All week, I’ve been accompanying Chris Nagano on his winter rounds. Chief entomologist for the Monarch Project, Chris is a slender, mustachioed young scientist with a lively sense of wonder. He takes me to the Ellwood site in Santa Barbara, where monarchs have been monitored for the past thirty years. A cloud of butterflies drifts low through the gulley and above a bank littered with the leprous bark of the eucalyptus, which flakes off the trees and lies on the ground like endless rolls of papyrus. There are few crawling insects; the eucalyptus oil keeps them away. A Pacific tree frog begins a long croak that sounds like someone working the tumblers of a safe. There is an artillery of falling eucalyptus seeds, whose hard, sharp nosecones hit the soft dirt with a relentless plopping. Creaking timbers make you think someone is constantly opening and shutting a door. The pungent smell of eucalyptus fills me with memories of Mentholatum rub and childhood colds.
We must tag at least two hundred butterflies at each site for our data to be statistically useful, so Chris takes a specially designed pole with a long net at one end and extends it high into a tree, scooping about seventy-five butterflies into its cornucopia-shaped maw. Fluttering madly in the net, their wings sound like a drizzle falling on dry leaves. Chris lays his green army jacket gently over them, “so they don’t get agitated,” and we sit down in the sunlight, in what might be an Indonesian forest, and begin lifting the butterflies out of the net, one by squirming one.
There is an art to tagging a butterfly. First you hold the soft, trembling body in your left hand, securely, although you can feel it gently quivering. With your right hand, you separate the front and back wings as if you were sliding one playing card behind another. Then you rub off a small oval of colored scales with your thumb and forefinger, until the clear cellophane of the wing appears. Children often are taught the old wives’ tale that if you touch a butterfly’s wing, you’ll wipe off its “flying dust” and ground it permanently. But the microscopic scales are dead, like fingernails or hair. Tagging doesn’t hurt the monarchs, nor does careful handling. Onto the clear window in the wing you press one half of the sticky, stamplike tag, then fold the other half over the top of the wing and press it firmly. Next, with both hands, open the wings of the butterfly to see if it’s a male or female. Males have two black dots low on their wings and scent pouches (the scent is probably to alert other males rather than to attract females). The females have no black scent pouches, but they have thicker black veins for conducting heat to the body. On a prenumbered sheet, record whether you have a male or female, and indicate its condition: a 1 means perfect, a 3, battered and worn. A flawless specimen will have a radiant blue sheen and vibrant, velvety wings of deep orange and buff, on which loud islands of color float, some blurred, some clear-edged; a frilly white spotted hem around the bottom of each wing; and a body covered in a thick, mink-colored fur.
If it’s a female, check to see if it’s pregnant by lifting up its soft abdomen and feeling it between thumb and forefinger. The sperm a male deposits inside a female is thick with protein and vitamins, and it feels as hard as a ball bearing. I jot down “F2V,” which means I’ve just tagged a female virgin in average condition; other numbers indicate the capture site. It is chilly in southern California in the winter, and monarchs can’t fly much if it’s below 55 degrees Fahrenheit. They would rather cluster to stay warm than shiver, the way other animals do, but they will shiver if they have to. One stands quaking on a log. Chris lifts it up, places it like a fluttering gold cookie in his open mouth, and breathes warm air over its muscles. Its four tiny black feet flex, and when he tosses it into the air, it flies eagerly back to its cluster high in the tree. As it approaches, all the other butterflies flap their wings to warn it not to cover them. They need the sun. It hovers, then finds a free spot lower down, clinging with its sticky two-clawed feet. All four feet are pronged like a longshoreman’s steel grapple. Lift one foot free and the other three will snag tight.
Over the hill appears a class of teenagers from Bishop, about a six-hour drive inland. They are on a biology field trip to study the creatures of the tidepools, as well as the monarch butterflies. Chris ad-libs a lecture on the insect’s life cycle, noting that the black-and-white-striped caterpillar from which the adult butterfly will emerge feeds only on milkweed, which contains a heart-stopping poison favored by assassins in ancient Rome. In turn the butterfly’s body will carry enough poison to sicken a hungry bird. He shows them a butterfly with a beak-shaped bit of wing missing; the butterfly can still fly, and the bird will have learned not to attack others of that color and pattern. Indeed, the viceroy butterfly, though it is not poisonous to birds at all, mimics the monarch’s color as a defensive sleight-of-hand.
A couple of the boys pass a football back and forth, but most of the students are rapt. Chris urges them to try their hands at tagging.
“Oh, he’s so mushy!” a girl squeals as she lifts one up. Instead of rubbing with her fingers, she pulls her long red fingernails across the scales, which doesn’t make the job any easier. When the butterfly flails its threadlike legs, she squeals again but doesn’t let go. “Do they bite?”
Chris explains that they don’t, can’t, are completely harmless, hunt nothing, hurt no one, but are “pretty tough bugs” nonetheless.
She rubs a perfect window into its wing, sticks on the first half of the tag, then folds the next half over. “His antenna’s caught under the tag!” Chris lifts it free, checks the sex. Female.
“Number 478 is a female.” He jots in his notebook.
Grinning, the girl tosses it high into the air like a fighter pilot launched from an ejection seat.
Classes seem to be attracted to Chris when he’s tagging. It can take a long time to allow a whole class to handle butterflies, but one day when an environmental issue comes up they’ll remember. It’s hard to learn about animals if you only see them dead on dissecting trays.
At Pismo Beach, up the coast, a park ranger comes by with a class of preschoolers on a butterfly tour. It is a brilliantly sunny day, and the butterflies are busy running their errands. Some arch their wings wide like solar collectors and sit in the direct sun. Some cluster high in the trees. Some sip dew from the grass (though they must be careful of the yellow jackets on patrol under the trees, looking for injured monarchs to kill and eat). Some collect nectar among the wildflowers. Some mate. Monarchs don’t go in much for courtship. The male yanks the female right out of the air, hurls her to the ground, and attaches himself. Then, still attached, he flies off, with her dangling below, wings closed, as if she were a tan purse he was carrying, or he were returning a dropped hanky.
Seated on the fragrant floor of the eucalyptus grove, where insects are scarce and the ground is covered with the succulentlike South African ice plant (one of the few that can bear the heavy eucalyptus oils), we settle down to serious tagging. I deliver the kiss of life to each one, to warm its muscles, before flinging it back into the sky like a piece of solid confetti. Sometimes their faces are smeared with yellow grains of pollen. They all differ in shape, coloring, personality. Though many butterflies live only one day, overwintering monarchs live six to nine months. After tagging the first hundred, my fingertips are coated yellow-orange from the scales.
On my last night in California, after a week of tagging thousands of monarchs, I stop brushing my teeth when I hear a commotion in my motel room. There is a fireplace in my room at the Butterfly Grove Inn, and a wayward monarch has apparently flown down the flue. In a panic, it careers around the ceiling. I open the door to the porch. At last it settles on the warm lampshade and I grab it by the wings and carry it outside, hoping it will find its way home in the dark. The next morning I awake to such a screeching and scratching that I leap out of bed and rush to the porch. A blue jay, pacing angrily on the railing, screeches as it cocks its head toward the floor. There stands a monarch, shivering and stunned, with a beak-shaped wedge bitten out of one wing. Because I’m not awake enough to know better, I make a fist and lunge toward the
blue jay to punch it in the chest. But before my hand can touch its feathers it disappears straight up. Gently, I pick up the monarch, check the wing. Not a bad injury really; it could fly. I open its wings to have a better look at it. A female. Not pregnant. I haven’t any tags with me, or I would tag it. Instead, I walk across the yard with her, to where thousands are clustered high in the trees; I blow warm air over her muscles and toss her into the air. After free-falling a moment, she discovers that she’s airworthy and flies up to her clan, some of whom are planing across the sky.
It’s easy to get mesmerized watching the monarchs glide overhead, with the sun shining through their wings, as if they were small rooms in which the light had been turned on. A cluster trembles on a branch; then, in a silent explosion, they burst into the air and fly down to a Christmas pine in the direct sun near the road. Sitting on the tips of the branches with their wings spread wide, they might be orange and gold ornaments. They are silent, beautiful, fragile; they are harmless and clean; they are determined; they are graceful; they stalk nothing; they are ingenious chemists; they are a symbol of innocence; they are the first butterfly we learn to call by name. Like the imagination, they dart from one sunlit spot to another. To the Mexicans, who call them las palomas, they are the souls of children who died during the past year, fluttering on their way to heaven.
INSECT LOVE
Yet let me flap this bug with gilded wings,
This painted child of dirt, that stinks and stings;
Whose buzz the witty and the fair annoys,
Yet wit ne’er tastes, and beauty ne’er enjoys.
—Alexander Pope
There are only two seasons in Ithaca, and both of them are wet: hot wet and cold wet. In August, part of the hot wet season, caterpillars suck the life from rose leaves, prenuptial ants grow wings and take to the air, armadas of tanklike sow bugs pour across the patio, hypodermic sphinx moths sip nectar from the phlox, monarch butterflies, mating in midair, look like an invisible magician’s card trick, and countless other insects swarm in, under, atop, and through the grass, invade the house beams, or patrol the sky.
On such a hot, steamy evening, I decide to join an entomologist friend, Thomas Eisner, in his laboratory at Cornell University. Some people travel to the ends of the earth to discover the exotic, that ever-receding land that adds so much to life’s cartography, but what I’ve always liked about Tom is that he ushers the exotic into his daily life. He can find it on a doorstep, at a golf course, in an abandoned lot, beneath a derelict building, along an air-conditioned hallway. Blessed by an elastic curiosity that stretches, changes shape, and snaps back like a thick rubber band, he is—in the very best sense—distractable. It’s not unusual to hear that he’s away in an unkempt field because some fascinating animal has kidnapped his attention.
At times he can be candid about his gift for “discovering things” (over the years, his work has been featured on the cover of Science more often than anyone else’s), but he can also be almost masochistically modest, presenting himself as only a bit player in the high drama of life. Yet by worldwide proclamation he is “the father of chemical ecology,” a field of study devoted to the chemical relationships among all living things. Not only does he see the forest for the trees, he knows how insects see that forest, too, and how the trees, looking back, flirt with and seduce the insects into ingenious liaisons. He knows how insects communicate with one another through the chemical calling cards we name pheromones. We’re indebted to him for much of our understanding of insect defenses and courtship. He and his research partner, chemist Jerrold Meinwald, have made many practical discoveries, too, including nerve drugs in millipedes, cockroach repellent in an endangered mint plant, heart drugs in fireflies, and how the dangerous aphrodisiac “Spanish fly” works.
On the fourth floor of Mudd Hall, a large brick building in mid-campus, sits Eisner’s laboratory. I enter the office of his secretary, above whose door hangs a glass business sign: CORNELL BEAUTY SHOP. It’s wired so that a wolf whistle will turn it on. Then I walk left through the door to his private office, above which a printed sign says: COME RIGHT IN, WE’RE CLOSED. On his desk sit many framed photographs of his wife of over forty years, Maria (also an entomologist), their three daughters, and their six grandchildren. At eye level on the wall, a plaque from his artist daughter credits him with being a “BioAstrology Destiny Reform Specialist,” which she thought sounded more like her dad than “entomologist.” The walls are a mosaic of compelling twenty-by-twenty-inch photographs he took through a microscope. At first they seem to be complex, colorful abstract designs, but each one shows an insect caught in an extraordinary behavior. There is a bola spider, for instance, holding what looks like a yo-yo at the bottom of a silk thread. The spider spins the bola around, lariat-style, and hurls it to capture its prey. Right at the end of the gallery is his prize: an enlarged photograph of a bombardier beetle in the act of zapping a foe. At the tip of its abdomen, a gun turret fires a jet of scalding chemicals. Harmless when stored separately, the chemicals combine in a special gland and become volatile as nerve gas. A master of defense and weaponry, the bombardier can swivel its gun turret, aim straight at an intruder, and fire a twenty-six-mile-per-hour blast of searing irritants, not in a continuous stream, but as a salvo of minute explosions. This “pulsed jet” is oddly similar to the propulsion system used in the German V-1 buzz bombs of World War II.
Through the next doorway I see Tom, standing pensively at a lab table, looking down into two shallow plastic bins of the sort one might find in a pantry. Tall, wiry, he has a face with many planes and inclines. One can imagine a fly rappelling down his cheekbones. He has blue eyes and wears glasses. Combed back close, his dark hair gives him a Latino flavor. In his twenties he actually wore an El Greco beard and mustache, but now there are few visible traces of the adolescence he spent in Uruguay. I don’t know another scientist who has a Steinway piano in his lab—or, for that matter, a poster of Marilyn Monroe wearing black fishnet stockings and a Merry Widow bustier from which her ample bosoms seem to be tumbling.
“Come on in!” Tom calls when he sees me. He takes my hand in a strong handshake, then wraps his other large hand on top of that and squeezes. “I’ve been working with some of my favorite bugs—bombardier beetles.” He leads me to the two plastic bins, filled with damp sand and small aluminum-foil tents splattered with beetle excrement. The tiny encampment looks still. As I bend down for a closer look, a nose-twitching whiff of something like semi-decayed duck sauce hits me.
“Where are they?” I ask.
He smiles and lifts up the silver tents. Dozens of beetles swarm over one another and dart into the corners. Blue-backed, each has a tawny plump belly, a tiny head and thorax the brown of a Stradivarius, two long antennae, and six many-jointed black legs.
“Want to hear them fire?” he asks cheerfully. I nod yes. “Okay, just reach into a mass of them and press on one a little.”
“All right,” I say slowly, leaning closer to one of the bins. For a minute or two, I stand frozen to the spot, eyes glued to the insects. Catching my breath, I realize that I’ve been twisting the bottom of my black cotton sundress into a large knot, as if I were wringing it out. Tom touches my arm reassuringly.
“Take your time,” he says softly.
Raising my index finger, I direct it by willpower to move horizontally just above the bin, and vertically down an invisible elevator shaft to the damp sand. Minutes pass. Then, sliding my finger toward a crowd of beetles, I feel their legs and antennae brush my skin lightly. My right eye automatically squints tight. Another minute passes. At last I lift my finger and press it into a bunch of beetles, and pop!, one fires a shot. Startled, I jump back, laugh, reach in nervously and press another button-shaped back, hear another beetle fire, reach in again—this time eagerly. I’ve triggered the artillery, and now my index finger has three brown stains on it—the stigmata of the beetle handler—arranged like two small eyes and a mouth. Smiling at the impromptu finger p
uppet, I remember being eleven, rapturously watching “Mr. Wizard” on TV, and yearning to muck about in his lab. My index finger has browned like the exposed flesh of a freshly bitten apple. Bombardier beetles carry quinone in their saddlebags—an aromatic compound found in antibiotics and some plants (such as stinkweed), and used by humans for making dyes, tanning leather, and processing film. In fact, the bombardier is a diabolist with light. A desert dweller with a dark body, it lives on light-colored sand and, when threatened, splashes the intruder with its equivalent of Mace.
Because the bombardier possesses the only jet engine recorded in an animal, insect fanciers are especially fascinated by its engineering. To squirt, it pulses at a rate of five hundred to one thousand times per second. No muscle could move that fast. Instead, a passive oscillator guides the necessary chemicals into a reaction chamber, where they mix, causing a small explosion, which geysers the liquid up and out of a nozzle and at the same time closes the vent that fed liquid into the chamber. After the firing, the pressure is relaxed, the vent opens, and more liquid enters the chamber. In this way, the beetle rearms.
Bombardier beetles have a very high defense budget. It takes a lot of food to fuel such weaponry. So the beetle must forage very effectively, which means it’s bound to lead a stressful existence, hunting without much concern for safety. Of course, it can afford to do that because it’s so well protected. So here we have the classic vicious circle of the weaponeer: feverish hunting for resources to keep the defenses strong to enable it to be feverish.