The Dawn of Reason; or, Mental Traits in the Lower Animals

by Jr. James Weir

Instinct is the bugbear of psychology and does more to retard investigation than any other factor. As long as people of the creationist stamp wield the instinct-club, just so long will they be unable to grasp the idea of intelligent ratiocination in the lower animals. A company of men rebuilding a wall which has been overthrown by a tempest are said to be governed and directed by reason, while a company of ants doing precisely the same thing, and with just as much intelligence, are said to be directed by instinct![83]

In the neighborhood of Hell's-Half-Acre, a desolate and rocky valley a short distance from Hot Springs, Arkansas, in 1887, I discovered several communities of harvester ants, and closely and carefully observed their habits. The first time I noticed them was early in the spring, when they seemed to be engaged in planting their grain. They were bringing out the little grass-seeds by the hundreds and thousands, and carrying them some distance from the nest, where they were dropped on the turf. It is possible that these ants were only getting rid of spoiled grain, but I think not, for several of the seeds secured and planted by me germinated. I observed them again in about a month, and the grass was growing finely on the plat where they had deposited the seeds. Not a single stalk of any other kind of grass and not a single weed were to be seen in this model grain-field. The ants had evidently removed every plant that might interfere with the growth of their grain.

I saw them again in August when they were reaping the crop and storing the grain away in their nests. The ants would climb the grass-stems until they came to the seeds; these they would then seize in their mandibles, outer sheath and all, and, by vigorously twisting them from side to side, would separate them from the stalk; they would then crawl down and carry them into the nest. I did not notice here the roads and pathways so generally found leading to the nests of the Texas variety of the harvester. Around the nests the surface of the ground was smooth and bare, but there were no highways or roads leading to them.

Among the workers I saw some ants whose heads and mandibles were very large. These ants never engaged in any of the agricultural pursuits of their sisters; they were the soldiers and the sentinels of the community. One nest migrated while I had them under observation, and I had the pleasure of witnessing the behavior of these fearless little warriors when on the march. The ants were moving nearer to their grain-fields, and were carrying with them their young, etc. The route, from the old home to the new, was patrolled on either side by soldiers. Every now and then I saw one of these individuals rush aside, elevate herself on her hind legs, shake her head, and clash her mandibles. She acted as if she saw some danger menacing the marching column and would ward it off. Others climbed little twigs or tufts of grass and scanned the surrounding country from these elevated and commanding positions. Others hurried up the laggards and stragglers, and even carried the weak and infirm.

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]

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 assertion. 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 maxillæ 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 larvæ to pupate than it does the male larvæ, 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 anæsthetizes them by instilling a small amount of poison through that sharp and efficacious hypodermic needle, her sting.[85]