Science in Arcady

by Grant Allen

Still, there are parrots and parrots, of course. Not all this vast family are in all things of like passions one with another. The great black cockatoo, for example, the largest of the tribe, lives almost entirely off the central shoot or 'cabbage' of palm-trees: an expensive kind of food, for when once the 'cabbage' is eaten the tree dies forthwith, so that each black cockatoo must have killed in his time whole groves of cabbage-palms. Others, again, feed off fruits and seeds; and not a few are entirely adapted for flower-haunting and honey-sucking.

As a group, the parrots are comparatively modern birds. Indeed, they could have no place in the world till the big tropical fruits and nuts were beginning to be developed. And it is now pretty certain that fruits and nuts are for the most part of very recent and special evolution. To put it briefly, the monkeys and parrots developed the fruits and nuts, while the fruits and nuts returned the compliment by developing conversely the monkeys and parrots. In other words, both types grew up side by side in mutual dependence, and evolved themselves pari passu for one another's benefit. Without the fruits there could be no fruit-eaters; and without the fruit-eaters to disperse their seeds, there could just to the same extent be no fruits to speak of.

Most of the parrots very much resemble the monkeys and other tropical fruit-feeders in their habits and manners. They are gregarious, mischievous, noisy, and irresponsible. They have no moral sense, and are fond of practical jokes and other schoolboy horseplay. They move about in flocks, screeching aloud as they go, and alight together on some tree well covered with berries. No doubt, they herd together for the sake of protection and screech both to keep the flock in a body and to strike alarm and consternation into the breasts of their enemies. When danger threatens, the first bird that perceives it sounds a note of warning; and in a moment the whole troop is on the wing at once, vociferous and eager, roaring forth a song in their own tongue which may be roughly interpreted as stating in English that they don't want to fight, but by Jingo, if they do, they'll tear their enemy to shreds and drink his blood up too.

The common grey parrot, the best known in confinement of all his kind, and unrivalled as an orator for his graces of speech, is a native of West Africa; so that he shares with other West Africans that perfect command of language which has always been a marked characteristic of the negro race. He feeds in a general way upon palm-nuts, bananas, mangoes, and guavas, but he is by no means averse, if opportunity offers, to the Indian corn of the industrious native. His wife accompanies him in his solitary rambles, for they are not gregarious. In her native haunts, indeed, Polly is an unsociable bird. It is only in confinement that her finer qualities come out, and that she develops into a speech-maker of distinguished attainments.

A very peculiar and exceptional offshoot of the parrot group is the brush-tongued lory, several species of which are common in Australia, India, and the Molucca Islands. These pretty and interesting creatures are in point of fact parrots which have practically made themselves into humming-birds by long continuance in the poetical habit of visiting flowers for food. Like Mr. Oscar Wilde in his æsthetic days, they breakfast off a lily. Flitting about from tree to tree with great rapidity, they thrust their long extensible tongues, pencilled with honey-gathering hairs, into the tubes of many big tropical blossoms. The lories, indeed, live entirely on nectar, and they are so common in the region they have made their own that all the larger flowers there have been developed with a special view to their tastes and habits, as well as to the structure of their peculiar brush-like honey-collector. In most parrots the mouth is dry and the tongue horny; but in the lories it is moist and much more like the same organ in the humming-birds and sun-birds. The prevalence of very large and brilliantly coloured flowers in the Malayan region must be set down for the most part to the selective action of these æsthetic and colour-loving little brush-tongued parrots.

Australia and New Zealand, as everybody knows, are the countries where everything goes by contraries. And it is here that the parrot group has developed some of its strangest and most abnormal offshoots. One would imagine beforehand that no two birds could be more unlike in every respect than the gaudy, noisy, gregarious cockatoos and the sombre, nocturnal, solitary owls. Yet the New Zealand owl-parrot is, to put it plainly, a lory which has assumed all the outer appearance and habits of an owl. A lurker in the twilight or under the shades of night, burrowing for its nest in holes in the ground, it has dingy brown plumage like the owls, with an undertone of green to bespeak its parrot origin: while its face is entirely made up of two great disks, surrounding the eyes, which succeed in giving it a most marked and unmistakable owl-like appearance.

Now, why should a parrot so strangely disguise itself and belie its ancestry? The reason is plain. It found a place for it ready made in nature. New Zealand is a remote and sparsely-stocked island, peopled by mere casual waifs and strays of life from adjacent but still very distant continents. There are no dangerous enemies there. Here, then, was a clear chance for a nightly prowler. The owl-parrot with true business instinct saw the opening thus clearly laid before it, and took to a nocturnal and burrowing life, with the natural consequence that it acquired in time the dingy plumage, crepuscular eyes, and broad disk-like reflectors of other prowling night-fliers. Unlike the owls, however, the owl-parrot, true to the vegetarian instincts of the whole lory race, lives almost entirely upon sprigs of mosses and other creeping plants. It is thus essentially a ground bird; and as it feeds at night in a country possessing no native beasts of prey, it has almost lost the power of flight, and uses its wings only as a sort of parachute to break its fall in descending from a rock or tree to its accustomed feeding-ground. To get up again, it climbs, parrot-like, with its hooked claws, up the surface of the trunk or the face of a precipice.

Even more aberrant in its ways, however, than the burrowing owl-parrot, is that other strange and hated New Zealand lory, the kea, which, alone among its kind, has abjured the gentle ancestral vegetarianism of the cockatoos and macaws, in favour of a carnivorous diet of singular ferocity. And what is odder still, this evil habit has been developed in the kea since the colonization of New Zealand by the English, those most demoralizing of new-comers. The settlers have taught the Maori to wear tall hats and to drink strong liquors: and they have thrown temptation in the way of even the once innocent native parrot. Before the white man came, in fact, the kea was a mild-mannered fruit-eating or honey-sucking bird. But as soon as sheep-stations were established in the island these degenerate parrots began to acquire a distinct taste for raw mutton. At first, to be sure, they ate only the sheep's heads and offal that were thrown out from the slaughter-houses picking the bones as clean of meat as a dog or a jackal. But in process of time, as the taste for blood grew upon them, a still viler idea entered into their wicked heads. The first step on the downward path suggested the second. If dead sheep are good to eat, why not also living ones? The kea, pondering deeply on this abstruse problem, solved it at once with an emphatic affirmative. And he straightway proceeded to act upon his convictions, and invent a really hideous mode of procedure. Perching on the backs of the living sheep he has now learnt the exact spot where the kidneys are to be found; and he tears open the flesh to get at these dainty morsels, which he pulls out and devours, leaving the unhappy animal to die in miserable agony. As many as two hundred ewes have thus been killed in a night at a single station. I need hardly add that the sheep-farmer naturally resents this irregular proceeding, so opposed to all ideals of good grazing, and that the days of the kea are now numbered in New Zealand. But from the purely psychological point of view the case is an interesting one, as being the best recorded instance of the growth of a new and complex instinct actually under the eyes of human observers.

One word as to the general colouring of the parrot group as a whole. Tropical forestine birds have usually a ground tone of green because that colour enables them best to escape notice among the monotonous verdure of equatorial woodland scenery. In the north, to be sure, green is a very conspicuous colour; but that is only because for half the year our trees are bare, and even during the other half they lack that 'breadth of tropic shade' which characterises the forests of all hot countries. Therefore, in temperate climates, the common ground-tone of birds is brown, to harmonise with the bare boughs and leafless twigs, the clods of earth and dead turf or stubble. But in the evergreen tropics green is the right hue for concealment or defence. Therefore the parrots, the most purely tropical family of birds on earth, are mostly greenish; and among the smaller and more defenceless sorts, like the familiar little love-birds, where the need for protection is greatest, the green of the plumage is almost unbroken. Of the tiny Pigmy Parrots of New Guinea, for instance, Mr. Bowdler Sharpe says: 'Owing to their small size and the resemblance of their green colouring to the forests they inhabit, they are not easily seen, and until recent years were very hard to procure.' And of the green parrot of Jamaica, Mr. Gosse remarks: 'Often we hear their voices proceeding from a certain tree, or else have marked the descent of a flock on it; but on proceeding to the spot, though the eye has not wandered from it, we cannot discover an individual. We go close to the tree, but all is silent and still as death. We institute a careful survey of every part with the eye, to detect the slightest motion, or the form of a bird among the leaves, but all in vain. We begin to think they have stolen off unperceived; but on throwing a stone into the tree, a dozen throats burst forth into a cry, and as many green birds rush forth upon the wing. Green may thus be regarded as the normal or basal parrot tint, from which all other colours are special decorative variations.

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.