“He said, ‘You know, I’ve got this really interesting problem I’m working on. I’ve done a lot of work on elephant behavior and elephant reproduction. But I’ve always been interested in chemical communication.’ This was a new term to me. So he started to tell me his ideas about temporal-gland secretion.” She and Buss collaborated on the first analysis of the secretion. In 1979, the Rasmussens moved to Portland, where Bets’s husband had an offer to work and teach at the Oregon Graduate Center. Bets received a faculty appointment without salary, giving her access to laboratories but no teaching duties. She was still principally occupied with fish, but as a last favor to Buss she visited the Washington Park Zoo and the elephants.
“The elephant keepers started to talk to me,” she recalled, “and I said, ‘You know, I’m really interested in this musth thing.’ I got to like the elephant people, got to know them, and one day I met Dr. Schmidt.” One of the first things Schmidt told her concerned the sniff tests and his suspicion that a pheromone was present in the urine. “I thought it was the most fascinating thing I’d ever heard in my whole life. Here was a problem that made everything I was doing with fish look like routine clinical chemistry.”
She went to the chairman of the Chemistry Department at the Center, an organic chemist named G. Doyle Daves, and repeated what Schmidt had told her. Together, they began studying the urine of elephant cows in estrus, Daves doing the laboratory work of extracting compounds from the urine and Rasmussen the biological checks, recording the urine-testing reaction of the bulls to the laboratory samples. Their timing was based on Schmidt’s blood data, and the keepers took responsibility for collecting the urine.
Urine collection changed the routine at the zoo in a permanent way. Whenever the designated cow of the day began to urinate, one of the keepers had to grab a bucket and race to catch the splattering stream. (There was no telling when this might occur. “Elephants can cross their legs till their eyeballs float,” Roger Henneous says.) The keepers were lucky to collect twenty liters from a cow in her fertile period; Bets, admitting to a chronic fear of running out of elephant urine, still keeps gallons of it in her freezers at the Center.
A few months into the work of chemical extraction, Daves left the Center for Lehigh University, and Bets was alone, without funding. “I was absolutely devastated,” she told me. “I was not trained as an organic chemist. I was a biochemist, which is very different. I had no choice—if I didn’t do the lab work myself I’d have to drop the project.” She began borrowing equipment and teaching herself to use it; she has since learned to repair it as well.
One of the central questions in pheromone research is that of transportation: how does the chemical signal move from, say, the female to the male, and how does the male perceive it? Most of the identified insect pheromones are dissipated on the wind in gaseous form. But mammals appear to have a more elaborate, intimate method. It is common, even daily, practice among mammal species for a male to check a female’s secretion by sniffing and licking her urine, her genital mucus, and her saliva. Often a female will assist in the process by standing still, moving her tail, or even politely urinating a small amount nearby. The male accomplishes his testing in a very specific way, by a behavior known as flehmen. Classic flehmen is a grimace—an expression of bared teeth, curled upper lip, and open mouth. Both sexes of moose, giraffes, cattle, sheep, and goats, seeking information not only about fertility but also about status and identity, demonstrate classic flehmen. The curious expression, with its appearance of casual disdain, is thought to bring, by tongue and nostril movements, a bit of pheromone into the vomeronasal organ, a chemosensor present in almost every mammalian species and also in reptiles. (It is vestigial in human beings, with anatomical remnants visible in skull sections.) The vomeronasal organ is distinct from the olfactory system and is separately connected to the brain; in snakes, in fact, it is more highly developed than the sense of smell. (Eric Albone, a chemist at Bristol University, in England, thinks that tongue-flicking in snakes may be a kind of flehmen.) When a male flehmens a fertile female, he “tastes” her fertility with his vomeronasal organ. The taste stimulates him into mating; once the female has become pregnant, or has ceased to be fertile, she tastes different, and he will leave her alone.
It had been known for a long time that elephants had a vomeronasal organ, but little attention and less research had been devoted to it. When an elephant opens its mouth, pressing the trunk above the head and revealing its tunnel-like throat, two duct openings are visible in the roof of the mouth. Bets Rasmussen was able to get a good photograph of these pits when she noticed Packy out in the yard trying to pull down the rain gutter of the barn. She waited until he stretched his trunk to its limit, and then she snapped the picture; it was the first ever published of the duct openings.
The elephant’s trunk, which is about eight feet long in a mature bull, has an astonishing number of uses. With its trunk, an elephant eats (hay, cigarette butts, a single ice cube, a half-dozen large carrots at once); sucks up water, as much as four liters at a time, and squirts it down its throat; digs, pulls up plants, or pulls down tree branches; fights; smells (an elephant can detect odors several miles away); bathes and dusts itself; caresses its kin. Elephants put their trunks in each other’s mouths, and sometimes an elephant drapes its trunk over a tusk, as artlessly as a man drapes a suit coat over his arm. The elephant rubs its own eyes, scratches behind its ears, and snorkels while swimming. (They are strong swimmers.) Elephants also flehmen; this is what is happening when a bull checks a cow in a sniff test. But a clear understanding of the nature of the behavior was a long time in coming.
“Everyone knew that the males stuck their trunk tips in the female urine, but they didn’t connect that behavior with the vomeronasal organ,” Bets told me early one morning as we stood behind the fence overlooking the back elephant yard. This is her spot—a corner of dirt and scrub not far from a head-high pile of elephant manure, which was steaming in the spring fog. Here she has bioassayed over ten thousand samples of urine extractions, in every kind of weather, standing for hours at a time as a lone bull paces the sand. We were watching Tunga, who is normally a slow, rather dull animal. But today he was in the early stages of musth and restless; as soon as he spied us, he trotted over to the moat and stood opposite us, swaying from side to side, foot to foot. “That’s one mad bull,” Bets said, laughing. Tunga seemed to roll his head in indignation, and suddenly we were sprayed with wet sand, stinging and sharp.
Before Tunga was released into the yard, Bets had splashed six different samples along the newly washed concrete apron. One was a control—fresh urine from a cow who was not in estrus. The rest were new extractions. In the lab one day, she had shown me fifteen small flasks of liquid from the extraction process, each a different tint and with a different odor. She pulled the cork for No. 1, and I smelled a startlingly strong urine with a lingering, bitter reek. No. 15, the last in the line, was a very light coral color, with an aroma of cinnamon. Nos. 4, 5, and 6 were straw-colored and had the most surprising smell of all: elephants and hay. She laughed at my expression. “When I first smelled those, I was sure I’d found the pheromone,” she said.
If a bull fails to respond to a particular sample, Bets doesn’t know whether that means that the pheromone is not present or just that it is present in too small a quantity. On the other hand, if a bull responds with unusual vigor she has to steel herself against untoward optimism. “As you separate these compounds, you create novel substances,” she told me. “The animal will often respond to them the first and second, and even the third, time you bioassay, simply because they are novel.” Six years ago, she found a volatile long-chain hydrocarbon. It felt, she says, like a pheromone. It was a common chemical, available in quantity, and she bought a batch of it. “We got tremendous response. We had five or six flehmens in a row from the bull. We thought we had found the pheromone! We were all elated. The next day, there was a response, but it was less marked. The third day, there w
as virtually nothing. The fourth, no response. That’s a pitfall in the work of others—they’ve only done their experiments a couple of times and then assumed they’ve found an active compound. So it was a valuable lesson.”
Tunga paced the concrete apron, sniffing the air. Suddenly, his trunk straightened like an arrow; the single fingertip at the trunk’s end flared, and he placed his nostrils flat against the wet surface. His jaw dropped open, and he held perfectly still for a moment, a sculpture of discovery and concentration. Then he deftly curled his trunk in upon itself, in a long and pretty oval, and pressed the tip against the two dark pits inside.
“Oh, that’s a good one,” Bets said. “I was a little worried about that sample.” The extracts that pass the test are further purified in the lab and then sent to Dr. Terry Lee, a longtime colleague of Bets, who gauges their molecular weight using a mass spectrometer. Bets made a check on her clipboard, looking down only for an instant, and returned to watching Tunga. “I get so excited about this part of the work sometimes that I dream about it,” she said. “I wake up and think, Gee, maybe tomorrow I’ll get a flehmen on that particular peak.” (She tends to refer to the samples as peaks, because this is how the various molecules show up in chromatographic analysis.) “The research wouldn’t interest me half as much if I couldn’t see the elephant do the flehmen.”
Bets has become something of a connoisseur of flehmen, with an aesthetic appreciation of the different styles. Tunga, she told me, will shake his trunk to “clear his palate” between samples. The idea of elephant flehmen was for a long time unacceptable to many conservative biologists; they considered true flehmen a behavior limited to hoofed mammals, and possibly cats. Most mammalian species are now thought to exhibit some form of flehmen, but one reason it took so long for elephant flehmen to be recognized is the trunk. No other animal has one, so there are no analogies. Another reason is the speed of the gesture; while Tunga has a leisurely approach, Packy is fast—his trunk whips in and out of his mouth in a few seconds. Bets was immediately able to see the gesture for what it was because she was looking for a pheromone. She believed, because of the results of Schmidt’s original sniff testing, that a pheromone had to be there. In turn, pheromone presence suggested flehmen, and so did a vomeronasal organ. In late 1981, after she became certain of the flehmen, and was able to obtain a series of photographs of the behavior, she submitted an article to Science. At first, she received what she refers to as a “scathing” review by the journal’s referees. I was heavily criticized for having used only two bulls,” she said. “I just drew on my knowledge of the literature and fought back.” In July of 1982, the article was published, as a cover story, but the idea was not widely accepted for several years.
There is a constant interplay between olfaction—smelling the urine and, perhaps, the pheromone—and the perception based in the vomeronasal organ. (Eric Albone points out that we have no word for that perception.) But in the tiny concentrations used in the bioassays there is so little urine left that no noticeable odor remains. The perception is thought to be occurring entirely within the vomeronasal organ, long a mysterious place. In 1983, Bets had an opportunity to study one when Mike Schmidt made the difficult decision to euthanize Tuy Hoa, the Vietnamese gift of gratitude. Tuy Hoa had congenital skeletal problems and suffered from severe arthritic and foot pains. The zoo’s only previous adult death had been Thonglaw’s, and he had been buried, with enormous trouble, in an isolated spot on the grounds. (“The problem with a dead elephant is that you don’t have the time for an autopsy which you might have with, say, a monkey,” Schmidt told me. “You have ten thousand pounds of decaying flesh to deal with, and in a zoo any death is a very unpleasant situation, which everyone wants to get through as soon as possible.” Tuy Hoa was “disarticulated” with chain saws and incinerated after an expeditious autopsy. Bets took Tuy Hoa’s head and attempted to remove the vomeronasal organ, a cigar-shaped white tube about a foot long and tightly bound in the middle of the skull above the soft palate. She was only partly successful. A few years later, a circus elephant died suddenly in Portland, and again she managed to obtain the skull. She worked through the night in a cold-storage room, and in about eight hours had removed the vomeronasal organ almost intact. She began to prepare a paper with anatomical drawings. This past summer, a colleague in Africa sent her the organ of a fetal African elephant, and she was able to work up comparisons. But questions remained. She was uncertain about how the organ connected to the nerves and glands, and exactly how it sat within the bone. Then there was another death in the Washington Park herd, when Susie apparently suffered a reaction to a routine drug.
“I’d just walked in the door from a trip,” Bets recalled. “I was exhausted, and the phone rang. It was an opportunity I couldn’t turn down, because there were probably five major questions I still had about the anatomy. With the circus elephant, my major objective had been to get as much of the organ out as quickly as I could, so that I could accurately determine the histology and cytology. Once I learned that Susie had been dead for four or five hours, I knew there was no point in looking for that. The thing to concentrate on was the anatomy. We can only speculate, on the basis of what we know from other animals, about what happens on the receptive side of the vomeronasal organ. You can’t put a compound labeled with a fluorescein dye there and let the animal flehmen and then cut the skull apart to see how far up the vomeronasal organ the dye went. You can’t do electrophysiological tests, so you can’t know the response of the bipolar neurons inside the organ.”
She could, however, map the anatomy. “I spent five days on Susie’s skull, usually about eight hours a day,” she said. “I went very, very slowly. The most fascinating thing is the enormous size of the sinuses. The elephant brain is back behind the ears, in line with the eyes, and all the stuff above that is sinus—incredibly honeycombed pockets. I dissected part of the skull with fine dissecting tools—the kind a neurosurgeon uses. In many places, I had to go through four inches of bone with a metal cutter. Then I would take photographs, and label the whole thing along the way.”
She is not, however, immune to loss. The dissections were a strain. “I had to cut Tuy Hoa’s trunk off. I’ll never forget that. She had been dead three hours, but it felt as if I were killing her. With Susie, the eyes were there. Someone came and took the eyeballs out—I never could have done that. I would find it impossible to dissect Sunshine. I’d just say, ‘Forget it.’ But I guess if the guys are cutting them up for disposal, then I should be there getting the information, and I can’t afford to be sentimental. If it was hard for me, it must have been really hard for Roger and Jay and Jim. I firmly believe in my own research. If I didn’t believe in it, I would have quit about five years ago, because the last three or four years have been slow going. I can’t believe I’ve been working so many years on this. That’s one thing about working with elephants—you learn patience.”
THE FECUNDITY OF the herd at the Washington Park Zoo masks the pressure on elephants in the wild, and captive breeding may be, as Mike Schmidt calls it, “the last hurrah” of Proboscidea. Schmidt continues to occupy himself with the ovulation cycle, but for several years he has taken his research in a particular direction—that of artificial insemination. The survival of the species can’t be assured, he feels, by successful breeding in one herd, or even in several. The genetic pool is painfully small; he estimates that in the United States at this time there are 326 Asian cows and eighteen Asian bulls. And the Endangered Species Act has, since 1976, made the importation of Asian elephants virtually impossible.
“Artificial insemination is the best way to ensure the genetic variability of domestic elephants,” he told me. “And it will also have implications for managing wild elephants. If you have a population of no more than five hundred elephants, they will sooner or later become extinct—though that sounds like a lot of elephants—because there’s not enough genetic diversity. But if you take just six other animals every twenty years and inject th
em into that population it can go on forever. Where are you going to get those six unrelated animals? You’re going to get them from your domesticated herds. But there are problems with A.I. in the case of elephants. If your timing is off, you’ve got a four-month wait. And elephant anatomy makes it difficult—you have to go four feet to get to the cervix. The route is circuitous—up, over, and down—and requires flexible fiber-optic tubing. Managing that and preserving the sperm adequately are going to take years and years of work.”
Several months earlier, Schmidt had travelled to Thailand for a conference on elephant preservation and presented some of his research on artificial insemination. Another of his goals, he said, had been to persuade Asian elephant handlers to encourage their working bulls to breed. “I’m eager to collaborate with the Asians, because they have the numbers of animals,” he told me. “Almost everything we’ve done, from the beginning, has been geared to practical application in the field. You could develop a terrific research method for inseminating elephants using stereomicroscopes and manipulation of embryos, or something, but so what? There might be only three places in the world that could do it. So how can we take the knowledge and turn it into a practical method to use on thousands of elephants? We can’t save the Asian elephant single-handedly, even by building a monster zoo in America.”
There is one profound problem to solve if artificial insemination does succeed, and that—once again—is musth. “Suppose A. I. is gloriously successful and you’ve got all these pregnant cows,” Schmidt said. “Half the calves are going to be males. In ten years, most of them are going to be shot. It’s not responsible to get into that situation—you have to have some way of dealing with surplus males. Some will be kept for breeding, but what are you going to do with the rest? Well, you can castrate them. They can be work elephants, they can be exhibit elephants. What about a little zoo in the Midwest with one elephant—an Asian cow that’s never going to be bred? She should be in a social group, yet they’ve got room for only one elephant, and, in any case, they can’t afford a group of cows. Well, they could have a neutered male instead—he’s going to be a docile animal, easygoing, happy-go-lucky, imprinted on people. He doesn’t need to be with other elephants, or to breed, to be happy.”
Violation Page 7
