Interviewed May 1994 by Shari Rudavsky

If five years ago you asked Margie Profet what she did, she would toss back her long blonde hair, laugh, and say in that breathless voice of hers, "Oh, I'm just being a bum." And if she'd told you what she really was doing--working part-time jobs in San Francisco but mostly hanging out, thinking, and reading in her apartment--you'd probably agree.

Two centuries ago, Profet, who holds bachelors degrees from both Harvard and Berkeley, would have been called a natural philosopher. But late-twentieth-century big-time science, with its supercolliders and genome projects, has little place for a natural philosopher. Yet Profet, with neither formal academic credentials nor a university position, has persevered, driven by her desire to know answers to one of the biggest questions: why humans evolved the way they have.

Her recent life sounds like a Cinderella story. Beginning in the mid Eighties, Profet practiced her solitary scholarship in a Berkeley studio modeled on a medieval garret complete with stucco fireplace and heavy wooden ceiling beams. A cadre of squirrels and scrub jays roamed the apartment with impunity, seeking the peanuts she kept ready, as Profet troubled out evolutionary explanations for such riddles in human physiology as why women menstruate and how allergies have affected our survival. Then last spring, her prince arrived in the form of a $250,000 MacArthur grant that finally freed the 35-year-old researcher to devote herself entirely to some of the most daring and useful thinking in evolutionary biology today

Profet focuses on three areas of evolutionary physiology, all with powerful clinical applications. Her first work, proposing that pregnancy sickness prevents mothers from eating foods that might damage their fetuses, has steadily gained acceptance in the medical community. An early article explores how allergies shield us from toxins in plants and venoms. Recently, she gained national attention by suggesting menstruation serves to cleanse the uterine walls of sperm-born pathogens.

Deep into the books and papers of evolutionary biology but lacking any formal training in it, Profet one day found herself listening to several pregnant relatives gripe about morning sickness. She asked herself, Did pregnant women of the Pleistocene avoid certain foods that brought on nausea? "Pregnancy sickness was curious," Profet recalls thinking. "It only lasted for a while but was strong. The food made them sick, so it must have some bad things in it. I started to think about whether it made sense, just for fun."

Insight does not equal proof, so Profet spent months buttressing theory with extensive research into the literature. Her arguments were so persuasive that a leading journal in the field published her paper. A recent article constituted the greater part of last September's issue of the Quarterly Review of Biology.

As a child growing up in the suburban aerospace community of Manhattan Beach, California, she saw little appeal in the so-called normal lifestyle. "I remember looking at people going to the office every day and housewives doing this and that, and thinking at age 7, Life is really boring," says Profet, the child of a physicist father and engineer mother. Life grew more interesting when she entered Harvard and majored in political philosophy. "My brain grew a lot. When you're working hard at philosophy, you take ideas that on the surface don't seem connected and go a level deeper," she says. While spending two years in Germany working as a computer programmer, she began to see that political philosophy had no answers for questions that intrigued her. Despite a distaste for regimented learning, she returned to school, this time to Berkeley, to study physics. But physics also couldn't satisfy her lust to know why.

She decided to just think, supporting herself with a string of part-time jobs, "Even with my Harvard degree and physics degree, people would be really insulted when I applied for jobs because I was different," she remembers. Eventually, toxicologist Bruce Ames [OMNI interview, February 1991], whom she says "collects eccentrics," read her allergy paper and offered her a part-time research job in hislab.

A few months after getting the MacArthur, Profet gave herself a sabbatical, leaving behind her squirrels and sliver view of the bay. Now in Seattle, she continues her work on allergies and is converting her re-search on pregnancy sickness into a book, Protecting Your Embryo. Interviewer Shari Rudavsky first visited Profet shortly before she moved. As the tame squirrels interrupted periodically to agitate for peanuts, Profet shared her provocative thoughts on science, medicine, and academe.

OMNI

Your work seems to depict the body as engaged in a constant battle with toxins and pathogens in the environment.

Profet

Well, parts of the body. We're in a co-evolutionary race with a zillion organisms out there. Bacteria and viruses want to exploit us the way we exploit other animals. We eat plants, animals, and kill our neighbors. So an awful lot of what our body does is geared toward defense against other organisms. Some defenses haven't been appreciated as such. These anomalies in particular, macroscopic enough that anyone can see them, interest me. These mysteries are there for a reason. Where you can look at what's going on, it's too intricate not to be adaptation.

As an evolutionary biologist I'm acutely aware that we're in a coevolutionary race with everything else. That's my fundamental way of looking at the world. The function of the nose is to smell things, but this food often doesn't want to be eaten. You're smelling out a potential predator or conspecific that may want to steal your mate, so the nose also works as your defense.

OMNI

Allergies, you write, evolved as a last defense against environmental toxins. How do allergens and toxins differ?

Profet

The allergen--the molecule your immune system actually targets--may be a tiny toxin or a much larger protein commonly associated with it. Compared to a toxin, the protein's a big target for the immune system. Say somebody eats a peanut at age 10 and suddenly becomes allergic to peanuts; this allergy was probably caused by a toxin, either a natural peanut toxin or one from a mold that had infected the peanut. Your immune system says, "Aha, a toxin! And this protein is associated with that toxin. No more of that protein." Because it's a better target, that protein is now an allergen.

OMNI

What inspired you to look at allergies?

Profet

I have a lot of allergies to shampoos and soaps. Lying in bed late one night scratching, I thought, What the hell is this for? I knew allergies were caused by this one highly specialized class of antibody, so they must have a function. Well, what are the symptoms of an allergy? You're either scratching something off, vomiting, having diarrhea, tearing, sneezing, or coughing. It seems you're trying to expel something immediately, not three days later, like a bacterial infection or virus. What is so immediately dangerous that you have this dangerous mechanism which can lead to anaphylactic shock? Viruses and bacteria give you these reactions only if you've got food poisoning. I wondered if allergies evolved to protect against toxins.

OMNI

Why do people show such capriciousness, or variety, in the kinds of things they're allergic to?

Profet

Our different genetic compositions give us very different sets of enzymes. Because of our different life histories, you and I also have different levels of enzymes induced. Enzymes break down toxins, rendering them nontoxic and excretable. If you lack sufficient enzymes for a particular kind of toxin and it's an irreversibly binding toxin, it keeps circulating in your bloodstream and you'll probably develop an allergy to that toxin. It depends on the quality and type of toxin, which enzymes you have and don't have, the inducibility of your enzyme systems, and your genetics.

OMNI

How does your theory stack up against the competing helminth hypothesis? [The helminth hypothesis, or "little worm theory," suggests the immunoglobulin E (IgE) response originally evolved as a coping mechanism against parasites. In our society where parasite loads have lessened, IgE incorrectly targets other substances, leading to an allergic reaction.]

Profet

Unfortunately if you read a review article on the helminth hypothesis, you'll get glowing reports of all the evidence in support of it. But then you look at the primary literature and there's no evidence and much against it. If you're living in Gambia and have a filarial infection--little worms--you're actually much better off without a strong IgE response. People with strong IgE responses to filarial worms often have elephantiasis--an enlarged scrotum, enlarged thighs--or terrible chronic pulmonary disease. IgE levels have no correlation with a person's ability to expel these worms.

Now the thinking among some immunologists and parasitologists is: "Well, maybe IgE evolved to protect against helminths but doesn't now because these worms have gotten so sophisticated." The really dangerous part of this is that researchers now want to find a vaccine to induce a strong IgE response in people who have worms. They're going to kill people right and left if they do! And the people they'd be trying this out on will be Third World people with no legal recourse.

OMNI

Your theory contradicts the accepted immunological canon. Did you have problems getting people to consider that the standard thinking might be wrong?

Profet

The comments I got on my Quarterly Review of Biology paper represent what's wrong with much of the thinking. I put a sentence from one referee's comment next to my bookshelf to remind me never to become like that: "There is much greater acceptance in the immunological community of the idea that IgE-mediated responses have evolved to deal with parasitic infections. Thus, there is not the pressing need to find another reason for IgE." People still say things like that.

OMNI

Why do you think people are so attached to this hypothesis which you claim has "impeded parasitology for three decades"?

Profet

I can't figure it out. My forthcoming article argues that it's much more likely that the helminths are manipulating the IgE system for their own benefit. Look at the other things we get allergic to: venom, certain drugs, carcinogenic metals, foods, pollens--all are toxins or contain toxins. The helminth people just ignore this. They found a pathogen they've sometimes correlated with high IgE levels, and so they think IgE evolved to fight helminths. All the other cases of IgE they seem to think are just mistakes in the immune system. The common thinking is: "Long ago, we all had such heavy worm burdens that IgE's were kept busy doing what they were supposed to do. But now, we don't have a lot of worms, and so these IgE's are busy looking around for something else to do; they target incorrect molecules." [sighs] The thinking is so warped. If the body's IgE system must be permanently at war with worms in order to function properly, it must not be very good at expelling worms, because people have these infections for 20 years.

OMNI

Has your theory affected the way you deal with your allergies?

Profet

Definitely. I tend to find one thing I like and pig out on it for weeks and weeks--just what you're not supposed to do. You're supposed to diversify your diet. I love strawberries, so of course, May came along, and I ate two baskets at once, and of course there happened to be mold in them. I could taste it and spat some out, but I also swallowed some. The next time I had a whole basket, I became nauseated, and soon, with only one strawberry, I was out for a couple of hours.

OMNI

What about other allergies, such as from shampoos?

Profet

Oh boy, it affects what I buy. Even if there's no ingredient I'm specifically allergic to, I'm going to be predisposed to allergy. I have so many skin allergies. I stay far away from things with lots of plant oils. They generally have plant toxins. I have to use olive oil-based hand soap. I don't have respiratory allergies, so I'm lucky there.

OMNI

Why are chronic respiratory allergies so common today?

Profet

Historically, they appear fairly new. What precipitated this? People are too miserable. You can't live a normal life always being on antihistamines, sneezing, coughing, tearing, and itching all the time. There are certainly correlations with the number of particles in the air, but the main thing is the number of viral respiratory infections you get while young. In a hunter-gatherer society, you're probably in contact with a few hundred people your entire life. As a modern child going to daycare, by the time you're 6, you've had an average of 22 colds. That's not normal in an evolutionary sense. A child with so many infections may have a lot of temporary lung lesions, so it may be easier for a pollen toxin to get more deeply embedded and so trigger production of IgE. That's my guess.

OMNI

Allergies, then, would not be an example of your body's poor functioning, but of it's proper functioning?

Profet

Your mechanisms are being fully functional. You're being exposed to an abnormally chronic and high level of something and you're body's saying, no, get away. You're not, because instead of being a nomad who wanders from place to place or staying away from that one fruit because you know it akes you sick, you don't even know what ingredients are in the thing you're eating or in your shampoo because everything now has so many ingredients. If you want to keep living that lifestyle, you may have to find a way to suppress that alllergy. But you should know why that allergy occurs--is it really protecting you against a danger or is your IgE system overreacting.

OMNI

How would you suggest reducing allergies?

Profet

Breast-feeding. It's not a defense against allergies, but in a normal Pleistocene environment we breastfed for three or four years. The things you get in breast milk, such as the IgA antibody seem to prevent a lot of IgE binding to things. It's been suggested that if you take away breastfeeding and the IgA antibodies going into the baby, the baby's left with all these IgEs and may suddenly get a lot of allergies. Also diversify the child's diet.

OMNI

What are the implications for pharmaceutical research?

Profet

There are a lot, but I don't know what just yet. There has been some research into ways to completely suppress the allergy mechanism and I don't think that's a good idea except in life-threatening cases. You don't want to completely eliminate IgE as a mechanism, but you want to pinpoint what people are allergic to so that you can make enzymes to specifically degrade those things. Pharmaceutical companies are trying to either treat the symptom, prevent the symptom from occurring, or prevent that allergic response from getting started. And actually, that's worth doing.

OMNI

Are people without allergies at a disadvantage?

Profet

Somebody with the full capacity for allergies but has none is probably very healthy. But if you don't have capacity for allergies, or you have a very low capacity, then you may be in trouble.

OMNI

What was it that led you to link morning sickness to diet?

Profet

A lot of siblings and siblings-in-law were going through pregnancy sickness, and I started wondering whether Pleistocene women couldn't eat when pregnant. I read Marjorie Shostak's book Nisa, and one way a Kung-San woman knows she's pregnant is by a sudden dislike of foods and things tasting bad. Knowing it is basically confined to the first trimester, I wondered if various poisonous plants were especially likely to harm the little, rapidly differentiating embryo. I went on a detective hunt--looked at journals, books on plant toxins, pregnancy, organogenesis, teratogenesis, and discovered the online services. There are weird things in early pregnancy. People usually don't connect a sensitivity to smells to morning sickness but look on it as a bizarre byproduct of the hormones of pregnancy.

OMNI

Do most women get pregnancy sickness in the morning?

Profet

It's any time of day. Some women do mostly in the morning, some mostly at night; some have a constant level of nausea throughout the day. Generally, they have strong aversions to foods and odors whenever they come in contact with them. I think the area prostrema, the brainstem nucleus that samples the bloods for toxic constituents, becomes recalibrated in the first trimester so that almost any food or odor may trigger some nausea.

I think some women do get it in the morning because the digestive system slows considerably during the first trimester. A woman digesting her meal when she's asleep is digesting very slowly. Since sleep inhibits vomiting, when she wakes up, she just has to vomit. Also, since you're not urinating in the night or as frequently, you're not flushing as much stuff out. Women may get sick in the morning but have the aversions whenever.

OMNI

Why is the variability of this phenomenon so great?

Profet

Well, there's a question within that question: If this is an adaptation, why hasn't natural selection been more precise? Why has it allowed such variability? The answer may be that benefits conferred and costs are tied. The greater your degree of morning sickness, the greater protection your embryo will have. But the greater the protection, the greater your nutritional costs will be also. In extreme pregnancy disease, you can't eat anything; you throw everything up, and you die, so your benefits drop to zero. At the other end--having no morning sickness--the cost is zero, but the benefits are also zero. Your embryo is more likely to develop birth defects. Then there's this wide middle range where benefits and costs are going to trade off.

OMNI

What are the medical ramifications of pregnancy sickness?

Profet

Almost all pregnancy advice in popular books is geared toward second and third trimester. But because every major birth defect occurs in the first trimester, the priorities for the embryo are very different then. As it's forming limbs, heart, liver, eyes, the early embryo is most susceptible to damage by toxins. Its nutritional needs in terms of raw calories are slight. It weighs only a few ounces at the end of three months, not even that. The body's priority is getting from one cell to a perfectly formed three-month fetus. During the second and third trimesters, the fetus has its basic organs. While more susceptible than an adult, it's not terribly susceptible to toxins. At this time the fetus is growing rapidly, so the real priority is nutrition, protein, getting the calories. Look at the dietary advice that women get: Eat lots of broccoli. You should not eat lots of broccoli in the first trimester. Broccoli's got wonderful nutrients, but it's also got many natural toxins. The pregnant woman finds broccoli nauseating for good reason. You don't want to inflict those toxins on your developing embryo.

I get phone calls from all over the country. When women say they had no apparent pregnancy sickness whatsoever, I usually don't believe it and start grilling them. Could she eat Chinese food, certain spices? Usually they admit, "Oh, I did throw up on mushrooms once," or, "Okay, I threw up on coffee." After you interrogate them, you find out they really did have pregnancy sickness. But one women didn't, and she ate everything--onions, spices, all that stuff you shouldn't during the first trimester. Her baby was born with a suite of developmental defects. She called me because she was two weeks pregnant with her second child and wanted to know what to do to avoid inflicting toxins on her baby.

OMNI

How did you council her?

Profet

I said go bland. Nothing bitter, nothing pungent. Only the freshest meat and dairy products. You may want to cook the vegetables a lot to get out the toxins. No barbecued anything. Lots of ripe fruit, but avoid unripe fruit.

OMNI

Why do we need an evolutionary explanation for pregnancy sickness?

Profet

There are plenty of implications when you project a Pleistocene mechanism onto modern society. Pleistocene woman had pregnancy sickness that pretty effectively deterred her from eating toxins in her environment. She didn't need to know the purpose of morning sickness, but we do to consciously alter our behavior to avoid inflicting these things on our embryos. We're not in a natural environment; we're exposed to toxins that lack the cues of natural toxicity because we bypass the taste or smell receptors by swallowing or injecting them. Or they're an evolutionary novel, like alcohol, and we haven't developed mechanisms to protect the embryo against them. Take chocolate. Its bean is incredibly bitter, but we mask the bitterness with lots of sugar. That's the kind of thing you want to avoid during the first trimester.

Also, to ovulate, you need a threshold of fat or calories. You usually can't conceive a baby in famine conditions. To conceive, you've stored up vitamins from this diversity of vegetables and fruit. The liver can store four months worth of folic acid. A folic-acid-deficient woman has a greater risk of giving birth to a baby with neural tube defects. But if you routinely pig out at McDonald's, you're not getting sufficient levels of folic acid. You may be nutritionally depleted of certain things but still be able to conceive.

OMNI

Do we have an increased rate of birth defects from teratogens?

Profet

A lot of people are born with nongenetic developmental birth defects, and certain natural teratogens cause birth defects. In one famous case where the family goats were grazing on lupine, which is full of toxin, both the kids of a pregnant goat were born with crooked limbs. The woman gave birth to a boy with these limb defects, and a litter of puppies was born with this defect. And thalidomide is a terrible teratogen. Women took a tiny bit of that in pill form to mask the bitterness. If they took it within a 20-day or so time span when their babies' limbs were forming, the babies were missing limbs. Hamsters fed a high level of potatoes, which have high levels of toxins, sometimes come out with neural tube defects. Many naturally occurring plant toxins are known to cause horrible birth defects, but people haven't asked, "What are the thousand things you ate and was your baby born with birth defects?"

OMNI

Are there any cultures where women do not experience pregnancy sickness?

Profet

Other people believe there are; I don't at all. Human physiology is the same everywhere. Women in one culture may experience pregnancy sickness to a lesser degree if they're eating something that interferes with that mechanism. But I don't belive that mechanism is absent anywhere.

OMNI

[A squirrel comes in for food.] Does her diet change when she's pregnant?

Profet

She seems a little more persnickety when I think she's pregnant. When Peanut was a baby, she wouldn't touch roasted peanuts, but her mother would--like our babies don't like vegetables but learn to tolerate them. You don't want a kid out grazing on plants. You want them to learn which ones they tolerate without getting sick or dying. People learn to smell and taste gingerly like any mammal that eats a wide variety of vegetation. If a deer comes to a novel food source, it will eat the first bit so gently. If it doesn't get sick, it will come back and eat more.

OMNI

Will your theory have psychological and social impact?

Profet

Women have been blamed for pregnancy sickness. For much of this century, severe pregnancy sickness was considered an oral attempt at abortion--a loathing of femininity, your husband, or sexuality. Freud did not help matters. In the Thirties and Forties, physicians sometimes would isolate women who vomited excessively in early pregnancy from friends and family in hospital rooms and take away their vomiting tubs so they had to vomit on themselves and wallow in it. Even up-to-date books on pregnancy that discuss severe vomiting say, "Think about what it is in your pregnancy that you can't stomach." Many women with severe pregnancy sickness are treated in a very condescending fashion by their husbands or parenting partners, like, "Oh, this is in her head. She's not coping well with her pregnancy." Women are told they should feel lucky if they have almost no pregnancy sickness. Well, you weren't lucky if you didn't.

OMNI

When did you start working on menstruation?

Profet

When I was seven I learned I was to undergo this monthly bleeding. I was disgusted, not because of the blood, but by the design--that our bodies were so inefficient they couldn't do anything better with the blood, like absorb it. I never bought the explanation.

OMNI

In a Kekulelike statement, you credit a cat for inspiring your paper on menstruation by waking you up from a dream. What was that dream?

Profet

Gelato was a whiny, very smart cat. I loved this animal for some dumb reason. He'd always meow in the middle of the night to go out and hunt. He was so persistent; he always won. One night he woke me at 3:00 a.m. Earlier I'd had a conversation with my sister about variability in menstrual flow. Who knows why--you know, sisters talking. And I had a vision in my dream of a cartoon from grade school. The girls watched menstruation films and boys sports films. The boys were always so envious because we were learning the secrets of nature. The films' little images showed ovaries, the uterus: "During the month, the uterus builds up this nice lining. But if it doesn't get a fertilized egg, then it doesn't need that lining, and it just comes out as blood."

I saw the pale yellow ovaries and real red lining of the uterus, and the red was flowing out of the cervix. But there were all these tiny black triangles with pointy tips embedded in the uterus and they were coming out with the flow. As soon as Gelato woke me up, I knew the black triangles were pathogens. And I said, "Oh, so that's why," and went back to sleep. The next morning, puttering around the house, I thought, Didn't I have some weird dream last night? Then I thought, How would pathogens get up there; the only thing that gets up there is sperm. Maybe pathogens ride on, hitchhike on sperm. In my first literature search, I found tons of articles. This is not some obscure fact--it's blatantly out there. That's why I gave Gelato the acknowledgment.

OMNI

Do species other than humans menstruate?

Profet

Most books say it occurs only in humans and higher apes, no prosimians, nothing else. I suspect virtually all mammals menstruate. Mammals from many different orders have been shown to menstruate if you dissect them at the right times. They may reabsorb the blood or just a trickle comes out and is absorbed in their fur or hidden in their mucus. You do vaginal or cervical swabs or dissect them to find out. Go back to the nineteenth century when biologists picked their species and target organ and then dissected 130 of those, and you find all these studies where they dissected monkeys or tree shrews and find, yeah, they're menstruating, albeit "covertly." People were surprised, but covert menstruation is fundamentally the same mechanism as overt menstruation. The difference is in the amount of blood.

Humans probably have the most copious degree of menstruation, and we are the only species known to have ovulation that can't be detected except by modern technological methods. Since we have sex throughout the cycle, soon after menstruation, you're getting sperm up into the uterus and oviducts. Well, pathogens hop on and can replicate many times before the next menstrual cycle. The cervical mucus is most receptive to sperm during ovulation and least receptive post-ovulatory. But it's semireceptive early in the cycle because your estrogen is rising. So maybe you're getting pathogens up early in the cycle, three weeks before your next menstruation. That's a long time for bacteria to replicate. So in humans you'd expect a large degree of menstruation, whereas, depending on the species, wild animals generally copulate only during the few days or hours of the cycle in which the animals are in estrus.

OMNI

According to your theory, what kind of birth control should women use?

Profet

You often get a trade-off between blocking sperm and sexual fulfillment. Some men cannot get sexual pleasure wearing a condom; the same for some women with the diaphragm and spermicide. Many poor women are getting IUDs because it's simple, they don't have to remember; it's just stuck up there. But the problem with IUDs is when you insert it, you insert pathogens with it. Many IUDs have that tail hanging down that can be ascended by pathogens. The Dalkon shield acted like a wick and just sucked up pathogens. You're at a slightly higher risk with IUDs, but you're bleeding more and that helps to compensate. But for the duration, there's chronical injury to your uterus. Once the IUD is out, it goes back to normal. But if you look at the uterus taken out of a hysterectomy patient who had an IUD, there's the imprint of that IUD in the tissue. The IUD is achronic irritant to the uterus that causes inflammation, which is an indication of infection or potential infection. Components of the inflamatory response prevent pregnancy because they're toxic to the fertilized egg. But this inflammation is a cue that there's potential infection, so the uterus responds with heavy bleeding.

OMNI

How do menstrual cramps and PMS fit into your interpretation?

Profet

The uterus is always having minor contractions, because it's shedding the mucus through the vagina. Those contractions are more synchronized and stronger during menstruation. That's what is thought to cause the cramping. With PMS and severe cramping, it's hard to say. Hunter-gatherer women experience some anovulatory cycles in their early teens, then get pregnant, lactate for years and have no menstruation, have a few cycles, get pregnant again, and so on. Women in our society undergo many menstrual periods and so much hormone buildup. We're not aware of all the signals this chronic cycling tells the body. The body is saying, "Gee, is something wrong? She's gone through 82 cycles and she's not getting pregnant!" Does the body respond by increasing the number of receptors for different hormones because you're giving the body the message that you're not pregnant, and it's trying to change its parameters, recalibrate things? Some women today do get these dramatic premenstrual symptoms and terrible cramping, and we don't know how natural that is. In Nisa, Shostak talked about hunter-gatherer women getting some discomfort and premenstrual moodiness, but it did not see to be nearly as extensive as women here.

OMNI

What implications has your theory on menstrual bleeding for the treatment of reproductive tract diseases?

Profet

Physicians have always thought it's the bleeding that's bad. The emphasis in so much of the IUD and infection literature is on suppressing this bleeding because it's causing the infection. According to my view, an abnormally heavy period could indicate possible infection. If your period suddenly doubles, and it's more frequent and you haven't been pregnant, then go see a physician.

OMNI

You challenge the view in many cultures that menstruating women are "unclean." Your theory says women cleanse themselves of pathogens introduced by dirty sperm.

Profet

It's not like it's anyone's fault. The sperm may be vectors, but most of the pathogens they're carrying are from the vagina and cervix. The transfer of pathogens to the uterus and oviducts is an unavoidable concomitant of internal fertilization. I'm not sure anyone likes menstruation. Why would they? But one way my theory may help is that many men hold a disdainful attitude toward menstruation and of women as having to go through this bizarre, wasteful, girly thing. Maybe now they'll have a little more respect for it, though I personally anticipate getting every menstruation joke in the book. My grandpa made the first one, and he's 84 years old.

You know, I never set out to prove menstruation is there for a purpose. Menstruation has always been one of the little annoying things, but it's not a major thing in my life. Undergoing something often enhances your insights about it. But that's not a feminist perspective. Allergy is a male-female phenomenon. I'm interested in these anomalies, these things that on the surface don't seem to make sense whether they occur in males or females.

OMNI

You've come up with these new interpretations of processes affecting women. Have people called you a radical feminist?

Profet

If someone doesn't bother reading my papers, sure, they might assume this is some radical feminist proposal. It has nothing to do with feminism. I do not warp my science for the sake of any particular ideology. I don't do feminist biology. I do biological science. Saying that sperm are vectors for pathogens is a scientific statement, not a feminist statement. There's a huge literature to support this. Sperm are vectors in all mammals. This isn't something tailored for Ms. magazine. My hypothesis about menstruation has three complementary lines of evidence: adaptive design, comparative mammalian and clinical data.

OMNI

But science isn't as objective as one might like to think. We may all agree about method, but we may see things or be affected by our individual eyes and backgrounds?

Profet

Your initial insights might be, but you do what's humanly possible to be objective, given the data. I never set out to prove menstruation is there for a purpose. Menstruation has always been one of the little annoying things, but it's not a major thing in my life. Undergoing something often enhances your insights about it. But that's not a feminist perspective. It's not as if I was out to justify these things. Allergy is a male-female phenomenon. I'm interested in these anomalies, these things that on the surface just don't seem to make sense whether they occur in males or females. I certainly have more experience with menstruation than a male's going to have; I do have allergies, so I get interested and involved for various reasons.

OMNI

How did your undergraduate work in physics and political philosophy lead you to research in evolutionary biology?

Profet

As an undergraduate, I wanted a classical philosophy training. I wanted to read, think, write a few papers. Philosophy was great training for thinking, but I didn't feel I had the knowledge or power to get answers. To understand any question about nature, even human nature, you really have to know science, because any question about nature is a scientific question. Physics is extremely elegant, a beautiful thing to understand. But I was so turned off by the regimentation of the classroom that by my last year of physics, I felt I was sleepwalking most of the time. I liked "why" questions, but figured the kinds of questions I liked in physics--like why is the speed of light what it is--I wouldn't have the foggiest idea how to solve. So I decided to just read whatever I felt like in the universe and gravitated toward evolutionary biology.

OMNI

What do you hope to achieve with your work?

Profet

I hope it will have major clinical implications but in a broader sense will start to change the approach to medicine. If there's a physiological phenomenon, the first question should be, Does it have a function? Look for the evidence of adaptation and then figure out what the function is. Only then can you understand whether you should treat the symptoms, what the costs of treating or not treating are, and what it means to have this mechanism in a modern society versus the Pleistocene environment in which it evolved.

Today, medicine tends to have a condensceding attitude towards these questions. When William Harvey in the seventeenth century figured out the function of the heart is to pump blood, he was ridiculed mercilessly. He'd done beautiful experiments, and said, look at the design of the heart, it's like a pump. Treatises were written about how preposterous was the notion that blood circulates. Ha, ha, ha. Some people still feel that way: "The function of allergies or pregnancy sickness--these are mere intellectual gymnastics, just side interest stories, nothing to do with medicine." No, they are essential to medicine. Instead, some doctors go messing up people's systems, interfering without understanding what the mechanism is there for.

OMNI

Can lay people benefit from evolutionary knowledge?

Profet

Very much. The pregnancy work struck a chord in many women. It made sense. They were visibly happier about their pregnancies One women was miserable in the first trimester, but then she found out why and her attitude completely changed. She felt she was doing something for the baby. I hope my book will give them sufficient information about what they should eat and avoid.

OMNI

Medicine tries to intervene to ensure we function properly. Your work suggests many thing we have construed as maladaptive actually serve evolutionary functions. Does the medical world misunderstand "function" and "dysfunction?"

Profet

They really suffer from it. In my menstruation paper I quoted someone who was trying to define what a normal degree of menstruation was and asked, but what is normal value for a process that is not needed? You can't define normal when you don't understand what it's there for. Physicians pretty much look at anything not understood and assume it's a mistake. Pregnancy sickness is dysfunctional; allergy is a mistake. Menstruation is a fluke. If it's a mistake they think they should intervene whenever they can. But there are some terrible consequences of that. Thalidomide was possibly the worst. Many women were given thalidomide, a terrible teratogen, for their pregnancy sickness.

What's really bad, is when physicians who don't really understand evolutionary theory, but want to come up with an evolutionary theory of their own, even a one-sentence, half-baked speculation. People not well-versed in evolutionary theory usually don't understand there are standards for adaptationist analysis. Theory means you have rigorous work behind it. One woman thought the function of morning sickness is to give a woman a heightened sense of smell so you can waddle away faster from predators or fire, because you have increased bulk during pregnancy and need advanced warning. But you have a heightened sense of smeel in the first trimester when you don't have a lot of bulk, and a subnormal sense of smell in the third trimester when you have a lot of bulk.

OMNI

Have you considered medical training?

Profet

It is completely nontheoretical. I don't want to be a doctor.

OMNI

When did you become an adaptationist?

Profet

I was doing it long before I realized there was that word. I don't think I heard the term adaptationist program until I came up with my three main ideas.

OMNI

Does your perspective stem from the fact you're out of academe?

Profet

It's because I'm not locked into it and refuse to allow myself to be. Many people think what's important is to get the credentials. No, what's important is the science. The way you judge your own life and the way you will be judged is by the work. When you die, who's going to care what credentials you accumulate? If you spend your youth getting credentials and you're not excited about what you're doing, you're missing the great time for science. I defied all the supposed rules; I have zero credentials in my field. I have no Ph.D. in anything. I don't dress or look like a professor. I don't give talks; I'm hermitlike. I don't do those normal things, but my stuff gets published.

OMNI

Yet you spent six, as you said, hideous months in graduate school.

Profet

I went out of financial desperation. I was living in a converted dining room of an apartment. I didn't even have a door to separate me from noisy undergraduate roommates. Somebody convinced me I could go to Harvard and they'd basically let me do my own work and get paid for it. It wasn't like that. I would have quit immediately in the first week if I'd had the money. But I was getting funded; it was mind control. It's just horrible when somebody tries to control your mind and you have no way out because you're impoverished.

When you have such low official status, people who'd normally be nice become unbearably condescending and patronizing. They'd ask: "What do you do?" You can't say, Oh, I'm thinking, so you say, Oh, I'm being a bum, because even if you don't say it, they treat you like a bum who's wasted a life. So I came back, got my old job back. And now that I've won the MacArthur, people have ask, strangely, if I'm doing to get a Ph.D. Why on earth? I won. I don't ever have to put up with that garbage again. Never again.

OMNI

What are you going to do when the MacArthur runs out?

Profet

I'm going to keep doing this, and hope someone starts the Institute for Darwinian Medicine, a think tank for scientists who don't fit into the pattern and regimentation of a university. On the West Coast, somewhere with a nice view.