Part 14
Of course it is open to any one to assert that, in this case, the crow that discovers the food does not consciously call its companions; at the sight of its food it instinctively caws, and its companions obey the caw instinctively, without knowing why they do so. No one, however, who watches crows for long can help believing that they think. The fact that they hang about the kitchen every day at the time the cook pitches out the leavings seems inconsistent with the theory that birds cannot think. The crows obtained food at this place yesterday and the day before at a certain hour, and the fact that they are all on the look out for food to-day shows, not only that they possess a good memory, but that they are endowed with a certain amount of reasoning power.
Many animals have very good memories. Now, in order that an animal may remember a thing it must think. Its thoughts are of course not clothed in language as human thoughts are, but they nevertheless exist as mental pictures.
According to Professor Thorndike, the psychic life of an animal is “most like what we feel when our consciousness contains little thought about anything, when we feel the sense impressions in their first intention, so to speak, when we feel our own body and the impulses we give to it (or that outward objects give to it). Sometimes one gets this animal consciousness; while in swimming, for example. One feels the water, the sky, the birds above, but with no thoughts about them, or memories of how they looked at other times, or æsthetic judgments about their beauty. One feels no ‘ideas’ about what movements he will make, but feels himself make them, feels his body throughout. Self-consciousness dies away. The meanings and values and connections of things die away. One feels sense-impressions, has impulses, feels the movements he makes; that is all.”
This is probably a good description of the state of mind of a dog when he is basking in the sunlight; he is thinking of nothing. But he hears the shrill cry of a squirrel—this at once recalls to him the image of the little rodent and past _shikar_. In a moment the dog is on the alert; he is now thinking of the squirrel, and his instinct and inclinations teach him to give chase to it. Or he hears a footstep; he recognises it as that of his master, sees that the latter is wearing a _topi_, and at once pictures up a run in the compound with his master. But his owner chains him up. The dog looks wistfully at his master’s retreating figure and pulls at his chain; it is surely absurd to say that the dog is not thinking. The picture of a scamper beside his master rises up before him, and he feels sad because he knows that the scamper is not likely to become a _fait accompli_.
Again, you have been accustomed to throw a stick for your dog to run after and carry back to you. You are out walking accompanied by your dog; he espies a stick lying on the ground; at once images of previous enjoyable runs after the stick rise up in his mind; he picks up the stick and brings it to you, drops it at your feet and looks up at you. You pretend to take no notice. The dog then picks up the stick and rubs it against your legs. To believe that the dog while acting thus does not think, that he is merely obeying an inborn instinct, is surely a misinterpretation of facts. Animals have but limited reasoning powers, and their thoughts are not our thoughts, they are not clothed in language, they are merely mental pictures, called up either subjectively, as when a dog barks while dreaming, or objectively by some sight or scent, but nevertheless such sensations are thoughts.
While maintaining that the higher animals can and do think, I am ready to admit that a great many of their actions which are apparently guided by reason are in reality purely instinctive. Thus the building of a nest by a bird must, at any rate on the first occasion, be a purely instinctive action. The creature cannot know what it is doing. Nor can it have any thoughts on the matter; it suddenly becomes an automaton, a machine, acting thoughtlessly and instinctively.
Some internal force which is irresistible compels it to seek twigs and weave them into a nest. The bird has no time to stop and think what it is doing, nor does it wish to, for it enjoys nest building. It is, of course, impossible for a human being to understand the frame of mind of a bird when building its first nest. The only approach to it that we ever experience is when we are suddenly seized with an impulse to do something unusual, and we obey the impulse and are afterwards surprised at ourselves.
There is a story told of a wealthy man who had been out hunting and was returning home tired and thirsty. He dismounted at a farm-house, went inside and asked for a drink. While this was being obtained he noticed a lot of valuable old china on the dresser: seized by a sudden impulse, he knocked it all down, piece by piece, with his riding whip. His hostess on her return with the drink looked surprised. The hunting man smiled, asked her to name the value she set on the china, sat down and, there and then, wrote out a cheque for the amount.
It always seems to me that when a bird begins for the first time to collect materials for a nest she must act impulsively, without thinking what she is doing. Just as the hunting man was seized with a sudden desire to smash the crockery with his whip, so is she suddenly impelled to collect twigs and build a nest.
Another instinctive act which is apparently purposeful is the feigning of injury by a parent bird when an enemy approaches its young. Superficial observation of this action leads the observer to imagine that the mother bird behaves thus with deliberate intent to deceive, that in so doing she consciously endeavours to distract attention while her young ones are betaking themselves to cover. As a matter of fact, the bird will behave in precisely the same way if she have eggs instead of young ones. This has, of course, the effect of drawing attention to the eggs, and proves that the action is instinctive and not the result of reasoning.
Most people have remarked the cautious manner in which many birds approach the nest when they are aware that they are being watched. This has the appearance of a highly intelligent act. It is, however, nothing of the kind.
I have taken young birds from a nest, handled them and replaced them in full view of their frantic parents. Then I have retired a short distance and watched the parents. These invariably display the same caution in approaching the nest as they did before I had discovered its whereabouts.
Birds and beasts think much less than they are popularly supposed to do. It is absurd to attribute to them reasoning powers similar to those enjoyed by man; it is equally absurd to assert that they do not think at all.
A COUPLE OF NEGLECTED CRAFTSMEN
Two Indian birds have a world-wide reputation. Every one has heard of the weaver bird (_Ploceus baya_) and the tailor-bird (_Orthotomus sutorius_). Their wonderful nests are depicted in every popular treatise on ornithology. They are both master-craftsmen and deserve their reputation. But there are in India birds who build similar nests whose very names are unknown to the great majority of Anglo-Indians. The Indian wren-warbler (_Prinia inornata_) weaves a nest quite as skilfully as the famous weaver bird. This neglected craftsman is common in nearly all parts of India, and, if you speak of the weaver bird to domiciled Europeans, they will think you mean this wren-warbler, for among such he is universally called the weaver bird; the famous weaver, whose portrait appears in every popular bird book, is known to them as the baya.
As its name implies, _Prinia inornata_ is a plainly attired little bird. Its upper parts are earthy brown. It has the faintest suspicion of a white eyebrow, and its under plumage is yellowish white, the thighs being darker than the abdomen. Picture a slenderly built wren with a tail three inches in length, which looks as though it were about to fall out and which is constantly being waggled, and you have a fair idea of the appearance of this little weaver. But this description applies to dozens of other birds found in India. The various warblers are so similar to one another in appearance as to drive ornithologists to despair. The inimitable “Eha” admits that they baffle him. “There is nothing about them,” he writes, “to catch the imagination of the historian, and they will never be famous. I have been perplexed as to how to deal with them. . . . To attempt to describe each species is out of the question, for there are many, and they are mostly so like each other that even the title ornithologist does not qualify one to distinguish them with certainty at a distance. If you can distinguish them with certainty when you have them in your hand you will fully deserve the title.”
It is, however, possible to recognise the Indian wren-warbler by its note. When once you have learned this you are able to identify the bird directly it opens its mouth. But how shall I describe it? It is a peculiar, harsh but plaintive, _twee, twee, twee_; each _twee_ follows close upon the preceding one, and gives you the idea that the bird is both excited and worried. If you see a fussy little bird constantly flitting about in a cornfield and uttering this note, you may be tolerably certain that the bird is the Indian wren-warbler. It never rises high in the air; it is but an indifferent exponent of the art of flying. It moves by means of laborious jerks of its wings. It is a true friend to the husbandman, since it feeds exclusively on insects. The most remarkable thing about it is its nest. This is a beautifully woven structure, composed exclusively of grass or strips of leaves of monocotyledonous plants which the bird tears off with its bill. These strands are invariably very narrow, and are sometimes less than one-twentieth of an inch in breadth. The nest may be described as an egg-shaped purse, some five or six inches in depth and three in width, with an entrance at one side, near the top. It is devoid of any lining, and its texture puts one in mind of a loosely made loofah. The nest is sometimes attached to two or more stalks of corn, or more commonly it is found among the long grasses which are so abundant in India. When the nest is built in a cornfield the birds have to bring up their family against time. They are unable to begin nest-building until the corn is fairly high, and must, if the young are to be safely started in life, have brought them to the stage when they are able to leave the nest by the time the crop is cut.
In India nearly every field of ripe corn has its family of wren-warblers; the two parents flit about, followed by a struggling family of four. These little birds do not by any means always defeat time. Numbers of their nests containing half-fledged young are mown down at every harvest by the reaper’s sickle. The nest is woven in a manner similar to that adopted by the baya; the cock and hen in each case work in combination. Its texture is looser than that of the more famous weaver, but it is not less neatly put together. In it are deposited four or five pretty little green eggs, marked with brown blotches and wavy lines.
Our second neglected craftsman is a tailor. It sews a nest so like that of the world-famous tailor as to be almost indistinguishable from it. Some authorities declare that the two nests are distinguishable. They assert that the nest of _Orthotomus_ is invariably lined with some soft substance, such as cotton-wool, the silky down of the cotton tree, soft horse-hair, or even human hair, while that of the species of which we are speaking is lined with grass or roots. This distinction does not, however, invariably hold. I have seen nests of this species which have been lined with cotton-wool.
This bird is known to ornithologists as the ashy wren-warbler (_Prinia socialis_). Anglo-Indian boys call it the tom-tit. It is a dark ashy-grey bird, with the sides of the head and neck and the whole of the lower plumage buff. There is a tinge of rufous in the wings and tail. It is most easily distinguished by the loud snapping noise it makes during flight. How this noise is produced we do not know for certain. Reid was of opinion that the bird snapped its long tail. What exactly this means I do not know. Jesse believes that the sound is produced by the bird’s mandibles. I have spent much time in watching the bird, and am inclined to think that the noise is caused by the beating of the wings against the tail. This last is constantly being wagged and jerked, and it seems to me that the wings beat against it as the bird flits about. When doves and pigeons fly, their wings frequently meet, causing a flapping sound. I am of opinion that something similar occurs when the ashy wren-warbler takes to its wings.
Perhaps the most extraordinary thing about this bird is the well-authenticated fact that it builds two types of nest. Besides this tailor-made nest, the species makes one of grass, beautifully and closely woven, domed, and with the entrance near the top. I have never seen this latter type of nest, but so many ornithologists have that there can be no doubt of its existence.
The strange thing is that both types of nest have been found in the same neighbourhood, so that the difference in the form of nursery is not a local peculiarity.
I am at a loss to account for the existence of these two types of nest. I have no idea how the habit can have arisen, nor do I know what, if any, benefit the species derives from this peculiarity. So far as I am aware, no one can say what it is that leads to the construction of one type of nest in preference to the other. The nests of this species present a most interesting ornithological problem. I hope one day to be in a position to throw some light on it; meanwhile I shall welcome the news that some one has forestalled me. The ashy wren-warbler is a common bird, so that most Anglo-Indians have a chance of investigating the mystery. The same kind of eggs are found in each type of nest. They are of exceptional beauty, being a deep mahogany or brick-red, so highly polished as to look as though they have been varnished.
BIRDS IN THEIR NESTS
Just as every Englishman is of opinion that his house is his castle, so does every little bird resent all attempts at prying into its private affairs in the nest. For this reason we really know very little of the home-life of birds. It is not that there are no seekers after such knowledge. Practical ornithology is a science that can boast of a very large number of devotees.
Many men spend the greater part of their life in endeavouring to wrest from birds some of their secrets, and such must admit that the results they obtain are as a rule totally disproportionate to the magnitude of the efforts. At present we know only the vague generalities of bird life.
We know that the hen lays eggs; that she, with or without the help of the cock, as the case may be, incubates these eggs; that the young, which are at first naked, are fed and brooded until they are ready to leave the nest, when they are coaxed forth by the parents, who hold out tempting morsels of food to them. But these are mere generalities. Our ignorance of details is very great.
The nests of most passerine birds are scrupulously clean. Young birds have enormous appetites, and much of the food which they eat is indigestible and must pass out as droppings, yet in the case of many species no sign of these droppings is visible, either in the nest, or on the leaves, branches, or the ground near the nest. What becomes of these droppings? Ornithological treatises are silent upon this subject.
Again, young birds are born naked, and in India are frequently exposed to very high temperatures, so that much liquid must pass from their bodies by evaporation. How is this liquid made good? Do the parents water the birds, if so, how? I have never seen any mention of this in an ornithological treatise.
Let us to-day consider these two subjects: the sanitation of the nest and the method of assuaging the thirst of young nestlings.
As regards the first we have some knowledge, thanks to the patient labours of Mr. F. H. Herrick, an American naturalist, whose book, _The Home Life of Birds_, I commend to every lover of the feathered folk. Unfortunately, Mr. Herrick’s book is to some extent spoiled for Englishmen, because it deals with birds with which they are unfamiliar; nevertheless, its general results apply to all passerine birds.
Mr. Herrick is a very keen bird photographer. As every one knows, he who wishes to obtain good photographs of birds has two great difficulties to overcome. The first is to get near to his subjects, and the second is to find them and their nests in situations suitable for photography.
The former is usually overcome by the photographer concealing himself and his camera in a tent or other structure. At first the birds are afraid of the concealing object, but soon maternal affection overcomes their fear.
Mr. Herrick’s method of overcoming the second of these two difficulties is to remove the nest to be photographed from the concealed situation in which it is usually built, and place it in a more open place. If the nest be thus moved when the young are some seven or eight days old, the parents will almost invariably continue to feed their young in the new situation, for at that particular period the parental instinct is at its zenith. In addition to obtaining a splendid series of photographs, Mr. Herrick has observed, from a distance of a few inches, the nesting habits of several American birds. As the result of these observations he is able to declare that nest-cleaning follows each feeding with clock-like regularity. “The excreta of the young,” he writes, “leave the cloaca in the form of white opaque or transparent mucous sacs. The sac is probably secreted at the lower end of the alimentary canal, and is sufficiently consistent to admit of being picked up without soiling bill or fingers. The parent birds often leave the nest hurriedly bearing one of these small white packages in bill, an action full of significance to every member of the family. . . . Removing the excreta piecemeal and dropping it at a safe distance is the common instinctive method, not only of insuring the sanitary condition of the nest itself, but, what is even more important, of keeping the grass and leaves below free from any sign which might betray them to an enemy.” These packets of excrement are quite odourless, and they are often devoured by the parent bird instead of being carried away. The digestion of very young birds must be feeble, and doubtless much of the food given them passes undigested through the alimentary canal, so that it is capable of affording nourishment to the parents. Birds are nothing if not economical.
Of course, all birds are not so careful of the sanitation of the nest. Every one knows what a filthy spectacle a heronry is. According to Mr. Herrick, the instinct of inspecting and cleaning the nest is mainly confined to the great passerine and picarian orders. It is obviously not necessary in the case of those birds, such as fowls, of which the young are able to run about when born; nor is it needful in the case of birds of prey, who take no pains to conceal the whereabouts of the nest. Young raptores eject their semi-fluid excreta over the edge of the nursery; thus the nest is kept clean, but the droppings on the ground betray its presence to all the world.
Coming now to our other question: How do young birds obtain the water which they require? we have no help from Mr. Herrick. He makes no mention of this in his most interesting book. It is possible that nestlings are not given anything to drink, that the juicy, succulent insects or fruits with which they are supplied contain sufficient moisture for their requirements. We must remember that the skin of birds is very different from that of man. It contains no sweat glands, so that a bird, like a dog, can only perspire through its mouth.
The breath of mammals is so surcharged with moisture that when it is suddenly cooled the water vapour in it condenses; the result is we can “see the breath” of a mammal on a cold day. I have never succeeded in seeing a bird’s breath, so am of opinion that the fowls of the air do not exhale so much moisture as mammals do. But even allowing for this, a considerable amount of moisture must be given out in expiration, so that it seems probable that young birds require more moisture than they obtain in their food. Drops of water have to be administered to hand-reared birds. Many birds fill up the crop with food and then discharge the contents into the gaping mouths of their young. In this condition the food must be mixed with a considerable quantity of saliva and possibly with water. The crop of a bird is a receptacle into which the food passes and remains until actually utilised. There seems no reason why water should not be stored for a short time in this receptacle just as food is. Perhaps birds “bring up” water as they do solid food, and thus assuage the thirst of their young. Such a process would be very difficult to detect; it would be indistinguishable from ordinary feeding to the casual observer. I hope that some physiologist will take up the matter. A quantitative analysis of the air exhaled by a bird should not be very difficult to make.
BULBULS
More than fifty species of bulbul are found in India—bulbuls of all sorts and conditions, of all shapes and sizes, from the brilliant green bulbuls (which, by the way, strictly speaking, are not bulbuls at all) to the dull-plumaged but blithe white-browed member of the community, so common in Madras; from the rowdy black bulbuls of the Himalayas to the highly respectable and well-behaved red-vented bulbuls. He who would write of them is thus confronted with an _embarras de richesses_. The problem that he has to solve is, which of the many species to take as his theme.
The polity of birds is said to be a republic. The problem may, therefore, well be elucidated on democratic principles. The first and foremost of these—the main plank of every demagogue’s platform—is, of course, “one bulbul, one vote.” The second is like unto the first, “every bulbul for itself.” Therefore, on being asked to elect a representative to be the subject-matter of this paper, each will vote for his own species, and the result of the poll will be: Bulbuls of the genus _Molpastes_ first, those of the genus _Otocompsa_ a good second, and the rest a long way behind. Let us then conform to the will of the majority and consider for a little these two species of bulbul, which resemble one another very closely in their habits.
_Molpastes_ is a bird about half as big again as the sparrow, but with a longer tail. The whole head is black and marked by a short crest. There is a conspicuous crimson patch of feathers under the tail. The remainder of the plumage is brown, but each feather on the body is margined with creamy white, so that the bird is marked by a pattern that is, as “Eha” points out, not unlike the scales on a fish. Both ends of the tail feathers are whitish.
_Otocompsa_ is a more showy bird. The crest is long and projects forward over the forehead. The crimson patch, so characteristic of bulbuls, also exists in this species. There is a similar patch on each side of the head—whence the bird’s name, the red-whiskered bulbul. There is also a white patch on each cheek. The white throat is separated from the whitish abdomen by a conspicuous dark brown necklace. This bird must be familiar to every one who has visited Coonoor or any other southern hill station. The less showy variety—the red-vented bulbul, as it is called—is common in and about Madras.