Sunday, November 23, 2008

A murmur of myrmecology

I see in the paper that Bert Holldobler and E. O. Wilson are on the circuit promoting their big new book The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies. Already the book is stirring up scientific controversy. Just what role do altruistic cooperation, complex communication, and division of labor play in evolution? Does natural selection act on individuals or groups? And what can we learn about evolution (and ourselves) from the lowly ants?

When I used to write for the Boston Globe, I could expect to get a free review copy of a big and expensive book like this. Not any more. I have ordered the book for the college library, with my name first on the reading list. I'm sure you'll be hearing about it later here.

In the meantime, I checked out the book's illustrious predecessor for another look, Holldobler and Wilson's The Ants. Eighteen years ago I reviewed it in my column. I called it "one of those granddaddy books from which a whole clan of lesser books will descend." Seven hundred hefty pages of ant lore. Everything you wanted to know about ants but were afraid to ask. As it turns out, these tiny, endlessly-active pests of picnic and pantry turn out to be irresistibly interesting.

The ants need their Homer, and Holldobler and Wilson have assumed the role. In spite of La Fontaine's best efforts to draw an edifying moral from the ant's industriousness, we tend to prefer the frivolously fiddling grasshopper. Not even Ogden Nash found much to admire in the ant's unceasing busyness: "Would you be calm and placid," he asks, "If you were full of formic acid."

Formic acid, which is widely used in industrial processes, occurs naturally in the bodies of ants and takes its name from the Latin for "ant" (formica). From the Latin root we also have the scientific name of the ant family, Formicidae, and a bunch of other ant words, such as formicary (a nest of ants), formicate (to swarm with ants), and formication (an abnormal sensation of ants crawling over the skin). The very thought of finding oneself on a formicating formicary is enough to make the skin crawl, and that alone may account for our determined efforts to put ants and their habits out of mind. Holldobler and Wilson claim that ants have been neglected by scientists, in spite of their ecological importance, which is considerable. The 700 pages of myrmecological lore in The Ants no doubt did much to remedy the situation. The Superorganism will do more.

The earlier book includes an anatomical atlas of ants from around the world, each drawn at kitten scale. Some have fat heads and some have thin heads. Some are sleek and some are hairy. Some are spiky and some are corrugated. All of them are ugly and, if we are lucky, they will stay in their formicaries. (Admitting, of course, that the most beautiful thing to an ant is another ant.)

The most unlikely thing about ant anatomy is that little threadlike nexus that attaches the back half of the body to the front half. Wasps get the credit for inventing the wasp waist, but ants are equally pinched-in at the middle. Surely that bottleneck must constrict communication between the two halves of the insect, and according to Holldobler and Wilson, a lot goes on in both halves.

Ants are jampacked chemical factories. They employ the most complex system of chemical communication of any animal. Their glands are endlessly active, puffing and squirting secretions for every purpose. When tastes and scents fail, there are other modes of communication -- tappings, strokings, graspings, nudgings, and antennations. Holldobler and Wilson lay it all out in endless detail, an unabridged Webster's of ant gab.

Sometimes ant communication runs dangerously amuck. We are given the example of a group of army ants that was cut off by rain from the main foraging party. The soldiers of the group were so strongly attracted to each other that they formed a "mill," going blindly round and round in each others tracks for a day and a half until all fell dead. One might ask how animals subject to such self-defeating behavior could reach the pinnacle of insect evolution, and maintain their dominance for 50 million years. This is surely the question the new book will try to answer.

So I sit here in the library waiting for The Superorganism with The Ants heavy in my lap and I marvel that we know so much about these creatures that the new book will address in their plurality. The two Harvard entomologists take note of the ant's particular ability to specialize when the need arises. Instead of a single individual performing all parts of a complex task (for example, check a larva, collect food, feed the larva), different workers devote their efforts to a single part of the task (checking, collecting, or feeding). The human analogy is the assembly line where one worker does nothing all day long but put in a particular screw. Apparently, the same mindless efficiency that caused assembly-line mass production to triumph in the human workplace also accounts for the evolutionary success of the ant.

It is a rather un-calm and un-placid kind of success. Which probably explains why those of us with less formic acid and bigger brains prefer to be out fiddling with the grasshopper.

Further Reading

Bert Holldobler and Edward O. Wilson, The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies.

Bert Holldobler's and Edward O. Wilson's The Ants is a monument of myrmecology. For a more spritely read, try the same authors' Journey to the Ants: A Story of Scientific Exploration.

If you have youngsters among your aqaintances, you will love to read to them John Ciardi's delightful poem John J. Plenty and Fiddler Dan: A New Fable of the Grasshopper and the Ant (1963). I can't find it on the internet, and it doesn't appear to be still in print, but you may find it in your local library.

Discuss this essay and more over on the Science Musings Blog.