HOW ANIMALS LEARNT TO CLIMB.
AMONG the forest tribes of India there is one "parish 4 which elects its chief on principles not mentioned in the most exhaustive treatise on "village communities." It is set deep in the forest, and in the centre of the clearing stan,23 one enormous tree, with a branchless trunk running up straight for some 150 ft. This giant tree supplies what may be called the communal fund of the tribe, for among its branches the wild bees have built their combs for generations, and as the tree and the village grow older together, and the claimants on the fund increase, so do the number and weight of the combs from the labour of the procreant bees. The only human work needed to gather the harvest of wax—the honey they value little—is that required to climb the towering tree, and when once there, to smoke the bees and shake down the wax. Consequently, the election of the headman is determined in the first instance by his skill as a climber; and though after election he usually succeeds in investing his office with religious or magical sanctions, and endeavours to bequeath it to his son, there is no reason why the post should not be put up to free competition, and awarded, at least in its qualifying stages, to the man who " did " the tree in the best time on record.
Climbing runs in families, for steeplejacks are often the sons of fathers who were in the business ; but it is somewhat odd that man, though he learns to swim so well that armed only with a knife he can encounter a shark in its native element, and judged by the extent of his mining operations in comparison with the size of his body surpasses by a thousand times all animals that work underground, has never become a good climber, or known the slightest tendency to become "arboreal," as he has become aquatic and subterranean. South Sea babies which cannot walk will roll into the sea and swim, collier boys at fourteen will take pick and lamp and descend into the mine almost as naturally as young moles; but we believe that, in spite of the danger from wild beasts in forest regions, and the fact that in such places there is ten times more life on the level of the tree-tops than on the ground, there is no single instance of a tribe which, properly speaking, has become "arboreal" and learnt to climb like monkeys. Though not a few make huts in trees, they approach these by ladders; and except in the huts which they use as a refuge and sleeping place, they spend their time on the ground. Even in forests where the upper levels of the trees are so closely laced together that a comparatively slight adaptation would enable the Indians to progress from tree to tree, and where nearly the whole of the fruit, and the greater part of the birds and animals, used for food are found only in this "upper story," man is not, and always refuses to be- come, a "climbing animaL" Natural repugnance to this form of enterprise seems characteristic of savage men, and even of animals which run no risks whatever. African natives who have only lived in one-storied huts show the greatest dislike to going up stairs, and have been known to creep up on hands and knees, while large dogs when required to ascend stairs for the first time often refuse to do so except under strong persuasion and with evident reluctance. A half. bred greyhound, now immortalised in a well-known statue of Artemis, would refuse absolutely to descend the stairs when he had once gone up, and had to be carried down. In the case of the dog this dislike to the very modified form of climbing needed for ascending a staircase can be accounted for on physical grounds. A very slight fall, even a jump from a cart, will snap a dog's fore-leg below the shoulder, and they seem aware of the danger. A fox has not the slightest dis- inclination to run these risks ; it climbs easily and leaps down lightly, and though not equipped like a cat for " swarming " a trunk, one was seen by Mr. Tom Smith, when Master of the Craven bounds, sitting at a height of 17 ft. in a straight. stemmed beech-tree with only small horizontal branches to aid the climb.
That this art was acquired by animals with far greater difficulty and effort than that of swimming is evident by the limited number in the same class which have managed to become expert climbers. All the rodents, including even the guinea-pig, are good swimmers. The number which can climb is far more limited, and the line seems drawn not by lack of physical equipment, but by lack of experience, or possibly of the desire to do so. There is, for instance, a regular series, from the tree squirrels through the "ground squirrels" to the prairie-doge and marmots, of very closely allied rodents. The squirrels are at the head of the second rank of climbers, though the lack of "swinging power" in their arms puts them below the monkeys. The "ground squirrels" can climb trees well enough, though they are terrestrial. But the prairie-dogs and marmots, though the former are almost as well equipped for climbing as a rat, have never properly learnt the art, and though not afraid to try, the former come to most lamentable grief in their experiments. Probably the prairie-dogs, which live mainly on level and treeless plains, never had occasion in their lives either to jump or to climb. When loose in a house they try to do both. Being well equipped with claws, and very active, they manage the climb- ing well enough. But as they have never learnt either to jump or to judge distance, or that smooth upright surfaces offer no hold on alighting, they generally miss their jump, and fall violently to the ground. This would not matter, were it not that, as they have large and heavy heads, they usually fall on these, and either stun themselves or break their teeth. This instance of climbing in the experimental stage would be more interesting did we know how the Australian rabbits first learnt to climb, and whether they in- curred similar failures and accidents. There is no doubt that the great difficulty of the second stage of their acquirement of the art was to learn how to climb down again. Some climbing animals have even now not learnt to come down properly, though adepts at climbing up. The bear always descends a vertical trunk "stern foremost," just as a man does; so do some of the opossums, the racoon (generally),
and the domestic cat, though a leopard will run down a vertical trunk with no more hesitation than a nuthatch would show. A frightened cat will run up into a position from which it cannot descend at all, either among the small branches of a tree or on buildings.
Lateral movement in trees is for all animals a far more difficult feat than vertical ascent or descent. Unless the boughs of one tree touch those of another, the creature must learn to jump, with the certainty of a fall if it misses, either on alighting or in " taking off." The " take off " is, we believe, the main difficulty. Except in the case of the tree-kangaroo, some considerable modification of the hind-foot into some. thing like the palm of a hand, or an equipment of sharp claws, to act like the nails in an Alpine climber's boot and prevent slipping, is usual in the creatures which excel in lateral climbing. The cat and the bear, the lynx, stoat, ferret, and rat are all as yet imperfect in this branch of their business. The marten, on the other hand, excels even the squirrel in this acrobatic feat, for the squirrel naturally seeks to escape the marten or sable in this way, yet these small carnivora make the squirrel their principal food. Tigers probably refuse to climb because their weight is so great as to make any fall dangerous to a limb. The bears, of which the grizzly climbs little, would run the same danger had not they acquired a special facility for rolling up first their limbs, and then their bodies, into some- thing like the initial curve of a collapsing hedgehog, which preserves the bones from injury. A bear will volun. tarily roll over almost precipitous rocks and pick itself up at the bottom no worse for its fall. No animal with hoofs can climb a tree, though a goat very nearly succeeds in this, and the writer has seen a pig climb out of a stye over a paling of boards 6 ft. high, with interstices between each of the boards, and three cross pieces of wood. The pig scrambled up just as a dog might, and when the fore-feet were over the top of the fence gave itself a hoist and a wriggle, and rolled over, dropping on its feet. The climbing birds seem past masters of their business, with the exception of some of the parrots. These are clearly not yet fully accustomed to the work ; for every grey parrot climbs with the aid of its beak; and so dependent is it on this that even when crawling on the ground a parrot will pull itself along from one projection or piece of furniture to another by laying hold with its bill.
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