LITMIR.BIZ

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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.

      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.

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