampas. Other
burrowing species seem always to fix upon some spot where there
is a bank or a sudden depression in the soil, or where there is
rank herbage, or a bush or tree, about the roots of which to
begin their kennel. They are averse to commence digging on a
clear level surface, either because it is not easy for them where
they have nothing to rest their foreheads against while
scratching, or because they possess a wary instinct that impels
them to place the body in concealment whilst working on the
surface, thus securing the concealment of the burrow after it is
made. Certain it is that where large hedges have been planted on
the pampas, multitudes of opossums, weasels, skunks, armadillos,
&c., come and make their burrows beneath them; and where
there are no hedges or trees, all these species make their
kennels under bushes of the perennial thistle, or where there is
a shelter of some kind. The vizcacha, on the contrary, chooses an
open level spot, the cleanest he can find to burrow on. The first
thing that strikes the observer when viewing the vizcachera
closely is the enormous size of the entrance of the burrows, or,
at least, of several of the central ones in the mound; for there
are usually several smaller outside burrows. The pit-like opening
to some of these principal burrows is often four to six feet
across the mouth, and sometimes deep enough for a tall man to
stand up waist-deep in. How these large entrances can be made on
a level surface may be seen when the first burrow or burrows of
an incipient vizcachera are formed. It is not possible to tell
what induces a vizcacha to be the
Biography of the
Vizcacha. 293
founder of a new
community; for they increase very slowly, and furthermore are
extremely fond of each other's society; and it is invariably one
individual that leaves his native village to found a new and
independent one. If it were to have better pasture at hand, then
he would certainly remove to a considerable distance; but he
merely goes from forty to fifty or sixty yards off to begin his
work. Thus it is that in desert places, where these animals are
rare, a solitary vizcachera is never seen; but there are always
several close together, though there may be no others on the
surrounding plain for leagues. When the vizcacha has made his
habitation, it is but a single burrow, with only himself for an
inhabitant, perhaps for many months. Sooner or later, however,
others join him: and these will be the parents of innumerable
generations; for they construct no temporary lodging-place, as do
the armadillos and other species, but their posterity continues
in the quiet possession of the habitations bequeathed to it; how
long, it is impossible to say. Old men who have lived all their
lives in one district remember that many of the vizcacheras
around them existed when they were children. It is invariably a
male that begins a new village, and makes his burrow in the
following manner, though he does not always observe the same
method. He works very straight into the earth, digging a hole
twelve or fourteen inches wide, but not so deep, at an angle of
about 25 degrees with the surface. But after he has progressed
inwards a few feet, the vizcacha is no longer satisfied with
merely scattering away the loose earth he fetches
294 The Naturalist
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up, but cleans it
away so far in a straight line from the entrance, and scratches
so much on this line (apparently to make the slope gentler), that
he soon forms a trench a foot or more in depth, and often three
or four feet in length. Its use is, as I have inferred, to
facilitate the conveying of the loose earth as far as possible
from the entrance of the burrow. But after a while the animal is
unwilling that it should accumulate even at the end of this long
passage; he therefore proceeds to make two additional trenches,
that form an acute, sometimes a right angle, converging into the
first, so that when the whole is completed it takes the form of a
capital Y.
These trenches are
continually deepened and lengthened as the burrow progresses, the
angular segment of earth between them, scratched away, until by
degrees it has been entirely conveyed off, and in its place is
the one deep great unsymmetrical mouth I have already described.
There are soils that will not admit of the animals working in
this manner. Where there are large cakes of "tosca" near the
surface, as in many localities on the southern pampas, the
vizcacha makes its burrow as best he can, and without the regular
trenches. In earths that crumble much, sand or gravel, he also
works under great disadvantages.
The burrows are
made best in the black and red moulds of the pampas; but even in
such soils the entrances of many burrows are made differently. In
some the central trench is wanting, or is so short that there
appear but two passages converging directly into the burrow; or
these two trenches
Biography of the
Vizcacha. 295
may be so curved
inwards as to form the segment of a circle. Many other forms may
also be noticed, but usually they appear to be only modifications
of the most common Y-shaped system.
As I have remarked
that its manner of burrowing has peculiarly adapted the vizcacha
to the pampas, it may be asked what particular advantage a
species that makes a wide-mouthed burrow possesses over those
that excavate in the usual way. On a declivity, or at the base of
rocks or trees, there would be none; but on the perfectly level
and shelterless pampas, the durability of the burrow, a
circumstance favourable to the animal's preservation, is owing
altogether to its being made in this way, and to several barrows
being made together. The two outer trenches diverge so widely
from the mouth that half the earth brought out is cast behind
instead of before it, thus creating a mound of equal height about
the entrance, by which it is secured from water during great
rainfalls, while the cattle avoid treading over the great
pit-like entrances. But the burrows of the dolichotis, armadillo,
and other species, when made on perfectly level ground, are soon
trod on and broken in by cattle; in summer they are choked up
with dust and rubbish; and, the loose earth having all been
thrown up together in a heap on one side, there is no barrier to
the water which in every great rainfall flows in and obliterates
the kennel, drowning or driving out the tenant.
I have been minute
in describing the habitations of the vizcacha, as I esteem the
subject of prime importance in considering the zoology of
this
296 The Naturalist
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portion of America.
The vizcacha does not benefit himself alone by his perhaps unique
style of burrowing; but this habit has proved advantageous to
several other species, and has been so favourable to two of our
birds that they are among the most common species found here,
whereas without these burrows they would have been exceedingly
rare, since the natural banks in which they breed are scarcely
found anywhere on the pampas. I refer to the Minera (Geositta
cunicularia), which makes its breeding-holes in the bank-like
sides of the vizcacha's burrow, and to the little swallow
(Atticora cyanoleuca) which breeds in these excavations when
forsaken by the Minera. Few old vizcacheras are seen without some
of these little parasitical burrows in them.
Birds are not the
only beings in this way related to the vizcachas: the fox and the
weasel of the pampas live almost altogether in them. Several
insects also frequent these burrows that are seldom found
anywhere else. Of these the most interesting are:--a large
predacious nocturnal bug, shining black, with red wings; a
nocturnal Cicindela, a beautiful insect, with dark green striated
wing-cases and pale red legs; also several diminutive wingless
wasps. Of the last I have counted six species, most of them
marked with strongly contrasted colours, black, red, and white.
There are also other wasps that prey on the spiders found on the
vizcachera. All these and others are so numerous on the mounds
that dozens of them might there be collected any summer day; but
if sought for in other situations they are exceedingly rare. If
the
Biography of the
Vizcacha. 297
dry mound of soft
earth which the vizcacha elevates amidst a waste of humid,
close-growing grass is not absolutely necessary to the existence
of all these species, it supplies them with at least one
favourable condition, and without doubt thereby greatly increases
their numbers: they, too, whether predacious or preyed on, have
so many relations with other outside species, and these again
with still others, that it would be no mere fancy to say that
probably hundreds of species are either directly or indirectly
affected in their struggle for existence by the vizcacheras so
abundantly sprinkled over the pampas.
In winter the
vizcachas seldom leave their burrows till dark, but in summer
come out before sunset; and the vizcachera is then a truly
interesting spectacle. Usually one of the old males first
appears, and sits on some prominent place on the mound,
apparently in no haste to begin his evening meal. When approached
from the front he stirs not, but eyes the intruder with a bold
indifferent stare. If the person passes to one side, he deigns
not to turn his head.
Other vizcachas
soon begin to appear, each one quietly taking up his station at
his burrow's mouth, the females, known by their greatly inferior
size and lighter grey colour, sitting upright on their haunches,
as if to command a better view, and indicating by divers sounds
and gestures that fear and curiosity struggles in them for
mastery; for they are always wilder and sprightlier in their
motions than the males. With eyes fixed on the intruder, at
intervals they dodge the head, emitting at the
298 The Nattiralist
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same time an
internal note with great vehemence; and suddenly, as the danger
comes nearer, they plunge simultaneously, with a startled cry,
into their burrows. But in some curiosity is the strongest
emotion; for, in spite of their fellow's contagious example, and
already half down the entrance, again they start up to scrutinize
the stranger, and will then often permit him to walk within five
or six paces of them.
Standing on the
mound there is frequently a pair of burrowing owls (Pholeoptynx
cunicularia). These birds generally make their own burrows to
breed in, or sometimes take possession of one of the lesser
outside burrows of the village; but their favourite residence,
when not engaged in tending their eggs or young, is on the
vizcachera. Here a pair will sit all day; and I have often
remarked a couple close together on the edge of the burrow; and
when the vizcacha came out in the evening, though but a hand's
breadth from them, they did not stir, nor did he notice them, so
accustomed are these creatures to each other. Usually a couple of
the little burrowing Geositta are also present. They are lively
creatures, running with great rapidity about the mound and bare
space that surrounds it, suddenly stopping and jerking their
tails in a slow deliberate manner, and occasionally uttering
their cry, a trill, or series of quick short clear notes,
resembling somewhat the shrill excessive laughter of a child.
Among the grave, stationary vizcachas, of which they take no
heed, perhaps half a dozen or more little swallows (Atticora
cyanoleuca) are seen, now clinging altogether to the bank-like
entrance
Biography of the
Vizcacha. 299
of a burrow, now
hovering over it in a moth-like manner, as if uncertain where to
alight, and anon sweeping about in circles, but never ceasing
their low and sorrowful notes.
The vizcachera with
all its incongruous inhabitants thus collected upon it is to a
stranger one of the most novel sights the pampas
afford.
The vizcacha
appears to be a rather common species over all the extensive
Argentine territory; but they are so exceedingly abundant on the
pampas inhabited by man, and comparatively so rare in the desert
places I have been in, that I was at first much surprised at
finding them so unequally distributed. I have also mentioned that
the vizcacha is a tame familiar creature. This is in the pastoral
districts, where they are never disturbed; but in wild regions,
where he is scarce, he is exceedingly wary, coming forth long
after dark, and plunging into his burrow on the slightest alarm,
so that it is a rare thing to get a sight of him. The reason is
evident enough; in desert regions the vizcacha has several deadly
enemies in the larger rapacious mammals. Of these the puma or
lion (Felis concolor) is the most numerous, as it is also the
swiftest, most subtle, and most voracious; for, as regards these
traits, the jaguar (F. onca) is an inferior animal. To the
insatiable bloody appetite of this creature nothing comes amiss;
he takes the male ostrich by surprise, and slays that wariest of
wild things on his nest; He captures little birds with the
dexterity of a cat, and hunts for diurnal armadillos; he comes
unawares upon the deer and huanaco, and, springing like lightning
on them, dislocates their necks before their
300 The Naturalist
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bodies touch the
earth. Often after he has thus slain them, he leaves their bodies
untouched for the Polyborus and vulture to feast on, so great a
delight does he take in destroying life. The vizcacha falls an
easy victim to this subtle creature; and it is not to be wondered
at that it becomes wild to excess, and rare in regions hunted
over by such an enemy, even when all other conditions are
favourable to its increase. But as soon as these wild regions are
settled by man the pumas are exterminated, and the sole remaining
foe of the vizcacha is the fox, comparatively an insignificant
one.
The fox takes up his
residence in a vizcachera, and succeeds, after some quarrelling
(manifested in snarls, growls, and other subterranean warlike
sounds), in ejecting the rightful owners of one of the burrows,
which forthwith becomes his. Certainly the vizcachas are not much
injured by being compelled to relinquish the use of one of their
kennels for a season or permanently; for, if the locality suits
him, the fox remains with them always. Soon they grow accustomed
to the unwelcome stranger; he is quiet and unassuming in
demeanour, and often in the evening sits on the mound in their
company, until they regard him with the same indifference they do
the burrowing owl. But in spring, when the young vizcachas are
large enough to leave their cells, then the fox makes them his
prey; and if it is a bitch fox, with a family of eight or nine
young to provide for, she will grow so bold as to hunt her
helpless quarry from hole to hole, and do battle with the old
ones, and carry off the young in spite of them, so that all the
young animals in the village are even-
Biography of the
Vizcacha. 301
tually destroyed.
Often when the young foxes are large enough to follow their
mother, the whole family takes leave of the vizcachera where such
cruel havoc has been made to settle in another, there to continue
their depredations. But the fox has ever a relentless foe in man,
and meets with no end of bitter persecutions; it is consequently
much more abundant in desert or thinly settled districts than in
such as are populous, so that in these the check the vizcachas
receive from the foxes is not appreciable.
The abundance of
cattle on the pampas has made it unnecessary to use the vizcacha
as an article of food. His skin is of no value; therefore man,
the destroyer of his enemies, has hitherto been the greatest
benefactor of his species. Thus they have been permitted to
multiply and spread themselves to an amazing extent, so that the
half-domestic cattle on the pampas are not nearly so familiar
with man, or so fearless of his presence as are the vizcachas. It
is not that they do him no injury, but because they do it
indirectly, that they have so long enjoyed immunity from
persecution. It is amusing to see the sheep-farmer, the greatest
sufferer from the vizcachas, regarding them with such
indifference as to permit them to swarm on his "run," and burrow
within a stone's throw of his dwelling with impunity, and yet
going a distance from home to persecute with unreasonable
animosity a fox, skunk, or opossum on account of the small annual
loss it inflicts on the poultry-yard. That the vizcacha has
comparatively no adverse conditions to war with wherever man is
settled is evident when we consider
3O2 The Naturalist
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its very slow rate
of increase, and yet see them in such incalculable numbers. The
female has but one litter in the year of two young, sometimes of
three. She becomes pregnant late in April, and brings forth in
September; the period of gestation is, I think, rather less than
five months.
The vizcacha is
about two years growing. A full-sized male measures to the root
of the tail twenty-two inches, and weighs from fourteen to
fifteen pounds; the female is nineteen inches in length, and her
greatest weight nine pounds. Probably it is a long-lived, and
certainly it is a very hardy animal. Where it has any green
substance to eat it never drinks water; but after a long summer
drought, when for months it has subsisted on bits of dried
thistle-stalks and old withered grass, if a shower falls it will
come out of its burrows even at noonday and drink eagerly from
the pools. It has been erroneously stated that vizcachas subsist
on roots. Their food is grass and seeds; but they may also
sometimes eat roots, as the ground is occasionally seen scratched
up about the burrows. In March, when the stalks of the perennial
cardoon or Castile thistle (Cynara cardunculus) are dry, the
vizcachas fell them by gnawing about their roots, and afterwards
tear to pieces the great dry flower-heads to get the seeds
imbedded deeply in them, of which they seem very fond. Large
patches of thistle are often found served thus, the ground about
them literally white with the silvery bristles they have
scattered. This cutting down tall plants to get the seeds at the
top seems very like an act of pure intelligence; but the fact
is,
Biography of the
Vizcacha. 303
the vizcachas cut
down every tall plant they can. I have seen whole acres of maize
destroyed by them, yet the plants cut down were left untouched.
If posts be put into the ground within range of their nightly
rambles they will gnaw till they have felled them, unless of a
wood hard enough to resist their chisel-like incisors.
The strongest
instinct of this animal is to clear the ground thoroughly about
its burrows; and it is this destructive habit that makes it
necessary for cultivators of the soil to destroy all the
vizcachas in or near their fields. On the uninhabited pampas,
where the long grasses grow, I have often admired the vizcachera;
for it is there the centre of a clean space, often of half an
acre in extent, on which there is an even close-shaven turf: this
clearing is surrounded by the usual rough growth of herbs and
giant grasses. In such situations this habit of clearing the
ground is eminently advantageous to them, as it affords them a
comparatively safe spot to feed and disport themselves on, and
over which they can fly to their burrows without meeting any
obstruction, on the slightest alarm.
Of course the
instinct continues to operate where it is no longer of any
advantage. In summer, when the thistles are green, even when
growing near the burrows, and the giant thistle (Carduus mariana)
springs up most luxuriantly right on the mound, the vizcachas
will not touch them, either disliking the strong astringent sap,
or repelled by the thorns with which they are armed. As soon as
they dry, and the thorns become brittle, they are levelled;
afterwards, when the animal begins to drag
304 The Naturalist
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them about and cut
them up, as his custom is, he accidentally discovers and feasts
on the seed: for vizcachas are fond of exercising their teeth on
hard substances, such as sticks and bones, just as cats are of
"sharpening their claws" on trees.
Another remarkable
habit of the vizcacha, that of dragging to and heaping about the
mouth of his burrow every stalk he cuts down, and every portable
object that by dint of great strength he can carry, has been
mentioned by Azara, Darwin, and others. On the level plains it is
a useful habit; for as the vizcachas are continually deepening
and widening their burrows, the earth thrown out soon covers up
these materials, and so assists in raising the mound. On the
Buenos-Ayrean pampas numbers of vizcacheras would annually be
destroyed by water in the great sudden rainfalls were the mounds
loss high. But this is only an advantage when the animals inhabit
a perfectly level country subject to flooding rains; for where
the surface is unequal they invariably prefer high to low ground
to burrow on, and are thus secured from destruction by water; yet
the instinct is as strong in such situations as on the level
plains. The most that can be said of a habit apparently so
obscure in its origin and uses is, that it appears to be part of
the instinct of clearing the ground about the village. Every tall
stalk the vizcacha cuts down, every portable object he finds,
must be removed to make the surface clean and smooth; but while
encumbered with it he does not proceed further from his burrows,
but invariably re-tires towards them, and so deposits it upon the
mound. So well known is this habit, that whatever
Biography of the
Vizcacha. 305
article is lost by
night--whip, pistol, or knife--;the loser next morning visits the
vizcacheras in the vicinity, quite sure of finding it there.
People also visit the vizcacheras to pick up sticks for
firewood.
The vizcachas are
cleanly in their habits; and the fur, though it has a strong
earthy smell, is kept exceedingly neat. The hind leg and foot
afford a very beautiful instance of adaptation. Propped by the
hard curved tail, they sit up erect, and as firmly on the long
horny disks on the undersides of the hind legs as a man stands on
his feet. Most to be admired, on the middle toe the skin thickens
into a round cushion, in which the curved teeth-like bristles are
set; nicely graduated in length, so that "each particular hair"
may come into contact with the skin when the animal scratches or
combs itself. As to the uses of this appendage there can be no
difference of opinion, as there is about the serrated claw in
birds. It is quite obvious that the animal cannot scratch himself
with his hind paw (as all mammals do) without making use of this
natural comb. Then the entire foot is modified, so that this comb
shall be well protected, and yet not be hindered from performing
its office: thus the inner toe is pressed close to the middle
one, and so depressed that it comes under the cushion of skin,
and cannot possibly get before the bristles, or interfere their
coming against the skin in scratching, as certainly be the case
if this toe were free as outer one.
Again, the vizcachas
appear to form the deep trenches before the burrows by scratching
the earth
x
306 The Naturalist
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violently backwards
with the hind claws. Now these straight, sharp, dagger-shaped
claws, and especially the middle one, are so long that the
vizcacha is able to perform all this rough work without the
bristles coming into contact with the ground, and so getting worn
by the friction. The Tehuelcho Indians in Patagonia comb their
hair with a brush-comb very much like that on the vizcacha's toe,
but in their case it does not properly fulfil its office, or else
the savages make little use of it. Vizcachas have a remarkable
way of dusting themselves: the animal suddenly throws himself on
his back, and, bringing over his hind legs towards his head,
depresses them till his feet touch the ground. In this strange
posture he scratches up the earth with great1 rapidity, raising a
little cloud of dust, then rights himself with a jerk, and, after
an interval, repeats the dusting. Usually they scratch a hole in
the ground to deposit their excrements in. Whilst opening one of
the outside burrows that had no communication with the others, I
once discovered a vast deposit of their dung (so great that it
must have been accumulating for years) at the extremity. To
ascertain whether this be a constant, or only a casual habit, it
would be necessary to open up entirely a vast number of
vizcacheras. When a vizcacha dies in his burrow the carcass is,
after some days, dragged out and left upon the mound.
The language of the
vizcacha is wonderful for its variety. When the male is feeding
he frequently pauses to utter a succession of loud, percussive,
and somewhat jarring cries; these he utters in a leisurely
manner, and immediately after goes on feeding-
Biography of the
Vizcacha. 307
Often he utters this
cry in a low grunting tone. One of his commonest expressions
sounds like the violent hawking of a man clearing his throat. At
other times he bursts into piercing tones that may be heard a
mile off, beginning like the excited and quick-repeated squeals
of a young pig, and growing longer, more attenuated, and
quavering towards the end. After retiring alarmed into the
burrows, he repeats at intervals a deep internal moan. All these,
and many other indescribable guttural, sighing, shrill, and deep
tones, are varied a thousand ways in strength and intonation,
according to the age, sex, or emotions of the individual; and I
doubt if there is in the world any other four-footed thing so
loquacious, or with a dialect so extensive. I take great pleasure
in going to some spot where they are abundant, and sitting
quietly to listen to them; for they are holding a perpetual
discussion, all night long, which the presence of a human being
will not interrupt.
At night, when the
vizcachas are all out feeding, in places where they are very
abundant (and in some districts they literally swarm) any very
loud and sudden sound, as the report of a gun, or a clap of
unexpected thunder, will produce a most extraordinary effect. No
sooner has the report broken on the stillness of night than a
perfect storm of cries bursts forth over the surrounding country.
After eight or nine seconds there is in the storm a momentary
hill or pause; and then it breaks forth again, apparently louder
than before. There is so much difference in the tones of
different animals that the cries of individuals close at hand may
be
308 The Natitralist
in La Plata.
distinguished amidst
the roar of blended voices coming from a distance. It sounds as
if thousands and tens of thousands of them were striving to
express every emotion at the highest pitch of their voices; so
that the effect is indescribable, and fills a stranger with
astonishment. Should a gun be fired off several times, their
cries become less each time; and after the third or fourth time
it produces no effect. They have a peculiar, sharp, sudden,
"far-darting" alarm-note when a dog is spied, that is repeated by
all that hear it, and produces an instantaneous panic, sending
every vizcacha flying to his burrow.
But though they
manifest such a terror of dogs when out feeding at night (for the
slowest dog can overtake them), in the evening, when sitting upon
their mounds, they treat them with tantalizing contempt. If the
dog is a novice, the instant he spies the animal he rushes
violently at it; the vizcacha waits the charge with imperturbable
calmness till his enemy is within one or two yards, and then
disappears into the burrow. After having been foiled in this way
many times, the dog resorts to stratagem: he crouches down as if
transformed for the nonce into a Felis, and steals on with
wonderfully slow and cautious steps, his hair bristling, tail
hanging, and eyes intent on his motionless intended victim; when
within seven or eight yards he makes a sudden rush, but
invariably with the same dis-appointing result. The persistence
with which the dogs go on hoping against hope in this
unprofitable game, in which they always act the stupid part, is
highly amusing, and is very interesting to the
Biography of the
Viscacha. 309
naturalist; for it
shows that the native dogs on the pampas have developed a very
remarkable instinct, and one that might be perfected by
artificial selection; but dogs with the hunting habits of the cat
would, I think, be of little use to man. When it is required to
train dogs to hunt the nocturnal armadillo (Dasypus villosus),
then this deep-rooted (and, it might be added, hereditary)
passion for vizcachas is excessively annoying, and it is often
necessary to administer hundreds of blows and rebukes before a
dog is induced to track an armadillo without leaving the scent
every few moments to make futile grabs at his old
enemies.