Chapter 7

But fruit-eating and flower-feeding creatures, like butterflies and humming-birds--seeking their food ever among the bright berries and brilliant flowers, almost invariably acquire in the long run an æsthetic taste for pure and varied colouring, and by the aid of sexual selection this taste stereotypes itself at last in their own wings and plumage. They choose their mates for colour as they choose their foodstuffs. Hence all the larger and more gregarious parrots, in which the need for concealment is less, tend to diversify the fundamental green of their coats with crimson, yellow, or blue, which in some cases take possession of the entire body. The largest kinds of all, like the great blue and yellow or crimson macaws, are as gorgeous as Solomon in all his glory: and they are also the species least afraid of enemies; for in Brazil you may often see them wending their way homeward openly in pairs every evening, with as little attempt at concealment as rooks in England. In the Moluccas and New Guinea, says Mr. Wallace, white cockatoos and gorgeous lories in crimson and blue are the very commonest objects in the local fauna. Even the New Zealand owl-parrot, however, still retains many traces of his original greenness, mixed with the dirty brown and dingy yellow of his acquired nocturnal and burrowing nature.

If fruit-eaters are fine, flower-haunters are magnificent. And the brush-tongued lories, that search for nectar among the bells of Malayan blossoms, are the brightest-coloured of all the parrot tribes. Indeed, no group of birds, according to Mr. Alfred Russel Wallace (who ought to know, if anybody does), exhibits within the same limited number of types so extraordinary a diversity and richness of colouring as the parrots. 'As a rule,' he says, 'parrots may be termed green birds, the majority of the species having this colour as the basis of their plumage, relieved by caps, gorgets, bands and wing-spots of other and brighter hues. Yet this general green tint sometimes changes into light or deep blue, as in some macaws; into pure yellow or rich orange, as in some of the American macaw-parrots; into purple, grey or dove-colour, as in some American, African, and Indian species; into the purest crimson, as in some of the lories; into rosy-white and pure white, as in the cockatoos; and into a deep purple, ashy or black, as in several Papuan, Australian, and Mascarene species. There is in fact hardly a single distinct and definable colour that cannot be fairly matched among the 390 species of known parrots. Their habits, too, are such as to bring them prominently before the eye. They usually feed in flocks; they are noisy, and so attract attention; they love gardens, orchards, and open sunny places; they wander about far in search of food, and towards sunset return homeward in noisy flocks, or in constant pairs. Their forms and motions are often beautiful and attractive. The immensely long tails of the macaws and the more slender tails of the Indian parroquets, the fine crest of the cockatoos, the swift flight of many of the smaller species, and the graceful motions of the little love-birds and allied forms, together with their affectionate natures, aptitude for domestication, and power of mimicry, combine to render them at once the most conspicuous and the most attractive of all the specially tropical forms of bird life.'

I have purposely left to the last the one point about parrots which most often attracts the attention of the young, the gay, the giddy, and the thoughtless: I mean their power of mimicry in human language. And I believe I am justified in passing it over lightly. For in fact this power is but a very incidental result of the general intelligence of parrots, combined with the other peculiarities of their social life and forestine character. Dominant woodland animals, indeed, like monkeys, parrots, toucans, and hornbills, at least if vegetarian in their habits, are almost always gregarious, noisy, mischievous, and imitative. And the imitation results directly from the unusual intelligence; for, after all, what is the power of learning itself--at least, in all save its very highest phases--but the faculty of accurately imitating another? Monkeys for the most part imitate action only, because they haven't very varied or flexible voices. Parrots and many other birds, on the contrary--like the starling and still more markedly the American mocking-bird--being endowed with considerable flexibility of voice, imitate either songs or spoken words with great distinctness. In the parrot the power of attention is also very considerable, for the bird will often try over with itself repeatedly the lesson it has set itself to learn. But people too generally forget that at best the parrot knows only the general application of a sentence, not the separate meanings of its component words. It knows, for example, that 'Polly wants a lump of sugar' is a phrase often followed by a present of food. But to believe it can understand an abstract expression, like the famous 'By Jove! what a beastly lot of parrots!' is to confound learning by rote with genuine comprehension. A careful review of all the evidence makes almost every scientific observer conclude that at most a parrot knows a word of command as a horse knows 'Whoa!' or a dog knows the order to hunt for rats in the wainscot.

HIGH LIFE.

Everybody knows mountain flowers are beautiful. As one rises up any minor height in the Alps or the Pyrenees below snow-level, one notices at once the extraordinary brilliancy and richness of the blossoms one meets there. All nature is dressed in its brightest robes. Great belts of blue gentian hang like a zone on the mountain slopes; masses of yellow globe-flower star the upland pastures; nodding heads of soldanella lurk low among the rugged boulders by the glacier's side. No lowland blossoms have such vividness of colouring, or grow in such conspicuous patches. To strike the eye from afar, to attract and allure at a distance, is the great aim and end in life of the Alpine flora.

Now, why are Alpine plants so anxious to be seen of men and angels? Why do they flaunt their golden glories so openly before the world, instead of shrinking in modest reserve beneath their own green leaves, like the Puritan primrose and the retiring violet? The answer is, Because of the extreme rarity of the mountain air. It's the barometer that does it. At first sight, I will readily admit, this explanation seems as fanciful as the traditional connection between Goodwin Sands and Tenterden Steeple. But, like the amateur stories in country papers, it is 'founded on fact,' for all that. (Imagine, by the way, a tale founded entirely on fiction! How charmingly aerial!) By a roundabout road, through varying chains of cause and effect, the rarity of the air does really account in the long run for the beauty and conspicuousness of the mountain flowers.

For bees, the common go-betweens of the loves of the plants, cease to range about a thousand or fifteen hundred feet below snow-level. And why? Because it's too cold for them? Oh, dear, no: on sunny days in early English spring, when the thermometer doesn't rise above freezing in the shade, you will see both the honey-bees and the great black bumble as busy as their conventional character demands of them among the golden cups of the first timid crocuses. Give the bee sunshine, indeed, with a temperature just about freezing-point, and he'll flit about joyously on his communistic errand. But bees, one must remember, have heavy bodies and relatively small wings: in the rarefied air of mountain heights they can't manage to support themselves in the most literal sense. Hence their place in these high stations of the world is taken by the gay and airy butterflies, which have lighter bodies and a much bigger expanse of wing-area to buoy them up. In the valleys and plains the bee competes at an advantage with the butterflies for all the sweets of life: but in this broad sub-glacial belt on the mountain-sides the butterflies in turn have things all their own way. They flit about like monarchs of all they survey, without a rival in the world to dispute their supremacy.

And how does the preponderance of butterflies in the upper regions of the air affect the colour and brilliancy of the flowers? Simply thus. Bees, as we are all aware on the authority of the great Dr. Watts, are industrious creatures which employ each shining hour (well-chosen epithet, 'shining') for the good of the community, and to the best purpose. The bee, in fact, is the _bon bourgeois_ of the insect world: he attends strictly to business, loses no time in wild or reckless excursions, and flies by the straightest path from flower to flower of the same species with mathematical precision. Moreover, he is careful, cautious, observant, and steady-going--a model business man, in fact, of sound middle-class morals and sober middle-class intelligence. No flitting for him, no coquetting, no fickleness. Therefore, the flowers that have adapted themselves to his needs, and that depend upon him mainly or solely for fertilisation, waste no unnecessary material on those big flaunting coloured posters which we human observers know as petals. They have, for the most part, simple blue or purple flowers, tubular in shape and, individually, inconspicuous in hue; and they are oftenest arranged in long spikes of blossom to avoid wasting the time of their winged Mr. Bultitudes. So long as they are just bright enough to catch the bee's eye a few yards away, they are certain to receive a visit in due season from that industrious and persistent commercial traveller. Having a circle of good customers upon whom they can depend with certainty for fertilisation, they have no need to waste any large proportion of their substance upon expensive advertisements or gaudy petals.

It is just the opposite with butterflies. Those gay and irrepressible creatures, the fashionable and frivolous element in the insect world, gad about from flower to flower over great distances at once, and think much more of sunning themselves and of attracting their fellows than of attention to business. And the reason is obvious, if one considers for a moment the difference in the political and domestic economy of the two opposed groups. For the honey-bees are neuters, sexless purveyors of the hive, with no interest on earth save the storing of honey for the common benefit of the phalanstery to which they belong. But the butterflies are full-fledged males and females, on the hunt through the world for suitable partners: they think far less of feeding than of displaying their charms: a little honey to support them during their flight is all they need:--'For the bee, a long round of ceaseless toil; for me,' says the gay butterfly, 'a short life and a merry one.' Mr. Harold Skimpole needed only 'music, sunshine, a few grapes.' The butterflies are of his kind. The high mountain zone is for them a true ball-room: the flowers are light refreshments laid out in the vestibule. Their real business in life is not to gorge and lay by, but to coquette and display themselves and find fitting partners.

So while the bees with their honey-bags, like the financier with his money-bags, are storing up profit for the composite community, the butterfly, on the contrary, lays himself out for an agreeable flutter, and sips nectar where he will, over large areas of country. He flies rather high, flaunting his wings in the sun, because he wants to show himself off in all his airy beauty: and when he spies a bed of bright flowers afar off on the sun-smitten slopes, he sails off towards them lazily, like a grand signior who amuses himself. No regular plodding through a monotonous spike of plain little bells for him: what he wants is brilliant colour, bold advertisement, good honey, and plenty of it. He doesn't care to search. Who wants his favours must make himself conspicuous.

Now, plants are good shopkeepers; they lay themselves out strictly to attract their customers. Hence the character of the flowers on this beeless belt of mountain side is entirely determined by the character of the butterfly fertilisers. Only those plants which laid themselves out from time immemorial to suit the butterflies, in other words, have succeeded in the long run in the struggle for existence. So the butterfly-plants of the butterfly-zone are all strictly adapted to butterfly tastes and butterfly fancies. They are, for the most part, individually large and brilliantly coloured: they have lots of honey, often stored at the base of a deep and open bell which the long proboscis of the insect can easily penetrate: and they habitually grow close together in broad belts or patches, so that the colour of each reinforces and aids the colour of the others. It is this cumulative habit that accounts for the marked flowerbed or jam-tart character which everybody must have noticed in the high Alpine flora.

Aristocracies usually pride themselves on their antiquity: and the high life of the mountains is undeniably ancient. The plants and animals of the butterfly-zone belong to a special group which appears everywhere in Europe and America about the limit of snow, whether northward or upward. For example, I was pleased to note near the summit of Mount Washington (the highest peak in New Hampshire) that a large number of the flowers belonged to species well known on the open plains of Lapland and Finland. The plants of the High Alps are found also, as a rule, not only on the High Pyrenees, the Carpathians, the Scotch Grampians, and the Norwegian fjelds, but also round the Arctic Circle in Europe and America. They reappear at long distances where suitable conditions recur: they follow the snow-line as the snow-line recedes ever in summer higher north toward the pole or higher vertically toward the mountain summits. And this bespeaks in one way to the reasoning mind a very ancient ancestry. It shows they date back to a very old and cold epoch.

Let me give a single instance which strikingly illustrates the general principle. Near the top of Mount Washington, as aforesaid, lives to this day a little colony of very cold-loving and mountainous butterflies, which never descend below a couple of thousand feet from the wind-swept summit. Except just there, there are no more of there sort anywhere about: and as far as the butterflies themselves are aware, no others of their species exist on earth: they never have seen a single one of their kind, save of their own little colony. One might compare them with the Pitcairn Islanders in the South Seas--an isolated group of English origin, cut off by a vast distance from all their congeners in Europe or America. But if you go north some eight or nine hundred miles from New Hampshire to Labrador, at a certain point the same butterfly reappears, and spreads northward toward the pole in great abundance. Now, how did this little colony of chilly insects get separated from the main body, and islanded, as it were, on a remote mountain-top in far warmer New Hampshire?

The answer is, they were stranded there at the end of the Glacial epoch.

A couple of hundred thousand years ago or thereabouts--don't let us haggle, I beg of you, over a few casual centuries--the whole of northern Europe and America was covered from end to end, as everybody knows, by a sheet of solid ice, like the one which Frithiof Nansen crossed from sea to sea on his own account in Greenland. For many thousand years, with occasional warmer spells, that vast ice-sheet brooded, silent and grim, over the face of the two continents. Life was extinct as far south as the latitude of New York and London. No plant or animal survived the general freezing. Not a creature broke the monotony of that endless glacial desert. At last, as the celestial cycle came round in due season, fresh conditions supervened. Warmer weather set in, and the ice began to melt. Then the plants and animals of the sub-glacial district were pushed slowly northward by the warmth after the retreating ice-cap. As time went on, the climate of the plains got too hot to hold them. The summer was too much for the glacial types to endure. They remained only on the highest mountain peaks or close to the southern limit of eternal snow. In this way, every isolated range in either continent has its own little colony of arctic or glacial plants and animals, which still survive by themselves, unaffected by intercourse with their unknown and unsuspected fellow-creatures elsewhere.

Not only has the Glacial epoch left these organic traces of its existence, however; in some parts of New Hampshire, where the glaciers were unusually thick and deep, fragments of the primæval ice itself still remain on the spots where they were originally stranded. Among the shady glens of the white mountains there occur here and there great masses of ancient ice, the unmelted remnant of primæval glaciers; and one of these is so large that an artificial cave has been cleverly excavated in it, as an attraction for tourists, by the canny Yankee proprietor. Elsewhere the old ice-blocks are buried under the _débris_ of moraine-stuff and alluvium, and are only accidentally discovered by the sinking of what are locally known as ice-wells. No existing conditions can account for the formation of such solid rocks of ice at such a depth in the soil. They are essentially glacier-like in origin and character: they result from the pressure of snow into a crystalline mass in a mountain valley: and they must have remained there unmelted ever since the close of the Glacial epoch, which, by Dr. Croll's calculations, must most probably have ceased to plague our earth some eighty thousand years ago. Modern America, however, has no respect for antiquity: and it is at present engaged in using up this palæocrystic deposit--this belated storehouse of prehistoric ice--in the manufacture of gin slings and brandy cocktails.

As one scales a mountain of moderate height--say seven or eight thousand feet--in a temperate climate, one is sure to be struck by the gradual diminution as one goes in the size of the trees, till at last they tail off into mere shrubs and bushes. This diminution--an old commonplace of tourists--is a marked characteristic of mountain plants, and it depends, of course, in the main upon the effect of cold, and of the wind in winter. Cold, however, is by far the more potent factor of the two, though it is the least often insisted upon: and this can be seen in a moment by anyone who remembers that trees shade off in just the self-same manner near the southern limit of permanent snow in the Arctic regions. And the way the cold acts is simply this: it nips off the young buds in spring in exposed situations, as the chilly sea-breeze does with coast plants, which, as we commonly but incorrectly say, are "blown sideways" from seaward.

Of course, the lower down one gets, and the nearer to the soil, the warmer the layer of air becomes, both because there is greater radiation, and because one can secure a little more shelter. So, very far north, and very near the snow-line on mountains, you always find the vegetation runs low and stunted. It takes advantage of every crack, every cranny in the rocks, every sunny little nook, every jutting point or wee promontory of shelter. And as the mountain plants have been accustomed for ages to the strenuous conditions of such cold and wind-swept situations, they have ended, of course, by adapting themselves to that station in life to which it has pleased the powers that be to call them. They grow quite naturally low and stumpy and rosette-shaped: they are compact of form and very hard of fibre: they present no surface of resistance to the wind in any way; rounded and boss-like, they seldom rise above the level of the rooks and stones, whose interstices they occupy. It is this combination of characters that makes mountain plants such favourites with florists: for they possess of themselves that close-grown habit and that rich profusion of clustered flowers which it is the grand object of the gardener by artificial selection to produce and encourage.

When one talks of the 'the limit of trees' on a mountain side, however, it must be remembered that the phrase is used in a strictly human or Pickwickian sense, and that it is only the size, not the type, of the vegetation that is really in question. For trees exist even on the highest hill-tops: only they have accommodated themselves to the exigencies of the situation. Smaller and ever smaller species have been developed by natural selection to suit the peculiarities of these inclement spots. Take, for example, the willow and poplar group. Nobody would deny that a weeping willow by an English river, or a Lombardy poplar in an Italian avenue, was as much of a true tree as an oak or a chestnut. But as one mounts towards the bare and wind-swept mountain heights one finds that the willows begin to grow downward gradually. The 'netted willow' of the Alps and Pyrenees, which shelters itself under the lee of little jutting rocks, attains the height of only a few inches; while the 'herbaceous willow,' common on all very high mountains in Western Europe, is a tiny creeping weed, which nobody would ever take for a forest tree by origin at all, unless he happened to see it in the catkin-bearing stage, when its true nature and history would become at once apparent to him.

Yet this little herb-like willow, one of the most northerly and hardy of European plants, is a true tree at heart none the less for all that. Soft and succulent as it looks in branch and leaf, you may yet count on it sometimes as many rings of annual growth as on a lordly Scotch fir-tree. But where? Why, underground. For see how cunning it is, this little stunted descendant of proud forest lords: hard-pressed by nature, it has learnt to make the best of its difficult and precarious position. It has a woody trunk at core, like all other trees; but this trunk never appears above the level of the soil: it creeps and roots underground in tortuous zigzags between the crags and boulders that lie strewn through its thin sheet of upland leaf-mould. By this simple plan the willow manages to get protection in winter, on the same principle as when we human gardeners lay down the stems of vines: only the willow remains laid down all the year and always. But in summer it sends up its short-lived herbaceous branches, covered with tiny green leaves, and ending at last in a single silky catkin. Yet between the great weeping willow and this last degraded mountain representative of the same primitive type, you can trace in Europe alone at least a dozen distinct intermediate forms, all well marked in their differences, and all progressively dwarfed by long stress of unfavourable conditions.