COMMUNAL LIFE

“For where’s the state beneath the firmament
That doth excel the wasps’ for government.”

“What is not good for the swarm is not good for the wasp.”

AS the tendency of mankind to crowd into towns grows stronger the joys of country life and the workings of Nature are more and more excluded from the daily experience of humanity. In a few the primal love of the wild is too strong for suppression, and turning from the hot and noisy streets they find it a refreshment of spirit to meet our little brothers of earth and air in the wider spaces of their own territory.

We were walking through the woods one hot day in the middle of August when our attention was attracted by a stream of yellow-jackets issuing from the ground. They came in such surprising numbers and looked so full of energy that we stopped to watch them, and this was our introduction to the study of these “bold sons of air and heat,” although a perusal of Fabre’s fascinating “Souvenirs Entomologiques” had prepared us to feel a lively interest in them. We were at our summer home near Milwaukee, where meadow and garden, with the wooded island in the lake close by, offered themselves as hunting grounds, while wasps of every kind, the socialistic tribes as well as the extreme individualists of the solitary species, were waiting to be studied.

The Vespas that had aroused our interest received our first attention, and a nest in the ground proved to be a most convenient arrangement. Experiments that would have been dangerous to life and limb had we tried them with a paper nest hanging in the open, were easy here so long as we kept calm and unflurried. Intent upon their own affairs, and unsuspicious of evil, perhaps because they knew themselves to be armed against aggression, they accepted our presence, at first with indifference; but as we sat there day after day we must have become landmarks to them, and perhaps before the summer was over they considered us really a part of home.

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While poor humanity takes comfort in a mid-day siesta, wasps love the heat of noontide, and with every rise in temperature they fly faster, hum louder, and rejoice more and more in the fullness of life. The entrance to the Vespa nest was but an inch across; and once when they were going in and out in a hurrying throng, jostling each other in their eagerness, we counted the number that passed, one taking the entrances and one the exits. In ten minutes five hundred and ninety-two left the nest and two hundred and forty-seven went in, so that we saw eight hundred and thirty-nine or about eighty to the minute. This must be a strong swarm, wonderful indeed when we thought that it had all come from a single queen mother. We imagined how she had made an early start, digging a hole in the ground, building within it a paper comb with five or six cells around a central column, and laying therein some neuter eggs; how she had then spent a month in attending carefully to the beginnings of things, feeding the young larvÆ as they hatched, and watching over them through their childhood and youth; and then how her solicitude was rewarded by the filial devotion with which this first set of workers took upon themselves the labor of excavating, building, and feeding the young, everything indeed except the egg-laying. These queens, surrounded though they are by respectful and attentive subjects, have much the worst of it in our estimation, never going out, and passing their lives in a dull routine. Through the early summer only neuters are produced, but when fall approaches the future generation is provided for by the development of males and females. The activity of the little colony is limited by the season, for as the days grow colder the males and females leave the nest and mate, and a little later both males and workers lose ambition, become inactive and finally die, while the queens hide away in protected corners to reappear in the spring. The eggs and larvÆ, left unfed and uncared for, become a prey to moulds and to hordes of insects, and thus the swarm comes to an end.

We had once made some not very successful attempts to find out whether spiders had a sense of color; and seeing that the conditions were much more favorable with our present subjects, we thought it would be a good plan to test their knowledge of the spectrum. Providing six sheets of stiff paper two feet square, colored respectively red, blue, green, pink, and two shades of yellow, and cutting a circular hole four and one half inches in diameter in the centre of each, we began our experiments by placing the red paper over the nest so that the entrance was clearly exposed. The outgoing wasps dashed upward without noticing it, but great was the confusion among the homecomers. Thrown out of their reckoning, they clamored about us in ever increasing swarms. Like Homer’s wasps,

“All rise in arms and with a general cry
Assert their domes and buzzing progeny,”

and a crisis (for us) was approaching, when one, a pioneer of thought, determined to go into the hole, which did not look like the right hole, although it was where the right hole ought to be; and so potent is example that one by one the others followed. Three hours later they had become accustomed to the change, and went in and out as usual.

They had noticed the paper; that was plain enough, but did they notice the redness? To test this, we left things as they were for two days, and then substituted blue paper for the red. Again the confusion, the swarming of fervent legions, the noisy expostulations, the descent of one after another; but this time they settled down to their ordinary routine in a little more than two hours. On the following day we removed the blue paper, leaving the grass around the nest exposed; and this proved a new source of mystification, but not so serious as the others. At the end of an hour twenty-five or thirty were still buzzing about, needing the guidance of the blue paper to get inside, and entering at once when it was replaced. As we tried new colors from day to day a few of the wasps became entirely reconciled to our interference, and paid no attention to the changes, while the others grew more or less accustomed to the idea of mutability, and were but little disturbed, although they still showed their consciousness of each alteration by making a few circles before going in. We once placed some dark red nasturtiums on light yellow paper near the nest, and found that more than one third of the homecoming wasps flew to them and hovered over them before entering. When light yellow nasturtiums, nearly matching the paper in color, were substituted, only one out of thirty-six noticed them; and as the odor was as strong in one case as the other, it would seem that the color was the attracting force.

Our final color experiment was to let the blue paper remain for a day or two, giving time for all the wasps to become familiar with it, and then to leave it on the ground a foot and a half away, while replacing it with yellow. This gave a false nest surrounded by the color that they had been associating with the entrance, and a true nest surrounded by a new color. In the next ten minutes two hundred and seventy wasps came home, and every one of them went to the false nest. Many circled above it, others entered the hole in the paper, and some began to excavate, and made quite a depression in the ground; but gradually they found their way home. Three hours later seventy-six wasps entered the false nest in five minutes, and at evening they were still visiting it in goodly numbers; but on the next day we saw only two that were deceived.

On successive days we substituted red for yellow, green for red, and so on, always with similar results, although the wasps became more and more accustomed to the vicissitudes of their life, and after a time seemed to look for the hole itself without relying upon the color to guide them. They found their nest under a color new to them much more readily than when the paper was taken entirely away and the ground left exposed. Once when the green paper was around their nest, and the wind blew it over the hole so that they could not enter, at least one hundred collected, many of them settling in the false nest; when we lifted the green paper, leaving the hole free, only three or four entered, but when we put it back in place they rushed in six or seven at a time. It was plainly the color that directed them.

This was a nearly rainless summer,—a condition extremely favorable to wasp development. Nests multiplied and grew until the whole country-side complained, and no wonder, for houses were full of them, and at mealtimes they gathered at the table with the members of the family. How did they know when dinner was ready? It could not have been by the sight, unfamiliar to them, of cooked food; was it, then, through the sense of smell?

Many were the questions that we asked in vain of our Vespas, but here was one that they could readily be made to answer. We rolled up two bundles, one of nothing but gauze, and another, like it in appearance, but containing some warm chicken bones; these were laid to one side of the nest, the color of the gauze matching that of the paper on which it was placed. The wasps in returning to the nest, even though loaded with food, could not resist the appetizing odor, and settled thickly upon the bone bundle, trying their best to penetrate within, while the empty gauze was unnoticed. As the bones grew cold and dry they attracted less attention, but two days later they were occasionally visited.

Having killed two wasps that had alighted on the ground, by striking them with a folded paper, we took them up and placed one of them at a distance, so that it was entirely hidden in the grass. Five settled above it, and after they had carried it away the place was visited by several others, while the spot upon which we had killed them drew to it nine wasps within fifteen minutes. Thus they seemed very keen of scent where animal matter was concerned; but the powerful oils of peppermint and wintergreen, although noticed, aroused little attention, perhaps because they indicated nothing of interest to them.

Our experiments on hearing met with negative results. The wasps seemed insensible to any noise we could make or that we could produce by whistles of various degrees of shrillness. This of course does not show that they cannot hear, and any one who has been unfortunate enough to disturb them in the neighborhood of their nest will remember how their angry buzzing seemed to serve as a battle cry to gather all the members of the clan for the attack.

Our Vespas began to work an hour or two after sunrise, and did not stop until dusk. One cloudy evening when darkness fell early they continued to return to the nest, being able to fly to the right spot without any hesitation, although our vision did not permit us to see the opening without going down on our knees and looking closely. At last it grew perfectly dark, and we stuffed a handkerchief into the hole, with the result that seventy-five, coming home without a ray of light to guide them, were shut out, and were found clustered about the spot on the following morning.

We wanted to estimate the amount of labor done by a worker in a day, and so, rising one morning at the first bird call, we went out into the freshness of dawn, and for an hour had the world to ourselves; but a little before five a few straggling wasps that had stayed out all night began to bring in loads, and by half past seven they were fairly under way. From half past four until twelve we counted all that passed, 4534 going out and 3362 coming home; and with all this activity there seemed to be no pleasure excursions, for each one carried food when returning, and took out a pellet of earth when leaving. We once raised a little garden from the pellets that were dropped on our porch table where we kept a bowl of water. Wasps are great drinkers, and when they find such a provision they come frequently to refresh themselves, dropping their loads as they alight. This habit of holding on to their loads until they settle down may perhaps make them a factor in extending the boundaries of plant distribution, both under ordinary conditions and when, as must often happen with little creatures flying so high, they are blown to long distances from home.ill11

Having kept close track not only of the numbers, but of the hours, each count being made to cover five minutes, we were able to calculate that an average trip occupied forty-three minutes. When we met these wasps in the garden they never seemed to be hurrying, and had the air of amusing themselves; but they must be faithful workers to accomplish so much. The curious fact has been established that when food is very plentiful the workers begin to lay male eggs, thus taking from the queen a part of her burden and leaving her free to produce neuters and females. The nest that we were watching was found, at the end of the season, to contain 4661 wasps in various stages of development, and others that we opened had from two to four thousand. This is nothing to the social wasps of China, where a single household is made up of from fifteen to twenty thousand members; but China is a thickly populated country, and perhaps with wasps as with human beings several families live in a single domicile.

Outside of their wonderful social instincts our wasps are found wanting in the higher gifts of emotion and intellect. When we killed a number of them and placed them near the nest, their nearest relatives wasted no time in mourning, nor yet in revenge, but calmly cut up the bodies and fed them to the ever hungry young ones. If we placed some rich and tempting morsels at a distance, two or three would discover them, and would go back and forth all day without telling the others about it, as ants would have done under like circumstances. When we obstructed the opening to their nest by lightly laying blades of grass across, the day passed without its occurring to the wasps to lift them away, although they suffered the greatest inconvenience in getting in and out, crawling laboriously through, and in some instances giving up the task and flying away.

Vespa maculata, building on trees and fences, has practically the same habits as the ground wasp, germanica, the internal structure of the nest following the same plan, while the outer wall is of a papery substance like that of the combs, made from the scrapings of weather-beaten wood. The genus Polistes builds combs similar to that of Vespa, under porches or in any sheltered place, and does not inclose them. All these wasps, when adult, enjoy fruit and flowers as well as animal food; but only this last is used for the young, and many a caterpillar creeping along with sinister design is snatched by them to be chewed into a pulpy mass, and then fed to the larvÆ. No calculation has been made of the value of these wasps in agriculture, and one of the things that farmers have yet to learn is to encourage their presence in orchards and gardens.

Some species are said to sting the drones and larvÆ to death at the close of the season, but this habit is not followed by V. germanica and V. maculata. Since there is no store of provision to be economized through the winter the only object of such conduct would be the merciful one of ending their sufferings at once instead of letting them perish by slow starvation, and we find no evidence for such elevated ideas. What makes for the welfare of the species they thoroughly attend to, but beyond that point they do not go.

The socialism of wasps is in a less evolved state than that of bees and ants, and yet there is in it sufficient sacrifice of self to the common good to excite the respectful wonder of human beings, whose relations to each other and to the state have such different standards.