These ants winnow or husk the grain after it has been carried into the nest. All during the harvesting I observed workers bringing chaff from the nest and carrying it some distance away. It is said by Texan observers that the harvesters of that state bring the grain to the surface and dry it, if, perchance, it becomes wet. I have never observed this myself, but accept it as an established fact.[84]
[84] I believe that these observations on the presence of the harvester ant in Arkansas are unique; at least I have been unable to find any data corroborative of this fact. How did a fecundated queen arrive at a spot so far from her usual habitat?--W.
The faculty of computing is among the very last of the psychical habitudes acquired by man, and is an evidence of high ratiocinative ability. Many of the savage races are unable to count above three,--some not above five,--thus demonstrating the truthfulness of the above a.s.sertion. Yet I believe that it can be clearly shown that some of the lower animals and many of the higher animals are able to count.
The mason wasps, or mud-daubers, build their compartment houses generally in places easily accessible to the investigator; therefore the experiments and observations which I am about to detail can be duplicated and verified without difficulty. These interesting members of the Hymenoptera, the _avant-couriers_ of the social insects, can be seen any bright day in August or September busily engaged on the margins of ponds, ditches, and puddles in the procurement of building materials. They will alight close to the water"s edge, and, vibrating their wings rapidly, will run hither and thither over the moist clay until they arrive at a spot which, in their opinion, will furnish suitable mortar. Quickly biting up a pellet of mud, they moisten it with saliva, all the while kneading it and rolling it between maxillae and palpi. When it has reached the proper consistency they bear it away to some dry, warm place, such as the rafters of an outhouse or a garret, and there use it in the construction of their adobe or mud nests.
There may be dozens of these nests in the process of construction, and arranged on the rafters, side by side, yet these busy little masons never make the mistake of confounding the houses; after securing mortar they invariably return, each to her own structure. This statement can be easily verified. While the insect is engaged in applying the mortar, take a camel"s-hair brush and quickly paint a small spot on her shoulders with a mixture of zinc oxide and gum arabic; then mark the nest. The marked wasp will always return to the marked nest.
As soon as the cells are completed, the wasp deposits an egg in each, and immediately begins to busy herself about the future welfare of the coming baby wasps. Just here these remarkable creatures show that they possess a mental faculty which far transcends any like act of human intelligence; they are able to tell which of the eggs will produce males and which females. Not only are they able to do this, but, seemingly fully aware of the fact that it takes a longer time for the female larvae to pupate than it does the male larvae, they provide for this emergency by depositing in the cells containing female eggs a larger amount of food. It is in the procurement and storage of this food-supply that these insects give unmistakable evidence of the possession by them of the faculty of computing.
The knowing little mother is well aware of the fact that as soon as the egg hatches the young grub will need food, and an abundance of food at that; so, before closing the orifice of the cell, she packs away in it the favorite food of her offspring, which is spiders. She knows that in the close, hot cell the spiders, if dead, would soon become putrid and unfit for food: therefore, she does not kill them outright, but simply anaesthetizes them by instilling a small amount of poison through that sharp and efficacious hypodermic needle, her sting.[85]
[85] As a matter of fact I have kept Argiope under observation in this anaesthetized condition for _thirteen weeks_.--W.
Each variety of masons uses a different spider; the common blue mason is partial to the beautiful Argiope, which, banded as it is with gray and yellow, is a very conspicuous object when seen on its glistening, upright web.
The wasp larva, as soon as it emerges from the egg-membrane, finds fresh and palatable food before its very nose, and at once begins to eat.
In the case of the male larvae, five spiders are deposited in each cell, while eight are always placed in the female compartments.[86] If one or more spiders are removed from the cell, the mother wasp does not appear to notice that her food-supply has been tampered with; she completes her quota, five for the males and eight for the females, and then closes the cell, no matter if there remains in the compartment one, two, or three spiders. Her count calls for five or eight, as the case may be, and, when she has put on top of the egg the requisite number according to her count, her responsibility ceases.
[86] Compare Kirby and Spence, _Entomology_, pp. 231, 232, habits of _Epipone spinipes_ in regard to small grubs.
I have never known a mud-dauber to make a mistake in her computation, although I have endeavored to puzzle this little arithmetician time and again. If a wad of paper be placed in a cell after two or three spiders have been deposited, thus partially filling it, the insect knows at once that something is wrong, and will proceed to investigate. She will remove the spiders on top of the paper, will extract the wad, and will then proceed with her count. On the other hand, if several spiders be taken out when the count calls for only one or two more, the wasp does not appear to notice that the cell is almost empty; she finishes her count as if everything were correct, and then seals up the opening with mud.
The quail lays some twelve or fifteen eggs, and seems to be aware of the fact that some of her eggs are missing when several have been removed from the nest. When one of these birds has laid six or eight eggs, if two or three be removed she will abandon the nest and deposit the remainder of her eggs elsewhere. This behavior on the part of the bird has been attributed to her sense of smell; she, detecting the presence of an enemy by the scent of his hand left behind in the nest, recognizes the danger, and therefore abandons the nest. But numerous experiments along this line teach me that smell has nothing to do with it whatever.
I have removed eggs with a long iron ladle, the bowl of which I had carefully refrained from touching, and also with sticks freshly cut in the wood, and yet the birds would invariably abandon their nests. On the contrary, when all, or nearly all, the eggs have been laid, several may be removed either with the ladle or with the naked hand, and yet the bird will not abandon her nest. She seems to be able to count up to six or eight; beyond this latter number her faculty of computing does not extend. After the full laying has been deposited in the nest and the process of incubation has become established, a large number of the eggs may be removed, and yet the bird will continue to set until the remaining eggs have been hatched out.
The faculty of computing seems to be present in other birds to some extent; the domesticated guinea-fowl and the turkey sometimes possess it in a marked degree, though in most of these fowls domestication has almost entirely eradicated it. The domestic barnyard hen has had her nest robbed for such a long period of time that she has lost the faculty of counting. But even this meek provider of food for mankind is able, in some instances, to count one: she will not lay in her nest unless a nest-egg be left to delude her. The nest-egg may be wholly fact.i.tious and made of china, marble, chalk, stone or iron painted white; the hen does not seem to care so long as it bears some resemblance to an egg.
That the turkey-hen can count, the following instance occurring under my own observation would seem to indicate. The bird had a nest in my garden in which she had deposited three eggs. One day another turkey, seized with a desire of ovipositing, spied this nest and laid an egg therein. The original owner of the nest came along soon after the interloper had left her egg; she examined the nest carefully, and turned the eggs with her beak. Finally she thrust her beak through the sh.e.l.l of an egg and bore it far from the nest before dropping it on the ground.
Now, as far as I could tell, the eggs were alike, but the sharper and more discriminating eyes of the turkey undoubtedly saw, on close examination, some peculiarity in color or shape in the stranger"s egg, and therefore bore it away and destroyed it. I believe, however, that her attention was arrested at first by the unexpected number of eggs in the nest, and that she was enabled to detect the stranger"s egg only after much inspection and comparison.
Many animals have been taught to count, but none of them show that they fully appreciate the value of numerical rotation. Of course, in the vast majority of trained animals, the seeming appreciation is only a trick founded on the sense of smell, sight, touch, or taste.
An instance recently came under my personal observation in which a dog, a high-bred collie, seemingly evinced an abstract idea of numbers. The animal in question received an injury a year or so ago through which she became permanently and totally blind. Recently she gave birth to a litter of six puppies, all of which were uniform in size and markings.
Immediately after the birth of the puppies, the dog"s owner had mother and young removed from the dark cellar in which they then were, and carried to a warm and well-ventilated room in his stables.
In the darkness of the cellar one of the puppies was overlooked and left behind. As soon as the mother entered the box in which her young had been placed, she proceeded to examine them, nosing them about and licking them. Suddenly she appeared to become very much disturbed about something; she jumped out of the box and then jumped back again, nosing the puppies as before. Again she jumped from the box and then made her way toward the cellar, followed by her astonished owner, who had begun to have an inkling as to what disturbed her. She had counted her young ones, and had discovered that one had been left behind. Sure enough, the abandoned puppy was soon found and carried in triumph to the new home.
So astonished was the gentleman[87] at this blind creature"s intelligence that he resolved to experiment further; he removed another puppy and walked away with it in his arms. It was not long before the blind mother showed her distress so plainly, that I begged him to return the puppy, which, having been returned to her, she caressed for a moment or so, and then gave herself up to the chief function of maternity, suckling her young.
[87] Karl Becker, Esq., St. Louis, Mo.
It is beyond reason to suppose that this dog discovered the absence of her young one through her sense of smell. Granted that to the maternal nose each puppy had an individual and particular odor (which I do not believe), it is hardly possible, nay, it is impossible, that the dog"s sensorium had recognized and retained these different scents in the short time which had elapsed since their birth. It is much more reasonable to suppose that the dog knew that she had given birth to six young ones, and that she had counted them when they had been removed to their new home. Again, it is a well-known fact that a dog can retain only one scent at a time; hence, this fact alone would militate somewhat against the idea that the sense of smell was the detecting agent in this case. Nor could it have been the sense of touch; the mother could not have possibly familiarized herself with the individual form of each puppy in so short s.p.a.ce of time. It is folly to suppose that each young one had a distinctive taste or flavor; hence the sense of taste must also be eliminated. Thus, by exclusion, there remains but one faculty, the faculty of computing, to account for the dog"s actions.
Several years ago there lived in Cincinnati a mule which was employed by a street railway company in hauling cars up a steep incline. This animal was. .h.i.tched in front of the regular team, and unhitched as soon as the car arrived at the top of the hill. It made a certain number of trips in the forenoon (I have forgotten the number, but will say fifty for the sake of convenience), and a like number in the afternoon, resting for an hour at noon. As soon as the mule completed its fiftieth trip, it marched away to its stable without orders from its driver. To show that it was not influenced by the sound of factory whistles and bells, the following remarkable action on the part of this animal is vouched for by the superintendent of the line, who gave me these data.
On a certain occasion, during a musical festival, this mule was transferred to the night shift, and the very instant it completed its fiftieth trip it started for the stables. It took the combined efforts of several men to make it return to its duty. At night there were no bells or whistles to inform the creature that "quitting-time" had come; it thought the time for rest and food had arrived as soon as it had completed its fifty trips.[88]
[88] These data were given to me at a certain club banquet where I had no facilities for noting them down. I have endeavored to locate the superintendent in question, but without success; I believe, however, that he gave the facts just as they occurred.--W.
My meals are always served at regular appointed hours, which never vary throughout the year; and, since my cook "prides herself" on her punctuality, they are always served on the stroke of the clock. The moment the bell rings, my cat, a large and very intelligent male, takes up a position at the door, and is generally the first to enter the dining room. A few moments before meal-time, Melchizedek (for he is of royal blood and bears a royal name) becomes uneasy, jumping from chair to floor or from floor to chair, and sometimes mewing gently. The moment the bell rings, he is all animation, and shows by his actions that he fully understands its meaning. He never mistakes the sound of the dressing-bell for that of the tea-bell, though the same bell is used.
This cat may not be able to count, but that he notes the pa.s.sage of time I do not for an instant doubt.
Some monkeys give unmistakable evidences of the possession by them of the computing faculty. In 1889 I made the acquaintance of a very intelligent chimpanzee which could count as high as three. That this was not a trick suggested by sensual impulses I had ample opportunity of satisfying myself. The owner of the animal would leave the room, no one being present but myself, and when I would call for two marbles, or one marble, or three marbles, as the case might be, the monkey would gravely hand over the required number. Romanes mentions an ape that could count three, the material used in his experiment being straws from the animal"s cage.
The fact that monkeys can count does not appear so remarkable when it is agreed by the best authorities that they are capable of understanding human speech.[89]
[89] Romanes, _Mental Evolution in Man_, p. 369; Darwin, _Descent of Man_, p. 87; Whitney, _Enc. Brit._, "Philology," Vol. XVIII. p. 769, quoted by Romanes, _super_.
Returning for a moment to insects, we find that bees and ants give many evidences of intelligent correlative ideation and action for definite purposes not instinctive. In regard to bees, Huber"s experiment with the gla.s.s slip proves conclusively, in my opinion, that these creatures _reason_. This experiment is so interesting that it will bear recital.
Huber placed a slip of gla.s.s in front of a comb that was under construction. The bees, as if perfectly aware of the fact that it would be difficult to affix the comb to the slippery surface of the gla.s.s, curved it at a right angle around the slip of gla.s.s and fastened it to the wooden wall of the hive![90]
[90] Huber, Vol. II. p. 230; quoted also by Kirby and Spence, _loc.
cit. ante_, p. 582.
It is folly to suppose that bees have an instinctive knowledge of gla.s.s, hence we are forced to conclude that they were governed in this instance solely by reason.
Furthermore, as the inner surface of the comb was concave, and the outer surface convex, the bees made the cells on the former much smaller, and those on the latter much larger, than usual!
"How, as Huber asks, can we comprehend the mode in which such a crowd of laborers, occupied at the same time on the edge of the comb, could agree to give it the same curvature from one extremity to the other; or how could they arrange together to construct on one face cells so small, while on the other they imparted to them such enlarged dimensions?"[91]
[91] Kirby and Spence, _loc. cit. ante_, pp. 582, 583.
Surely, no "variation of instinct," however complex, can possibly account for such a deviation from the normal!
It is hardly necessary to give more evidence as to the presence of reason in the psychical organisms of the lower animals; I believe that I have clearly demonstrated that some of them do make use of intelligent ratiocination. To prove that this view, _i.e._ that the lower animals reason, is widely held, I need only point to the works of such men as Darwin, Buchner, Forel, Huber, Lubbock, Hartmann, Kirby and Spence, and dozens of others.[92]
[92] Darwin, _Descent of Man_; Romanes, _Animal Intelligence_, _Mental Evolution in Animals_, _Mental Evolution in Man_; Lubbock, _Senses, Instincts, and Intelligence of Animals_, and _Ants, Bees, and Wasps_; Hartmann, _Anthropoid Apes_; Buchner, _Geistesleben der Thiere_; Huber, _Natural History of Ants_, etc.
We have seen that the lower animals seem to possess very near, if not quite, all of the _fundamental_ psychical habitudes of the highest animal of all--_h.o.m.o sapiens_; we will now proceed to study certain psychical attributes in the possession of the lower animals which man has lost in the process of evolution. These attributes will be embraced under the heading of Auxiliary Senses.
CHAPTER VIII
AUXILIARY SENSES
When we come to examine the methods by which, or through which, many of the lower animals protect themselves from their enemies, we soon discover that some of these means are very wonderful indeed. It is not my purpose to discuss instinctive protective habits in this chapter; I wish rather to call attention to two _senses_,[93] which are to be observed in certain of the lower animals, and which man and some of the higher animals have lost in the process of evolution. I refer to tinctumutation, the "color-changing" sense, and the sense of direction, or, as it is commonly and erroneously termed, the "homing instinct."
Neither of these faculties is instinctive, but they are, on the contrary, true senses, just as hearing, or taste, or smell is a sense.
Careful dissections and repeated experiments have shown me, beyond peradventure, that these two psychical habitudes have their centres in the brains (ganglia) of animals which possess them.
[93] I believe that I am the first to claim the _sensual_ importance of tinctumutation and the sense of direction or the "homing sense."
Heretofore they have been regarded, by all authorities as far as I know, as instinctive in character.--W.