Violation (8 page)

“It's important to note that there are two species of elephants, in separate genera,” she told me one hot afternoon last August. We were sitting, shoulder to shoulder, in her tiny office at the Oregon Graduate Center, a private research institute outside Portland. The walls were covered with posters and photographs of elephants—elephants mating, elephants walking, fetal elephants, elephants in various stages of dissection. “In one of these species—the Asian—musth has been recognized for hundreds and hundreds of years. In the other species, there has been some recent evidence of a musth-like phenomenon. But you can't conclude that the two are the same, because the evidence is only starting to be gathered. You don't just take a term out of the dictionary and plug it in somewhere else.” The first false assumption is that musth is
a rut, she says, and the second is the application of that term to another species.

“Now, my experience is with Asians,” she continued. “If these two states are the same thing, we should see the same behavior in both species, and we don't. If I take urine at certain times in the musth cycle, and make an extract, I get several reactions from the cows. There's an intense reaction at first—the cow checks the spot out. After that, there's an avoidance. Such data are not consistent with a cow's being attracted to a male, or signaling that she's getting ready to go into estrus. I remember watching Hugo in the viewing room when he was in very heavy musth. He was dribbling urine. We let him out and let the cows in, one by one. The first one in was Pet. Normally, she strolls around while she's waiting for the others to come in. This time, she stopped dead, and she seemed—well, it's anthropomorphizing, but she looked nervous, timid. She went around the room practically on tiptoe. Okay, in the early days of the attempts at breeding the elephants she was bred several times to Hugo when he was well into musth, and he tends not to breed then but to beat up the cows. He almost killed her one day. So she remembers the smell of that musth urine—which does smell horrible. Males avoid each other in musth. Cows avoid musth bulls, too. If cows are afraid of a musth bull, then how is musth a rut? It doesn't make sense. Musth is
not
a rut.”

THE STUDY OF
pheromones is a new one, as scientific studies go. The name wasn't invented until 1959, and then only after considerable argument. The roots of the word are Greek for “carry” and “excite”—a good term for the myriad roles of these substances. Pheromones are chemicals used for communication among individuals of a single species. They are secreted as liquids and usually received as volatiles, and they constitute a conversation of sorts. Slime molds, algae, and fungi all use pheromones. Social insects, such as ants and bees, may use a dozen or more pheromones in a typical day—one to raise an alarm, another to mark a trail or a particular plant, another to signal social status or group
membership. Barnacles collect on rocks and boats by following pheromone signals. When a honeybee stings, it releases a chemical that alarms nearby honeybees.

Pheromones are also used in combination. Research on the Oriental fruit moth shows that not just one chemical but five must be present in a critical ratio in order to attract a male. There are releaser pheromones, which (like the honeybee sting) cause rapid behavioral responses, and primer pheromones, which affect physiology and trigger developmental changes; the most famous example of these is the pheromone that enables a queen bee to suppress ovarian development in worker bees. One of the most dramatic characteristics of pheromones is what the sociobiologist E. O. Wilson calls their “efficiency”: they are among the most potent biologically active chemicals known, able to transmit complex information in tiny amounts over long distances for long periods. The Texas leaf-cutting ant, for instance, can point the way to food by leaving a trail some hundred yards long, which can be found and followed for months. The extreme dilution of the chemicals makes their identification exceedingly tedious for the researcher. The silkworm moth responds to only a few molecules of a certain chemical; hundreds of thousands of moths are needed to produce ten milligrams. Two hundred thousand fire ants must be sacrificed to collect a quarter of a milligram of a pheromone. Furthermore, many of the pheromones isolated so far have been new compounds.

Mammalian pheromones have proved much more difficult to identify than insect pheromones. Among mammals, pheromones have been clearly identified only in male pigs, in female marmosets and springboks, and in both male and female guinea pigs, hamsters, and mice—though it is thought that all mammals (with the possible exception of human beings) use them. In every species, it is the sex pheromones—with all they imply about behavior and free will, and the potential for use in husbandry—that are of the most interest. The typical exchange involves chemicals used by the female to attract the male; occasionally, the male
will draw the female. Another insect example is that of an arrestant chemical found in certain mites and mosquitoes: it calls the male to an immature female and forces him to attend her until she is ready to mate. Pheromones exert a disturbing amount of control, fostering attraction, repulsion, a willingness to wait, to consort, to surrender. I was delighted when I first read of the male pig's pheromone: his salivary glands secrete a steroid related to testosterone, and when he spits in a sow's face she immediately takes up a spread-leg position, ripe for the taking. (This same steroid, it happens, is found in truffles.) But, being a mammal myself, the longer I considered the possibilities the more uncomfortable I became.

Much of what I know of pheromones I have learned from Bets Rasmussen. If she succeeds in isolating an elephant sex pheromone, it could be a turning point in the fight to restore and preserve the species. She talks of the possibility of chemical “fences” in the wild to attract elephants to preserves and hold them there, and of a stimulant to encourage breeding in zoos and facilitate sperm collection for artificial insemination. There is, too, she admits, the joy of solitary research: the voyage into the unknown and the delight of discovery. “Mammalian pheromones are just now being isolated,” she explained. “Substances that were identified as pheromones in some of the early work have turned out to be impurities. Mammals are more complicated organisms than insects, and they have pheromones doing a variety of things. Even if you're thinking just sex pheromones, you have to separate the mating process into its components: attraction, pre-copulatory behavior, actual copulation. There may be more than one pheromone acting at each stage.”

In 1976, Bets Rasmussen was raising two children while she did independent research on the interaction, in sharks and other primitive fish, of the brain and the cerebrospinal fluid. She lived in Pullman, Washington, where her husband, an atmospheric scientist, was teaching at Washington State University. In the lab one day, she met a biologist named Irven Buss, who was looking for an assistant.

“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.