The Homing Instinct: Meaning and Mystery in Animal Migration. Bernd Heinrich

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СКАЧАТЬ probably because one gets fed less and then weakens and eventually starves. Presumably through evolutionary history, for the fast growth required to reach full development and readiness to migrate by August, there has not been enough food to raise two colts at once. One might suppose the cranes could simply lay only one egg, but sometimes an egg does not hatch, and the second is insurance.

      The pair seemed more animated after their last fight with the lone intruder, and by evening they again mated (for at least the third time that day). In most birds one mating is enough to fertilize the eggs. Perhaps several matings are insurance, but this seemed more than enough for insurance. Perhaps, like their dances, mating is additionally part of their bonding ritual.

      A pair of mallards, and then a pair of pintails, arrived in the evening, and the ducks swam next to each other near the cranes at the edge of the pond, where some open water had reappeared during the day. The cranes ignored them and again walked in their stately manner back and forth across the ice of the pond, and now they pecked in the low vegetation being exposed along the edges. They were by now finding overwintered cranberries exposed by the melting snow.

      On the evening before I would leave for my journey home, Christy and George hosted a potluck party. Shadows fell on the white frozen middle of the pingo as the western sky turned yellow and orange and the spruces became dark silhouettes. A pair of pintails again landed in the open water along the pond’s edge. The cranes were standing, each on one leg, their heads tucked into their back feathers. People crowded around the spotting scope in the living room, watching them occasionally shift position, lower a leg, poke a head out to look around. Suddenly the person then at the scope erupted with an exclamation: “They are mating!” She had seen the male approach the female with her spread wings, mount, flutter, and jump off. The pair had bowed to each other. Suddenly many people crowded around the scope to watch.

      Why, I wondered, would anyone, or almost everyone, want to watch cranes mate? Why was nobody interested in watching the mating activity of the two ducks, or of the numerous redpolls? Could it be, I wondered, because we feel a closer kinship with cranes than with other birds?

      Cranes are similar to us in many ways. Some are nearly as tall as a person. They walk on two long legs like us, albeit with a much more graceful and deliberate gait, so that they remind one of a caricature of a gentleman or an elegant woman on a leisurely stroll. The sandhill crane’s red bald pate and sharp yellow eye add to the caricature. Cranes form lifelong pairs and stay together as families, but they are also gregarious and join up into large groups. They form a strong attachment to their home. They not only make music with trumpeting calls that sound like bugles, but they also dance, and do so on various occasions.

      All of the fourteen species of the world’s cranes dance. Crane dancing involves running, leaping into the air, flapping the wings, turning in circles, stiff-legged walking, bowing, stopping and starting, pirouetting, and even throwing sticks. Dancing is primarily done by pairs and presumably functions in cementing pair bonds and/or synchronizing reproduction. But it can also be induced at any time, and it stimulates other cranes to dance. Even the young colts perform some of the species’ dance. Possibly it serves as practice and could be motivated by the same basic emotions of joy that are an indicator of health important to mating.

      Cranes’ dances often stimulate humans to dance as well and have been mimicked in many cultures all over the world where cranes live. Crane dances were performed by ancient Chinese, Japanese, southern African, and Siberian people. If not emulated, cranes are admired. In the Blackfoot tribe of Native Americans of northern Montana, the last name “Running Crane” is common.

      Nerissa Russell, an anthropologist, and Kevin McGowan, an ornithologist from Cornell University, revealed that eighty-five hundred years ago at a Neolithic site in what is now Turkey, people probably performed crane dances using crane wings as props that were laced to the arms. Furthermore, someone of these people apparently hid a single crane wing in a narrow space in the wall of a mud-brick house along with other special objects (a cattle horn, goat horns, a dog head, and a stone mace head). Russell and McGowan also found evidence that vultures may have been hunted for their feathers for presumably a much different costume worn as well for a ceremonial purpose. The authors inferred that the cranes were linked with happiness, vitality, fertility, and renewal (since they arrived in the spring). While the crane dance was one of life and birth, and possibly marriage and rebirth, the vulture dance was associated with death and perhaps return to the afterlife.

      Russell and McGowan believe that the crane wing interred in the wall of the house was never intended to be seen. It was a symbolic object related to marriage and construction of a new home and may have been coincident with a particular human marriage and home-making. The associations among dancing, pairing, and raising young and home would have been natural for people who saw cranes return to their home ground, just as I had seen Millie and Roy do. Seeing the close parallels in the biology of the birds with their own lives, and understanding the cranes’ dancing as helping to make or cause the good things that followed, Neolithic people would have been compelled to symbolically emulate the crane dance of homecoming and of new life.

       BEELINING

       Observation sets the problem; experiment solves it, always presuming that it can be solved.

      — Jean-Henri Fabre

      CRANES FLY AN ENORMOUS DISTANCE TWICE ANNUALLY, BUT relative to their size, bees also fly huge distances — up to ten kilometers — and the foragers may perform such trips hourly. We can experiment with them to find out how they navigate. What we know about bee homing so far is nothing less than astounding, and it is built on a long history of research, primarily pioneered by the imaginative experiments dreamed up and performed by an Austrian named Karl von Frisch and his colleagues that date back over a half-century. Arguably, our knowledge dates back still further to early American frontiersmen trying to find bees’ treasure troves of honey.

      In 1782, Hector St. John Crèvecoeur, a writer and farmer from Orange County in New York State, wrote:

      After I have done sowing, by way of recreation, I prepare for a week’s jaunt in the woods, not to hunt either the deer or the bear, as my neighbors do, but to catch the more harmless bees … I proceed to such woods as one at a distance from any settlements. I carefully examine whether they abound in large trees, if so, I make a small fire on some flat stones, in a convenient place; on the fire I put some wax; close by this fire, on another stove, I drop honey in distinct drops, which I surround with small quantities of vermillion, laid on the stones; and I retire carefully to watch whether any bees appear. If there are any in the neighborhood, I rest assured that the smell of burnt wax will unavoidably attract them; they will find the honey, for they are fond of preying on that which is not their own; and in their approach they will necessarily tinge themselves with some particles of vermillion, which will adhere long to their bodies. I next fix my compass, to find out their course — and, by the assistance of my watch, I observe how long those are returning which are marked with vermillion. Thus possessed of the course, and, in some measure the distance, which I can easily guess at, I follow the first, and seldom fail of coming to the tree where those republics are lodged. I then mark it [presumably with his name to claim ownership].

      James Fenimore Cooper, author of the Leatherstocking Tales of the American frontier, of which The Last of the Mohicans is probably best known, in 1848 published the novel The Oak-Openings; or, The Bee-Hunter. Here Cooper depicts a different, perhaps more reliable method than Crèvecoeur’s of the frontier activity that came to be called “beelining.” Cooper’s story takes place during July 1812, in the “unpeopled forest of Michigan,” where, due to the Native Americans’ lighting periodic fires to clear the ground, there were many flowers among the scattered oaks. This was ideal honeybee habitat, and here the bee hunter СКАЧАТЬ