THE INTELLECTUAL POWERS OF BIRDS.
THE Popular Science Review for July contains some Interesting but too brief remarks by Mr. Leith Adams on the Mental Powers of Birds, which it is interesting to define specifically as distinguished from the mental powers of other animals of the higher order of sagacity. This we will briefly do. First, it would appear from Mr. Darwin's discussions—though Mr. Leith Adams hardly refers to them,—that none of the lower orders of creatures have so keen an appreciation of beauty as many kinds of birds, and certainly that none turn this taste for beauty so deliberately to the purpose of social amusement. That great naturalist has described how some kinds of birds really celebrate festivities very closely approach- ing to our wedding fetes, balls, and garden parties, in places carefully decorated and arranged by the birds for the purpose of social gatherings, and which are not used for their actual dwell- ing-places. The best evidence, says Mr. Darwin, of a taste for the beautiful "is afforded. by the three genera of Australian bower-birds." "Their bowers where the sexes congregate and play strange antics" [2 at all stranger than our waltzes and quadrilles] "are differently constructed ; but what most con- cerns us is that they are decorated in a different manner by the different species. The Satin Bower-bird collects gaily- coloured articles, such as the blue tail-feathers of parrakeets, bleached bones and shells, which it sticks between the twigs, or arranges at the entrance. Mr. Gould found in one bower a neatly- worked stone tomahawk and a slip of blue cotton, evidently prop cured from a native encampment. These objects are continually rearranged and carried about by the birds while at play. The bower of the Spotted Bower-bird is beautifully lined with tall grasses, so disposed that the heads nearly meat, and the decorations are very profuse. Round stones are used to keep the grass-stems in their proper places, and to make divergent paths leading to the bower. The stones and shells are often brought from a great distance. The Regent-bird, as described by Mr. Ramsay, ornaments its short bower with bleached land-shells belonging to five or six species, and.' with berries of various colours, blue, red, and black, which give it, when fresh, a very pretty appearance. Besides these, there were several newly- picked leaves and young shoots of a pinkish colour, the whole showing a decided taste for the beautiful.' Well may Mr. Gould say, 'these highly-decorated halls of assembly must be regarded as the most wonderful instances of bird architecture yet discovered ;' and the taste, we see, of the several species certainly differs." You could not have distincter evidence in a lady's salon carefully decorated with flowers, either of her taste for the beautiful, or of the deliberate subordination of that taste to social purposes, than we have here of the same qualities in birds. Mr. Leith Adams in his paper hardly refers, as we have already observed, to this remarkable class of facts at all, only pointing out that the obvious preference for gaily-coloured plumage on the part of the females clearly implies a genuine taste for the beautiful in birds, which is, of course, true, but is not nearly as good evidence of a distinct intellectual develop- ment on this point, as the elaborate decoration of their bowers
by birds for festive purposes. The mere preference of gay colours may be unconscious and purely instinctive, but when a bird looks out for bleached land-shells and tall grasses to ornament its reception room, and fetches round stones to "fix" the grasses in their proper place, and then uses the hall thus provided only for festive social purposes, you can hardly deny such birds either the powers or the tastes of landscape gardeners and ball-givers. And we fancy this kind of deliberate taste for the beautiful, and the beautiful in subor- dination to social purposes, is confined among the lower animals to birds ; and as regards the social purposes, to a very few orders of birds. A great many birds seem to have more appreciation of beauty of colour than almost any other class of animals, but only in a few species has it risen to the point of a really deco- rative social art. We may gather from this that in the bird the perception of harmony is of a very high kind, and this evidently applies to sound as well as colour. No creatures utter sounds so full of beauty, or display such wonderful qualifications for imitat- ing the beautiful sounds they hear. Must we not say, then, that the bird has, in more force than any other species of the lower animals, the perception of harmony in forms, colours, and sounds, and the further consciousness of the fascination such harmony has for its own species, and the enhancement it lends to social enjoyments.
Another great mental quality which birds seem to have in excess of other animals is a very fine calculation of distance, and this, too, in direct subordination to their own well-being. It has been shown again and again,—and Mr. Leith Adams refers to some facts in support of it in this essay,—that as new weapons of offence are invented, many species of birds narrowly observe the range of the new bows or guns, and keep out of range, not even troubling themselves to go at all farther than is necessary to be out of range. Quite recently we have read, though we cannot verify the reference at present, of some birds which adapted themselves within a few days to the increased range of the rifle, directly after they had learned its range for the first time, having been previously accustomed only to the fowling-piece, and kept just outside the two thousand yards' range, or whatever range it was, retaining their composure perfectly at that distance. We suppose the wonderful accuracy of the travelling birds in striking the exact point for which they are bound, of which Mr. Leith Adams gives us wonderful illustra- tions, is a still greater proof of the same power. Mr. Adams tells us of swifts which, after eight months' absence in the South,—at a distance of some 1,800 or 1,900 miles,—return not merely to the same region, but to the same nests which they had deserted, and that, too, year after year,—the individuals having been marked so that there could be no mistake as to their identity, unless indeed there be such creatures as Claimants to abandoned nests even in the ornithological world. Again, the delicate adaptation of the power of geometrical measurement to the welfare of its species seems to be shown by the weaver-bird of India, which hangs its "elaborately constructed, purse-shaped nest" "from the tops of branches over- hanging deep wells," in order to render it particularly difficult for enemies to get at the nest without running a great risk of falling into the well.
Again, none of the lower animals, except the monkey, seems to have so much imitative power, particularly in relation to sounds, —the imitative power of monkeys has more of capacity in it for imitating gestures,—as parrots, mocking-birds, ravens, and other tribes of birds. Curiously enough, this seems to be more or less a quality of tame, as distinguished from wild birds. At least, Mr. Leith Adams says that parrots, the cleverest of all these imitators when in captivity, "are not by any means given to copy the call-notes of other birds in their native woods," so that imitation would seem to be the channel into which their intellectual energy is apt to be directed, when they are robbed of their natural occupations. That is, we suppose, their perceptions being very acute, and their voice well developed, directly they are cut off from their usual occupations, they begin to imitate all they hear by way of exercising their latent faculties. That birds can go beyond mere imitation, and are to some extent accomplished actors, the evidence as to all those birds which, by false pretences of agitation, lure the trapper away from the vicinity of their nest, completely shows. Mr. Leith Adams bears witness to this, and tells besides the story of the trick played by the ruby-throated hum- ming-bird of Canada, which, if captured, "feigns death by shutting its eyes and remaining quite motionless," and then sud- denly makes a vigorous effort to escape. This shows not merely a dramatic gift, but a distinct purpose in the use of it. Ruses of a similar kind are, however, not unexampled in other animals than birds. Cats, for instance, coast mtly feign sleep, for the purpose of catching birds or mice more effectually.
On the whole, however, it may be safely said that birds seem to have much more capacity for perceiving beauty, much more gift for social enjoyment, a finer knowledge of distance and direction, and more power of vocal imitation, than any other order of animals of which we know anything. On the other hand, they have less sense of power and sympathy than the dog, and there- fore, much less sense of responsibility to their superiors, whom they often love, but seldom serve. Perhaps we might generalise these mental qualifications by saying that birds are chiefly educated by perceptions, wonderfully accurate indeed, but still of things at a distance, of things at an almost telescopic range ; that their rapidity of flight makes them creatures of wide experience, but not of full experience of any species but their own ; and that as a result, they cannot know men well enough to learn as much from men, as dogs, and cats, and elephants, and even other orders of creatures learn. Birds, in short, get bird's-eye views of the earth, and bird's-eye views, however instructive to those who have previously mastered the details carefully, do not exactly furnish a good basis for progressive knowledge. They obviously get a knowledge of geography, and in some sense of the air and its currents, such as no other creatures can have. They have an ear for music and an eye for harmony of form and colour, and probably of movement,—for there are bird-dances which Taglioni would have despaired of imitating,—such as no other member of the animal world possesses ; and the perception of beauty, we know, depends on nothing so much as the coup and this birds can always command. But they lose, by their great privi- lege of wings, that slow and sure experience of the ways of man which some less gifted animals acquire. A swift which flies at the rate of 270 miles an hour, according to Mr.
Leith Adams, clearly cannot have a brain to utilise an ex- perience acquired at that rate in any but a very perfunc- tory way. Therefore, though birds have so strange a percep- tion of beauty, which hardly needs close analysis, they are too fast, too migratory in their habits, to learn anything which needs perfect fidelity and vigilance confined to a very narrow circle of facts. They are the musicians, and we might almost say the sensu- ous poets of the animal world, but musicians and sensuous poets do not conduce to progressive knowledge and ethical culture. Birds range too high and fly too fast for sympathy with man, and so it happens that their intellectual powers, remarkable and unique as they are in the animal world, never become so human and so almost spiritual as those of creatures which can only boast of very inferior powers.