LITMIR.BIZ

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male being in musth, and in that case she may be exercising choice.

      Mike Schmidt is impatient with these claims. “This is a problem in working with exotic animals in the field, and even in zoos,” he told me. “For some reason, people think they can get away with a lesser test of the validity of what they’re doing. If you have a theory stating that musth is rut, then you should have data that are in agreement with the theory—you should be able to demonstrate that all the bulls you are studying come into musth at the same time, because that’s what a rut is. It’s a seasonal thing. All the females will come into heat at that time, too.” Seated behind his desk, thinning hair neatly combed, his lab coat freshly pressed, Schmidt seemed the picture of reason. On a cupboard door behind him hung a calendar tracking the estrous cycles of the cows (“Pet OV, Hanako OV”)—a random overlay of sixteen-week periods. “We know that isn’t true of Asians,” he went on. “The females have independent cycles. They give birth all through the year—that’s been observed in both species, in the wild. So musth is not a rut. It’s primarily a phenomenon of aggression. When bulls are in the depths of musth, they’re absolutely incapable of breeding. We see a decline in the quality of the sperm late in musth. Now, that is certainly contrary to rut. They physically cannot bring normal mating to successful completion. They’re dopey, they’re somnolent. They may develop an erection, but they’re unable to control it.”

      The temporal-gland secretion itself is fairly complex, with twenty major components in a changing ratio. “The gland is a chemical-communication gland, and it may also function as a means of excreting testosterone,” says Dr. Lois Rasmussen, a biochemist with a Ph.D. in neurochemistry who is working with the Washington Park elephants. “It may be multifunctional.” Dr. Rasmussen is Lois on academic papers, and Betsey or Bets face to face. For the past eight years, she has been searching for the elephant sex pheromone, that odd thing that tells Packy or Tunga when Pet or Hanako is ovulating, the occult substance that Mike Schmidt measures in his sniff tests. Bets Rasmussen looks less like a biochemist than a high-school physical-education coach. Thin and wiry, with close-cropped sun-bleached hair, she is also an avid scuba diver and wildlife photographer, and her skin is tanned a nut brown from long spells under the equatorial sun. In addition to her pheromone work, she is deeply interested in musth, and has collected references to it from all periods of recorded history. Even a prehistoric cave drawing of a mammoth shows the dark streaks of temporal-gland secretion.

      “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

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