Dinosaurs in the Attic
Page 21
PERIPATETIC ROACHES (AND OTHER INSECTS)
Paradoxically, the study of insects, while seemingly obscure, is the systematic science that most often has direct consequences for the average person. While a new discovery about, say, gorillas may be fascinating, a new discovery relating to cockroaches could affect millions of people. Indeed, the Museum's Entomology Department receives thousands of queries and requests a year for information on insects—mostly on how to get rid of them. One such problem is worth recounting. Several years ago a Museum research associate was called upon to solve a tricky problem for the New York City Transit Authority. The problem was brought to the attention of the TA by dozens of letters, of which the one below is an example:
Dear Sir,
I'm hoping this is not another exercise in futility. Letters of complaint are so easy to ignore, so I rarely, if ever, write them. It seems only the danger of public exposure produces any effect.
Most of the time, despite momentary flashes of anger, one can shrug off the indifference, hostility, and even outrageous rudeness unleashed by bus operators on the unfortunate riders of the New York City bus system.
But roaches!!! And from the many sizes, second generations of them!! How dare you inflict this on those who support your system, pay your salaries, and put their trust in you. Roaches—I will not sit still for them. This horde of roaches was on bus number 8553, October 4, 1979, at 2:50 P.M.
This obviously bespeaks gross negligence as well as total indifference. Littered buses, soiled windows—bad enough. But vermin? I can't imagine the heyday the media would have with such a news item, and unless something is done, and fast, I shall do everything in my power to see that it is publicized.
A Disgusted Rider
Cockroaches, as it turns out, have been riding the city's buses for over fifty years. Generally they have kept a low profile and stayed out of trouble. But around 1979, a minor population explosion took place on the city's buses. The Transit Authority tried one ineffectual remedy after another without any success, until finally, in desperation, someone from the TA called the Museum.
Joseph DeVito, director of safety at the TA at the time, explained the problem: "A few years ago, the TA embarked on a program of bus washing. But believe it or not, the more we washed the buses, the more complaints we got about the roaches." In response, the TA stepped up its insect bomb and fumigation program; but the itinerant roaches, like roaches everywhere, held fast to their domain, and bus drivers complained of the fumes. Other remedies were attempted. One ingenious engineer even rigged up a grid of live wires at a roach hangout on a bus, but after several roach electrocutions the bugs learned to avoid the trap.
It was at this point that a TA executive suggested that an entomologist might be able to help. "We hoped," explained DeVito, "that by studying roach behavior, perhaps there would be a way—something like the Pied Piper of Hamelin—to get the insects to march right off."
Dr. Betty Faber, a research associate in the Entomology Department, offered her expertise free of charge. The TA gave her a transit pass and she began riding the buses and visiting the terminals, jotting down the behavior of the stowaway roaches in her field notebook.
Faber is experienced in roach-watching. For her research she keeps a colony of wild roaches in the greenhouse on the roof of the Museum, where they share quarters with electric eels, black-jawed fish, and various plants. Faber provides her roaches with protection from insecticides' (with large warning signs posted around the greenhouse), but the roaches have to shift for themselves when it comes to food and water. Faber herself traps most of the wild roaches, and affixes numbered strips of tape to their backs so she can tell one from another. At night, Faber observes her wards using a sophisticated infrared scope similar to the kind the army uses for seeing in the dark. She has also set up closed-circuit TV cameras so that she can watch the roaches from her office.
The cockroach, Faber explained, is one of the earth's most venerable animals. A cockroachlike insect was one of the first animals to colonize the land hundreds of millions of years ago, and its ancestors have thrived ever since. Its survivability is due, in part, to the fact that it has been able to adjust to changing environments. For example, fossil roaches have been found within the same strata with dinosaur bones, indicating that they probably ate dinosaur flesh. They seem equipped to survive as well in spotless Park Avenue kitchens as in steaming Cretaceous swamps. Hungry roaches have even been known to eat the inner organs of television sets and refrigerators.
The roach's adaptation to city life is nothing short of remarkable. Despite vigorous efforts to eliminate them,. they can still be found at some of the best addresses and some of the finest restaurants in New York. (Faber told us about one exclusive New York restaurant that discreetly contacted her about a desperate roach problem.)
Faber explained that the bus-riding bug is usually the German cockroach. Long a victim of wanderlust, this peripatetic creature immigrated to New York City from Asia (not Germany) at least a century ago, and has since established itself as the dominant species. (The larger American roach, sometimes erroneously called a waterbug, is still very much around, however.) Like most cockroaches, the German roach is strongly attracted to water. After looking into the TA's problem, Faber suggested that the bus-washing program, which started before the infestation, might actually have exacerbated it by making the buses a wetter and more appealing environment for roaches. People eating on buses provide roaches with food, and Faber noted that eating on buses has gradually increased over the years. The third ingredient for cockroach comfort—warmth—is provided by the engine and heating system.
But the real question Faber faced was how roaches got on the buses in the first place. "A roach," said Faber, "could conceivably climb on a bus while it is sitting in the terminal. But the terminals are actually kept very clean, and most are unheated. Anyway, it would be like climbing Mount Everest for a roach to get on a bus."
After some thought, she came to a definite conclusion: "Roaches get on the bus riding the passengers, and then get off the passengers once on the bus. These German roaches will hang on for dear life when disturbed or upset, and a perfectly clean person could be carrying a roach around in his clothing this way."
Unfortunately, Faber had to tell the TA that there was nothing it could do to eliminate roaches. She recommended simply that the buses be kept as dry as possible, and free of rubbish, especially in the rear seat areas, where the roaches were most noticeable. This approach may prevent roaches from staying too long on the bus, but it won't prevent them from getting on with riders. That problem, Faber felt, was insoluble. "After a point," said Faber, "there isn't much you can do about roaches except to learn to live with them. Roaches are a lesson in humility for all of us humans."
Roaches are not the only live insects in the Museum, however. One of the most celebrated "pet" collections belongs to Alice Gray, Senior Scientific Assistant Emeritus at the Museum. Gray and her menagerie live in a sunny tower office on the Museum's third floor, commanding spectacular views east across the park and south down Central Park West.
Miss Gray is a kindly lady in her seventies, a little hard of hearing, and a veritable storehouse of information about insects. Anyone who calls the Museum with questions about insects is referred to Miss Gray. Visitors with scurrying things in shoeboxes and jars are told to go to Miss Gray. She and her menagerie have appeared on such TV programs as "To Tell the Truth," "What's My Line?" and "The Mike Douglas Show."
Scattered about Gray's office, which she shares with the Origami Society of America, are mayonnaise jars, glass cages, and plastic boxes crawling and rustling with exotic creatures. One of her favorites is a colony of three-inch-long Madagascar hissing cockroaches, surely one of the most horrific insects in existence. When disturbed, the Madagascar cockroach emits a loud, evil hiss by drawing air through spiracles in its chitinous shell. (Gray explains that the spiracles are also used in molting; the insect simply sucks air into them until the
pressure bursts the skin along its back.) Cockroach enthusiasts, of which there are many on the Museum's staff, are delighted to find numerous rare species in Gray's collection, including bright green Cuban roaches, lobster roaches, and species from Central America, as well as the old standbys—the American and German cockroach.
The grande dame of Gray's collection, though, isn't an insect at all, but a large tarantula named Blondie. Gray raised Blondie from infancy in the Museum, and the giant spider—the size of a small salad plate—is tame enough to be picked up and handled. Gray has other tarantulas, but most are too "frisky" to tolerate handling, she explained.
With such a large collection of insects, some are bound to escape. Many years ago, one of her tarantulas escaped from its cage and was gone for several weeks. Then one day she received a call from someone who had found a tarantula wandering about in Central Park about four blocks north of the Museum. Gray recognized it, she said, "by the balding pattern of hairs on its abdomen."
Another famous escape scene occurred in 1979 during the Museum's special exhibition, "Pompeii A.D. 79." One of Gray's favorite scorpions managed to squeeze out of its box and disappear. "I knew it was in the Museum," Gray explained later, "since it was born and raised here." One day about three weeks later, someone burst into her office and said that a scorpion was loose in the crowded exhibition, causing panic. Gray rushed to the scene and found a large crowd gathered around the insect, which sat in the middle of the exhibit, stinger raised in fear. Several burly men had taken off their shoes to crush the insect, but they just couldn't work up the courage. Gray forced her way through the crowd, clucking disapprovingly, and picked up the scorpion in her bare hands. She is reported to have said, "There you are, I've been looking for you for weeks!" Then she turned to the crowd, dangling the insect by its stinger. "It can't hurt you," she explained, "if you pick it up by the stinger."
Gray's collection is periodically augmented by gifts from visitors. Several summers ago, she added two praying mantises to her collection: one picked up on the forty-fifth floor of the Empire State Building, the other discovered on a window ledge on the thirty-eighth floor of a Wall Street office building. Apparently, Gray surmises, the hapless insects were caught in updrafts of air from the hot city streets.
Gray recalled one of her strangest cases, that of a large grasshopper found on the observation deck of the Empire State Building. Gray recognized it as a species that could be found only in the South. The story was published in a newspaper, and eventually a woman came forward to solve the mystery. She worked as a secretary in the building, she said, and had received a box in the mail from a friend in Florida. Upon opening the box the grasshopper had popped out, and before the horrified woman could recover her wits the insect had escaped out the window. Normally this grasshopper inhabits the tops of rushes, and it instinctively climbs upward when confused. Thus, mistaking the Empire State Building for a lovely tall rush, the poor insect climbed several dozen stories to end up on the observation deck.
The Museum's only Insect Hall closed in the early 1970s. The remains of it can be seen in a storage area outside Gray's office—a series of dusty dioramas and various aging wax models. There are plans to create a new Insect Hall, but it may be years before it opens. According to entomologist and Deputy Director Jerome Rozen, it could include live material—like the Smithsonian's Insect Zoo—or just models. But live insects are expensive to maintain, and models expensive to build. Someday, though, insects are sure to take their proper place in the Museum. "The Museum," said Rozen, "simply can't neglect nine-tenths of the animal kingdom in its exhibits forever."
THIRTEEN
Amphibians and Reptiles
The Herpetology Department is tucked away, apart from most of the other offices, in a warren of rooms off the Museum's second floor. A sign on the department's main door discreetly points out that the offices are not open to the public.
One of the most interesting areas of the department is the office of its chairman, Dr. Charles Myers, which usually echoes with the sounds of chirping frogs. Along the walls are several terraria full of brilliantly colored and actively hopping frogs. Myers' research focuses on a group of animals popularly named poison-dart frogs—so called because Indians in northwestern South America use the frogs' skin secretions to poison blowgun darts. So far, Myers and his collaborators at the National Institutes of Health have discovered a dozen new species of these frogs—one of which is in fact so poisonous that it produces one of the most toxic nonprotein substances known to man. Appropriately, the vivarium containing this most poisonous and most beautiful of species—a brilliant golden yellow creature—includes a moss-covered human skull.*43
Myers and colleagues discovered this new species in western Colombia in the early 1970s. Two other poisonous species were previously known to be in this area, and a few writers had commented on the use of the frogs by the Indian population for poisoning darts. The poisoning method involved catching the frogs in the forest and bringing them back to camp. To obtain the maximum amount of poison, one witness reported, the Indians impaled the unfortunate animal on a sharp stick passed through the throat and out one leg. The dying frog might even be held close to a fire. This torture caused the frog to "sweat" the poison in large quantities off its back, and the Indians collected this secretion for their darts.
The new species of yellow frog that Myers discovered turned out to be twenty times more poisonous than its relatives—so toxic that Indians poison their darts simply by wiping the points across the animal's back. No torturing of the frog was necessary. "We didn't realize just how poisonous this frog was:' Myers explains, "until our contaminated garbage killed a chicken and a dog." Back in the United States, the scientists named the new species Phyllobates terribilis—for obvious reasons—and the toxin, when analyzed at the National Institutes of Health, was found to contain large quantities of a recently discovered class of compounds labeled batrachotoxins, or "frog poisons." Poisoning by these alkaloids swiftly results in blurred vision, convulsions, gagging, muscle rigidity, heart failure, and death. The skin secretions of a single frog may in fact contain two dozen different poisonous compounds, and there are no known antidotes. So far, over two hundred previously unknown compounds have been identified from the group of poison-dart frogs.
"In the rain forest," says Myers, "there could be over a hundred possible predators of frogs—snakes, birds, opossums, you name it. But most animals learn to avoid this frog very quickly. A snake, for example, will take one bite, drop the frog immediately, and go into convulsions. The snake usually doesn't die, so it learns to avoid the frog in the future." There is, however, one species of snake, Myers has discovered, that seems to be almost completely immune to the poison. Myers fed a young frog to the snake, which ate it without apparent ill effects. When he gave the snake a larger frog, it chewed on it awhile but couldn't swallow it. "The snake went limp and I could hang it over my finger like a piece of spaghetti, but twelve hours later it seemed fine. It just proves that nothing is immune from predation. But this frog comes close."
Myers is working on a related group which shows other intriguing problems. For example, a given species may come in hundreds of different colors, patterns, and sizes. Why a single species would show such tremendous variation is a mystery that Myers is still working on. "This could shed light on some fundamental problems in speciation—how species occur—as well as problems in genetic variation:' Myers explains.
The Herpetology Department employs two other curators and two scientific assistants. One curator, Charles J. Cole, keeps a colony of live parthenogenetic lizards in the department. These unisexual lizards (of which there are about thirty species) live in all-female populations that reproduce without the benefit of males. The egg of this lizard develops unfertilized, and the resulting offspring is an exact genetic copy of its parent. Among other things, Cole is trying to discover how these lizards evolved.
In addition to their research, these curators of the Herpetology
Department (like all of the Museum's curators) are in charge of caring for the collections and the planning of exhibits. The collection itself dates back to well before the Museum was founded.
On May 17, 1832, Prince Alexander Philipp Maximilian of Wied-Neuwied set sail for America with a Swiss artist, Karl Bodmer, on a grand expedition to explore the West. For thirteen months the prince and his companion traveled up the Missouri River, from St. Louis to the Rockies, through five thousand miles of largely unknown territory. Along the way, the prince kept his celebrated journal (which swelled to 500,000 words), while Bodmer created his splendid watercolors of the Indians and landscapes. A lesser-known accomplishment of their travels was the collection of jars and jars of pickled animals, including strange new species of snakes, lizards, and frogs.