Part 2 (1/2)

21. Brehm, iv. 671 seq.

22. R. Lendenfeld, in Der zoologische Garten, 1889.

CHAPTER II

MUTUAL AID AMONG ANIMALS (continued)

Migrations of birds. Breeding a.s.sociations. Autumn societies. Mammals: small number of unsociable species. Hunting a.s.sociations of wolves, lions, etc. Societies of rodents; of ruminants; of monkeys. Mutual Aid in the struggle for life. Darwin's arguments to prove the struggle for life within the species. Natural checks to over-multiplication. Supposed extermination of intermediate links. Elimination of compet.i.tion in Nature.

As soon as spring comes back to the temperate zone, myriads and myriads of birds which are scattered over the warmer regions of the South come together in numberless bands, and, full of vigour and joy, hasten northwards to rear their offspring. Each of our hedges, each grove, each ocean cliff, and each of the lakes and ponds with which Northern America, Northern Europe, and Northern Asia are dotted tell us at that time of the year the tale of what mutual aid means for the birds; what force, energy, and protection it confers to every living being, however feeble and defenceless it otherwise might be. Take, for instance, one of the numberless lakes of the Russian and Siberian Steppes. Its sh.o.r.es are peopled with myriads of aquatic birds, belonging to at least a score of different species, all living in perfect peace--all protecting one another.

”For several hundred yards from the sh.o.r.e the air is filled with gulls and terns, as with snow-flakes on a winter day. Thousands of plovers and sand-coursers run over the beach, searching their food, whistling, and simply enjoying life. Further on, on almost each wave, a duck is rocking, while higher up you notice the flocks of the Casarki ducks.

Exuberant life swarms everywhere.”(1)

And here are the robbers--the strongest, the most cunning ones, those ”ideally organized for robbery.” And you hear their hungry, angry, dismal cries as for hours in succession they watch the opportunity of s.n.a.t.c.hing from this ma.s.s of living beings one single unprotected individual. But as soon as they approach, their presence is signalled by dozens of voluntary sentries, and hundreds of gulls and terns set to chase the robber. Maddened by hunger, the robber soon abandons his usual precautions: he suddenly dashes into the living ma.s.s; but, attacked from all sides, he again is compelled to retreat. From sheer despair he falls upon the wild ducks; but the intelligent, social birds rapidly gather in a flock and fly away if the robber is an erne; they plunge into the lake if it is a falcon; or they raise a cloud of water-dust and bewilder the a.s.sailant if it is a kite.(2) And while life continues to swarm on the lake, the robber flies away with cries of anger, and looks out for carrion, or for a young bird or a field-mouse not yet used to obey in time the warnings of its comrades. In the face of an exuberant life, the ideally-armed robber must be satisfied with the off-fall of that life.

Further north, in the Arctic archipelagoes,

”you may sail along the coast for many miles and see all the ledges, all the cliffs and corners of the mountain-sides, up to a height of from two to five hundred feet, literally covered with sea-birds, whose white b.r.e.a.s.t.s show against the dark rocks as if the rocks were closely sprinkled with chalk specks. The air, near and far, is, so to say, full with fowls.”(3)

Each of such ”bird-mountains” is a living ill.u.s.tration of mutual aid, as well as of the infinite variety of characters, individual and specific, resulting from social life. The oyster-catcher is renowned for its readiness to attack the birds of prey. The barge is known for its watchfulness, and it easily becomes the leader of more placid birds. The turnstone, when surrounded by comrades belonging to more energetic species, is a rather timorous bird; but it undertakes to keep watch for the security of the commonwealth when surrounded by smaller birds. Here you have the dominative swans; there, the extremely sociable kittiwake-gulls, among whom quarrels are rare and short; the prepossessing polar guillemots, which continually caress each other; the egoist she-goose, who has repudiated the orphans of a killed comrade; and, by her side, another female who adopts any one's orphans, and now paddles surrounded by fifty or sixty youngsters, whom she conducts and cares for as if they all were her own breed. Side by side with the penguins, which steal one another's eggs, you have the dotterels, whose family relations are so ”charming and touching” that even pa.s.sionate hunters recoil from shooting a female surrounded by her young ones; or the eider-ducks, among which (like the velvet-ducks, or the coroyas of the Savannahs) several females hatch together in the same nest, or the lums, which sit in turn upon a common covey. Nature is variety itself, offering all possible varieties of characters, from the basest to the highest: and that is why she cannot be depicted by any sweeping a.s.sertion. Still less can she be judged from the moralist's point of view, because the views of the moralist are themselves a result--mostly unconscious--of the observation of Nature.

Coming together at nesting-time is so common with most birds that more examples are scarcely needed. Our trees are crowned with groups of crows' nests; our hedges are full of nests of smaller birds; our farmhouses give shelter to colonies of swallows; our old towers are the refuge of hundreds of nocturnal birds; and pages might be filled with the most charming descriptions of the peace and harmony which prevail in almost all these nesting a.s.sociations. As to the protection derived by the weakest birds from their unions, it is evident. That excellent observer, Dr. Coues, saw, for instance, the little cliff-swallows nesting in the immediate neighbourhood of the prairie falcon (Falco polyargus). The falcon had its nest on the top of one of the minarets of clay which are so common in the canons of Colorado, while a colony of swallows nested just beneath. The little peaceful birds had no fear of their rapacious neighbour; they never let it approach to their colony.

They immediately surrounded it and chased it, so that it had to make off at once.(4)

Life in societies does not cease when the nesting period is over; it begins then in a new form. The young broods gather in societies of youngsters, generally including several species. Social life is practised at that time chiefly for its own sake--partly for security, but chiefly for the pleasures derived from it. So we see in our forests the societies formed by the young nuthatchers (Sitta caesia), together with t.i.t-mouses, chaffinches, wrens, tree-creepers, or some wood-p.e.c.k.e.rs.(5) In Spain the swallow is met with in company with kestrels, fly-catchers, and even pigeons. In the Far West of America the young horned larks live in large societies, together with another lark (Sprague's), the skylark, the Savannah sparrow, and several species of buntings and longspurs.(6) In fact, it would be much easier to describe the species which live isolated than to simply name those species which join the autumnal societies of young birds--not for hunting or nesting purposes, but simply to enjoy life in society and to spend their time in plays and sports, after having given a few hours every day to find their daily food.

And, finally, we have that immense display of mutual aid among birds-their migrations--which I dare not even enter upon in this place.

Sufficient to say that birds which have lived for months in small bands scattered over a wide territory gather in thousands; they come together at a given place, for several days in succession, before they start, and they evidently discuss the particulars of the journey. Some species will indulge every afternoon in flights preparatory to the long pa.s.sage. All wait for their tardy congeners, and finally they start in a certain well chosen direction--a fruit of acc.u.mulated collective experience--the strongest flying at the head of the band, and relieving one another in that difficult task. They cross the seas in large bands consisting of both big and small birds, and when they return next spring they repair to the same spot, and, in most cases, each of them takes possession of the very same nest which it had built or repaired the previous year.(7)

This subject is so vast, and yet so imperfectly studied; it offers so many striking ill.u.s.trations of mutual-aid habits, subsidiary to the main fact of migration--each of which would, however, require a special study--that I must refrain from entering here into more details. I can only cursorily refer to the numerous and animated gatherings of birds which take place, always on the same spot, before they begin their long journeys north or south, as also those which one sees in the north, after the birds have arrived at their breeding-places on the Yenisei or in the northern counties of England. For many days in succession--sometimes one month--they will come together every morning for one hour, before flying in search of food--perhaps discussing the spot where they are going to build their nests.(8) And if, during the migration, their columns are overtaken by a storm, birds of the most different species will be brought together by common misfortune. The birds which are not exactly migratory, but slowly move northwards and southwards with the seasons, also perform these peregrinations in flocks. So far from migrating isolately, in order to secure for each separate individual the advantages of better food or shelter which are to be found in another district--they always wait for each other, and gather in flocks, before they move north or south, in accordance with the season.(9)

Going now over to mammals, the first thing which strikes us is the overwhelming numerical predominance of social species over those few carnivores which do not a.s.sociate. The plateaus, the Alpine tracts, and the Steppes of the Old and New World are stocked with herds of deer, antelopes, gazelles, fallow deer, buffaloes, wild goats and sheep, all of which are sociable animals. When the Europeans came to settle in America, they found it so densely peopled with buffaloes, that pioneers had to stop their advance when a column of migrating buffaloes came to cross the route they followed; the march past of the dense column lasting sometimes for two and three days. And when the Russians took possession of Siberia they found it so densely peopled with deer, antelopes, squirrels, and other sociable animals, that the very conquest of Siberia was nothing but a hunting expedition which lasted for two hundred years; while the gra.s.s plains of Eastern Africa are still covered with herds composed of zebra, the hartebeest, and other antelopes.

Not long ago the small streams of Northern America and Northern Siberia were peopled with colonies of beavers, and up to the seventeenth century like colonies swarmed in Northern Russia. The flat lands of the four great continents are still covered with countless colonies of mice, ground-squirrels, marmots, and other rodents. In the lower lat.i.tudes of Asia and Africa the forests are still the abode of numerous families of elephants, rhinoceroses, and numberless societies of monkeys. In the far north the reindeer aggregate in numberless herds; while still further north we find the herds of the musk-oxen and numberless bands of polar foxes. The coasts of the ocean are enlivened by flocks of seals and morses; its waters, by shoals of sociable cetaceans; and even in the depths of the great plateau of Central Asia we find herds of wild horses, wild donkeys, wild camels, and wild sheep. All these mammals live in societies and nations sometimes numbering hundreds of thousands of individuals, although now, after three centuries of gunpowder civilization, we find but the debris of the immense aggregations of old.

How trifling, in comparison with them, are the numbers of the carnivores! And how false, therefore, is the view of those who speak of the animal world as if nothing were to be seen in it but lions and hyenas plunging their bleeding teeth into the flesh of their victims!

One might as well imagine that the whole of human life is nothing but a succession of war ma.s.sacres.

a.s.sociation and mutual aid are the rule with mammals. We find social habits even among the carnivores, and we can only name the cat tribe (lions, tigers, leopards, etc.) as a division the members of which decidedly prefer isolation to society, and are but seldom met with even in small groups. And yet, even among lions ”this is a very common practice to hunt in company.”(10) The two tribes of the civets (Viverridae) and the weasels (Mustelidae) might also be characterized by their isolated life, but it is a fact that during the last century the common weasel was more sociable than it is now; it was seen then in larger groups in Scotland and in the Unterwalden canton of Switzerland.

As to the great tribe of the dogs, it is eminently sociable, and a.s.sociation for hunting purposes may be considered as eminently characteristic of its numerous species. It is well known, in fact, that wolves gather in packs for hunting, and Tschudi left an excellent description of how they draw up in a half-circle, surround a cow which is grazing on a mountain slope, and then, suddenly appearing with a loud barking, make it roll in the abyss.(11) Audubon, in the thirties, also saw the Labrador wolves hunting in packs, and one pack following a man to his cabin, and killing the dogs. During severe winters the packs of wolves grow so numerous as to become a danger for human settlements, as was the case in France some five-and-forty years ago. In the Russian Steppes they never attack the horses otherwise than in packs; and yet they have to sustain bitter fights, during which the horses (according to Kohl's testimony) sometimes a.s.sume offensive warfare, and in such cases, if the wolves do not retreat promptly, they run the risk of being surrounded by the horses and killed by their hoofs. The prairie-wolves (Canis latrans) are known to a.s.sociate in bands of from twenty to thirty individuals when they chase a buffalo occasionally separated from its herd.(12) Jackals, which are most courageous and may be considered as one of the most intelligent representatives of the dog tribe, always hunt in packs; thus united, they have no fear of the bigger carnivores.(13) As to the wild dogs of Asia (the Kholzuns, or Dholes), Williamson saw their large packs attacking all larger animals save elephants and rhinoceroses, and overpowering bears and tigers. Hyenas always live in societies and hunt in packs, and the hunting organizations of the painted lycaons are highly praised by c.u.mming. Nay, even foxes, which, as a rule, live isolated in our civilized countries, have been seen combining for hunting purposes.(14) As to the polar fox, it is--or rather was in Steller's time--one of the most sociable animals; and when one reads Steller's description of the war that was waged by Behring's unfortunate crew against these intelligent small animals, one does not know what to wonder at most: the extraordinary intelligence of the foxes and the mutual aid they displayed in digging out food concealed under cairns, or stored upon a pillar (one fox would climb on its top and throw the food to its comrades beneath), or the cruelty of man, driven to despair by the numerous packs of foxes. Even some bears live in societies where they are not disturbed by man. Thus Steller saw the black bear of Kamtchatka in numerous packs, and the polar bears are occasionally found in small groups. Even the unintelligent insectivores do not always disdain a.s.sociation.

However, it is especially with the rodents, the ungulata, and the ruminants that we find a highly developed practice of mutual aid. The squirrels are individualist to a great extent. Each of them builds its own comfortable nest, and acc.u.mulates its own provision. Their inclinations are towards family life, and Brehm found that a family of squirrels is never so happy as when the two broods of the same year can join together with their parents in a remote corner of a forest. And yet they maintain social relations. The inhabitants of the separate nests remain in a close intercourse, and when the pine-cones become rare in the forest they inhabit, they emigrate in bands. As to the black squirrels of the Far West, they are eminently sociable. Apart from the few hours given every day to foraging, they spend their lives in playing in numerous parties. And when they multiply too rapidly in a region, they a.s.semble in bands, almost as numerous as those of locusts, and move southwards, devastating the forests, the fields, and the gardens; while foxes, polecats, falcons, and nocturnal birds of prey follow their thick columns and live upon the individuals remaining behind. The ground-squirrel--a closely-akin genus--is still more sociable. It is given to h.o.a.rding, and stores up in its subterranean halls large amounts of edible roots and nuts, usually plundered by man in the autumn.

According to some observers, it must know something of the joys of a miser. And yet it remains sociable. It always lives in large villages, and Audubon, who opened some dwellings of the hackee in the winter, found several individuals in the same apartment; they must have stored it with common efforts.

The large tribe, of the marmots, which includes the three large genuses of Arctomys, Cynomys, and Spermophilus, is still more sociable and still more intelligent. They also prefer having each one its own dwelling; but they live in big villages. That terrible enemy of the crops of South Russia--the souslik--of which some ten millions are exterminated every year by man alone, lives in numberless colonies; and while the Russian provincial a.s.semblies gravely discuss the means of getting rid of this enemy of society, it enjoys life in its thousands in the most joyful way. Their play is so charming that no observer could refrain from paying them a tribute of praise, and from mentioning the melodious concerts arising from the sharp whistlings of the males and the melancholic whistlings of the females, before--suddenly returning to his citizen's duties--he begins inventing the most diabolic means for the extermination of the little robbers. All kinds of rapacious birds and beasts of prey having proved powerless, the last word of science in this warfare is the inoculation of cholera! The villages of the prairie-dogs in America are one of the loveliest sights. As far as the eye can embrace the prairie, it sees heaps of earth, and on each of them a prairie-dog stands, engaged in a lively conversation with its neighbours by means of short barkings. As soon as the approach of man is signalled, all plunge in a moment into their dwellings; all have disappeared as by enchantment. But if the danger is over, the little creatures soon reappear. Whole families come out of their galleries and indulge in play. The young ones scratch one another, they worry one another, and display their gracefulness while standing upright, and in the meantime the old ones keep watch. They go visiting one another, and the beaten footpaths which connect all their heaps testify to the frequency of the visitations. In short, the best naturalists have written some of their best pages in describing the a.s.sociations of the prairie-dogs of America, the marmots of the Old World, and the polar marmots of the Alpine regions. And yet, I must make, as regards the marmots, the same remark as I have made when speaking of the bees. They have maintained their fighting instincts, and these instincts reappear in captivity. But in their big a.s.sociations, in the face of free Nature, the unsociable instincts have no opportunity to develop, and the general result is peace and harmony.