Ants at Work
How an Insect Society
(The Free Press)When I was growing up in the South, our house was on the edge of town, so the terrain nearby was chock-
a- block full of fire ants. When we would go out to play, at some point my sister --- ten years of age to my seven --- would motion to one of the nests, and say, "Stick your hand in there." "Naw!" I would say. She would look at me crossly, her eyes narrowed, and say, clearly enunciating each word, "Stick. Your. Hand. In. There."
I had the choice of being bitten by fire ants or dealing with my sister, so, my eyes filling with tears, my chin quivering, I would slowly extend my hand down until she, impatient, grabbed it and jammed it in the mound so that what looked to be a thousand or so not-very-amused red-and-black ants would go for me, mandibles working, until I yanked it out and ran screaming in the house.
"What's wrong now?" Dilsey would say, in the cool reaches of the kitchen. "She made me...she made me..." I sobbed. "She made you what?" said Dilsey. "She made me stick my hand...in the ant pile."
"Boy," she'd say, turning back to the stove. "You shouldn't be going 'round making up stories like that."
Ever since those days, I've been able to temper my affection for ants, fire or no, but there are people out there, like Deborah Gordon, who apparently can't get enough of them. She goes out in the Sonoran Desert all hours of the day (120 degrees; average windspeed, 25 knots) to observe the red harvester ant, Pogonomyrmex barbatus. What she is trying to figure out is how they work. Or, as she puts it,
The basic mystery about ant colonies is that there is no management....There is no central control. No insect issues commands to another or instructs it to do things in a certain way. No individual is aware of what must be done to complete any colony task.
There are five elements of an ant colony. There is the queen, once thought to be in charge, but, in truth, no more than an egg-laying machine. There are those who do nest maintenance. There are the "middens" --- in charge of the garbage collection. Finally, there are the foragers who go out and bring home the bacon (in this case, seeds), and the patrol detail, whose task is to protect the colony.
Ms. Gordon is so enthusiastic about her calling as antperson that she has been going to the same place in the Sonoran Desert for years to study a certain small area that contains 300 or so harvester ant colonies.
Her task is not just going out there to sit on her duff and watch their comings and goings. She measures the area and the paths each colony uses for gathering seeds; she counts the ants; she marks them with distinctive colors, to figure out whether (for example) the middens ever become foragers. On occasion, she will even rent machines to dig up the whole damn mess so she can peek at the internal structure. ("You want me to go out there in this sun and dig up a bunch of ants," we imagine the backhoe operator saying.)
At other times, she will drop seeds in the foragers' path to see how they react to this act of god; occasionally, she will pop a few alien ants into the nest to watch the reaction; she will, from time to time, even wrest a seed away from a startled ant,
If you tap the ant's head gently with a twig it usually opens its mandibles out of sheer astonishment, dropping the seed. (The exception is when the ant has had the amazing good fortune to find a termite; then nothing will induce the ant to let it go.)
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Gordon is a worthy researcher, and, more importantly for us, a good --- and often funny --- writer. For instance, part of her research entails making maps so she can return to the area to locate the colonies she had been studying in earlier years (she's been doing this nonsense for over fifteen years now). She wanted to "track colony age with maps that could be used to follow labeled colonies from one year to the next."
We started out using a triangulation method, until I figured out that no amount of trigonometry would change the fact that if the location of one colony is measured as its distance from another, error will accumulate at an astonishingly high rate. We also wasted a lot of time bickering in the hot sun about sines and cosines....
Such calculations became difficult at the hot end of the morning, and some people seem to have a bias toward calling east west, or north south, leading to endless arguments later in the afternoon when we tried to put the newly measured colonies on the map and found them in strange places way off the site.
Even for those of us with little or no enthusiasm for ants, there are astonishing facts buried, like desert seeds, all over Ants At Work. If she survives the first migration, and lives through the first hard years, the queen will live for a full fifteen years, although the lifespan of her spawn is but a single year. Younger colonies have different patterns than the older ones --- and those three or four years old tend to be more aggressive in fighting over territory and hellraising in general.
Busybodies like Gordon can bring seed and dump it in one of the foraging paths, but often, it will not affect the established patterns. If a small number of the patrolling ants are plucked up and spirited away, the colony will continue as before; but there is a crucial number that causes the whole colony to shut down. Strange ants plopped down in the middle of the colony may be ignored, unless they are from nearby colonies.
Most of all, ants aren't very smart, and, she opines,
Emulating ants does not improve one's character. A person with the moral qualities of an ant would be terrifyingly empty. And I have not learned much about people from watching ants. People remind me of ants only when seen from so far away that they no longer resemble people; in the movie Titanic, the passengers scrambling up the sinking hull seemed to behave like ants.
If, for some fool reason, you and I wanted to spend a summer in the Southwest desert --- swatting sandfleas and sweating, being stung often and well by the subjects of our investigation --- then we could do no better than to join up with Dr. Gordon. However, we're probably better off reading Ants at Work. It certainly is cooler, and a helluva lot more fun, I'll wager.
--- Ignacio Schwartz