Some evolutionary theorists see evolution as improvisational, proceeding almost haphazardly. Others, like Profet, see it as more disciplined, as a careful weighing of costs and benefits. If some significant feature of life evolves in a certain way, there must be a reason for it. [bngenoh: DUH]
THERE IS IN ANY POPULATION variation among its members. With human beings, for example, some are tall, some short, some of medium height. A statistician wanting to describe how tall a person was relative to other people might plot the distribution of heights on a graph. When plotted, heights describe a bell-shaped curve. A very few, very tall people are at one edge of the bell; a very few, very short people are at the other. Most people fall somewhere in between, bulging along the middle of the graph, the so-called norm. One common measure of distance from this norm is called a sigma after the Greek letter that is used to represent its formula.
So if the average height of American women was 5 feet 4 inches, someone who was 5 feet 7 might be one sigma away from the norm. A 6-foot woman might be three sigmas, a 7-footer five sigmas.
I remember when I was learning about evolution, and it was emphatically stated that evolution only occurs in populations, it doesn't occur in individuals, I thought huh, why the hell not, does it just spring up from nowhere? The basis of evolution is variation, individuals are the units of variation in a given population, but let's continue:
"I'm allergic to a lot of things, mostly detergents and things like that," she says. "One night, when I didn't know exactly what I was allergic to yet, I'm in bed scratching and I just remember thinking: `What is this for?'
"I knew because I had studied some immunology that there was this whole class of antibodies that does nothing but cause allergies. And I thought, `What on earth could it be there for?' I thought, `What are the symptoms of allergy?'
"It's immediate. It's unlike a viral illness or a bacteria, which are delayed, and might be days before you get any noticeable reaction. With allergies, it's immediate, within minutes. You're scratching it off, you're tearing, you're sneezing, you have diarrhea, or you vomit and you drop your blood pressure. All of these are ways to immediately expel something.
"I thought, `What could cause this? What could kill you within minutes? Viruses don't work that fast. Bacteria don't. Toxins do.' "
Profet had no idea at the time what the conventional analyses of allergy were. When she found out that most scientists believed it was either, one, a mistake, or two, a reaction to the potential presence of parasitic helminth worms in the digestive track, she was appalled.
"When I came across the helminth worm theory, I thought, `NO, they couldn't be taking this seriously. Maybe one or two immunologists think this is the reason, but this is beyond silliness.' [ blunt and to the point, my kind of gal]
"It doesn't make sense from an adaptationist viewpoint because there's not a fit between the mechanisms of allergy and the problem of worm expulsion," she says. "Worms are a chronic problem, and allergies were designed for something acute."
For reasons neither Williams nor Profet can fathom, physicians and biologists, who, after all, share the human body as a subject, seldom were aware of one another's work.
Profet says, "Physicians don't look at function. Physicians seem to think if you ask what's the function of something, it's teleological. It's an intellectual theory, and there's no practical utility.
"It's not important? It's the basis, it's the foundation for understanding physiology. And physiology is the basis for understanding medicine. Imagine if we didn't understand the function of the heart. How could you recognize heart disease? How could you define heart health? How could you do anything? How could you perform heart surgery? How would you know when to do it? What to do?"
"Science isn't a democracy," Profet says. "Voting is not the basis for truth. You don't go to some allergist and say, can I have a show of hands? That's not how you demonstrate science. I find things like that mind-boggling. [bngenoh:TRUTH]
"You know, you tell any lay person, `Guess what the immunologists think that allergy is designed for.'
"They say, `What?'
"And you say, `Little worms.'
"And they go, `Huh?' "
It is this intuitive grasp of the apparent failure of existing theory that is the basis for all of Profet's work. Her three major ideas - on pregnancy sickness, allergy and menstruation - all subject anomalous human behavior to an adaptationist critique. Why does this happen? What does it cost? What is the resulting benefit? The fundamental supposition of evolution, that all organisms are engaged in an evolutionary race for survival, is the main motivation of all of her explorations.
Most modern scientists are grown in much the same way as today's crops. They are lined up all in a row, standardized, carefully fertilized and watered, grown to uniform size. They have been domesticated. Profet is a throwback to the days before domestication. She is a precursor, foraging through the fields of human knowledge, searching for some things, happening upon others.
In her own evolutionary race, she seems to have outlasted her natural enemies. The hunter-gatherer has come back.
Got the allergy paper abstract:
This paper proposes that the mammalian immune response known as "allergy" evolved as a last line of defense against the extensive array of toxic substances that exist in the environment in the form of secondary plant compounds and venoms. Whereas nonimmunological defenses typically can target only classes of toxins, the immune system is uniquely capable of the fine-tuning required to target selectively the specific molecular configurations of individual toxins. Toxic substances are commonly allergenic. The pharmacological chemicals released by the body's mast cells during an IgE antibody-mediated allergic response typically cause vomiting, diarrhea, coughing, tearing, sneezing, or scratching, which help to expel from the body the toxic substance that triggered the response; individuals frequently develop aversions to substances that have triggered such responses. A strong allergic response often includes a decrease in blood pressure, which slows the rate at which toxins circulate to target organs. The immune system identifies as toxic the following kinds of substances: (1) those low-molecular-weight substances that bind covalently to serum proteins (e.g., many plant toxins); (2) nontoxic proteins that act as carriers of toxins with low molecular weights (e.g., plant proteins associated with plant toxins); (3) specific substances of high molecular weight that harmed individuals in ancestral mammalian populations for a span of time that was significant from the standpoint of natural selection (e.g., the toxic proteins of bee venom). Substances that bind covalently to serum proteins generally are acutely toxic, and because many of these substances also bind covalently to the DNA of target cells, they are potentially mutagenic and carcinogenic as well. Thus, by protecting against acute toxicity, allergy may also defend against mutagens and carcinogens.The toxin hypothesis explains the main phenomena of allergy: why IgE-mediated allergies usually occur within minutes of exposure to an allergen and why they are often so severe; why the manifestations of allergy include vomiting, diarrhea, coughing, sneezing, scratching, tearing, and a drop in blood pressure; why covalent binding of low-molecular-weights substances to serum proteins frequently causes allergy; why allergies occur to many foods, pollens, venoms, metals, and drugs; why allergic cross-reactivity occurs to foods and pollen from unrelated botanical families; why allergy appears to be so capricious and variable; and why allergy is more prevalent in industrial societies than it is in foraging societies. This hypothesis also has implications for the diagnosis, prevention, and treatment of allergy.
More of her papers: _http://www.jstor.org/action/doBasicSearch?filter=jid%3A10.2307%2Fj100336&Query=Margie+Profet&Search.x=0&Search.y=0&wc=on
Needless to say, this merits a trip to the college for full access and a lot of printing.