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Mar

2012

The Meming of Life » Unnatural Parenting Beyond Belief on secular parenting and other natural wonders

You’ve got to be taught to be afraid / Of people whose eyes are oddly made,
And people whose skin is a diff’rent shade / You’ve got to be carefully taught.

You’ve got to be taught before it’s too late / Before you are six or seven or eight,
To hate all the people your relatives hate / You’ve got to be carefully taught!

–from the Rodgers and Hammerstein musical South Pacific (1949)

parentingbeyondbelief.com/blog

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Nature Nurture

Feb

2012

Nature, nurture and liberal values | Prospect Magazine

culture is an adaptation, which exists because it conferred a reproductive advantage on our hunter-gatherer ancestors. According to this view many of the diverse customs that the standard social science model attributes to nurture are local variations of attributes acquired 70 or more millennia ago, during the Pleistocene age, and now (like other evolutionary adaptations) “hard-wired in the brain.” But if this is so, cultural characteristics may not be as plastic as the social scientists suggest. There are features of the human condition, such as gender roles, that people have believed to be cultural and therefore changeable. But if culture is an aspect of nature, “cultural” does not mean “changeable.” Maybe these controversial features of human culture are part of the genetic endowment of human kind.

www.prospectmagazine.co.uk/...nz-david-eagleman-neuroscience

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Culture Nature Nurture Gender Stereotype

If we follow the evolutionary biologists, therefore, we may find ourselves pushed towards accepting that traits often attributed to culture may be part of our genetic inheritance, and therefore not as changeable as many might have hoped: gender differences, intelligence, belligerence, and so on through all the characteristics that people have wished, for whatever reason, to rescue from destiny and refashion as choice.

Jan

2012

Socialists and conservatives may be born not made | Carole Jahme | Science | guardian.co.uk

The research published online last week by the Royal Society indicates that where you put your cross on the ballot paper on polling day is, at least in part, instinctive. In other words, socialists and conservatives may be born not made.

www.guardian.co.uk/...ts-conservatives-born-not-made

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Nature Nurture Politics Liberal Conservative

This research builds on earlier evidence of correlations between empathetic traits/moral values and political affiliation, and correlations between threat/disgust reflexes and political affiliation. Those scoring higher on disgust/threat indexes are more likely to score lower on empathy and vote conservative, whereas those scoring higher on maximising equality and minimising harm are more likely to score higher in empathy and be left wing.
Sex differences are also highlighted by these measures, with females (or males with higher than average levels of empathy) more likely than average males to overcome their feelings of disgust or threat and vote left wing.

Jan

2012

Cynthia Nixon’s Life After ‘Sex’ - NYTimes.com

“I gave a speech recently, an empowerment speech to a gay audience, and it included the line ‘I’ve been straight and I’ve been gay, and gay is better.’ And they tried to get me to change it, because they said it implies that homosexuality can be a choice. And for me, it is a choice. I understand that for many people it’s not, but for me it’s a choice, and you don’t get to define my gayness for me. A certain section of our community is very concerned that it not be seen as a choice, because if it’s a choice, then we could opt out. I say it doesn’t matter if we flew here or we swam here, it matters that we are here and we are one group and let us stop trying to make a litmus test for who is considered gay and who is not.” Her face was red and her arms were waving. “As you can tell,” she said, “I am very annoyed about this issue. Why can’t it be a choice? Why is that any less legitimate? It seems we’re just ceding this point to bigots who are demanding it, and I don’t think that they should define the terms of the debate. I also feel like people think I was walking around in a cloud and didn’t realize I was gay, which I find really offensive. I find it offensive to me, but I also find it offensive to all the men I’ve been out with.”

www.nytimes.com/...cynthia-nixon-wit.html

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Sexuality Nature Nurture

Sep

2011

The Pink Menace « Quiet Riot Girl

An article in today’s (UK) Telegraph, tells us of some new research. The findings of the study show:

‘that young girls do indeed have a special affinity for the colour pink that appears sometime in the second half of the second year’ and that ‘while girls are developing a preference for pink with age, boys are developing an avoidance of pink at the same time’.

quietgirlriot.wordpress.com/...the-pink-menace

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Gender Stereotype Gender Equality Nurture

for those of us who have been arguing that gender difference, on the whole, between ‘boys’ and ‘girls’ is not innate but learned. I was born into a militant feminist household in the early 1970s, and I never became attached to the colour pink. I have not even seen a photo of me as a young baby or toddler in any pink garment.

But the article is interesting for another reason. It very much focuses on the colour pink as a signifier of gender difference. Apart from the quoted mention of boys having blue lunchboxes above, there is no discussion of boys becoming ‘attached’ to the colour blue in the article.
The Telegraph states:

‘The academics say that previous studies have shown that between the ages of two and three, children begin to talk about gender and “seek out” information about it.

“Thus, if the colour pink is part of what identifies ‘girliness’, then it is not surprising that girls at this age are attracted to it,” they write.

At the same time, “as boys learn what it means to be a girl, they being to avoid anything that can possibly define ‘girliness’”.’
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- So for boys, pink is something to avoid because it signifies ‘girliness’. But blue does not really signify ‘boyness’ does it? This is an example of how, in our culture, being a boy or a man is often defined as being ‘not a girl’ or ‘not a woman’. And boys and men spend a lot of their time avoiding that which might identify them as ‘girly’ or ‘feminine’. Or denying the ‘girliness’ that they themselves display.
- As boys grow up, the colour pink also becomes associated with being ‘gay’ but The Telegraph avoids this issue as if it were a boy, shunning all things pink. Gay rights groups though, have ‘reclaimed’ the colour Pink, and turned it into a sign of their ‘gay pride’. So now we have the ‘pink pound’ and publications such as Pink News, which use the colour to signify gay masculinities. Personally, I am not enamoured of ‘pink for a gay’. It is too similar to the gender essentialism of ‘pink for a girl’. And I do not know of a ‘macho’ or ‘anti-gay’ paper called ‘Blue News’. It is the colour pink that is dangerous and powerful, that men avoid, but also are preoccupied with, like the great big pink throbbing elephant of homo-anxiety in the corner of the room.
- This is illustrated quite beautifully and at times poignantly by Sarah Hoffman, on her blog about her son, Pink Boy – a boy who is different. The difference between Sarah’s son and other boys, like the difference between me and other girls when I was growing up, is that he has not chosen to attach himself to the ‘appropriate’ colour for his gender identity, and he has not been ‘coerced’ to do so by his parent(s) either. He loves pink. And sometimes he wears pink skirts or dresses, and plays with pink toys. But the difference between me and Sarah’s boy, is that even back in the 1970s it wasn’t a big deal for girls to ‘go against’ their allotted gendered behaviours. For boys, even now in 2011, it is seen as weird, as ‘girly’, as perverse, and as potentially ‘gay’ for boys to like the colour pink. So weird that Sarah now spends some of her time writing about her son, in the hope that one day, people won’t be quite so weird in their obsession with the old adage of ‘pink for a girl, blue for a boy’.

Aug

2011

What Makes People Gay? - The Boston Globe

www.boston.com/...what_makes_people_gay

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Sexuality Homosexuality Nature Nurture Conceptualization Paradigm Genetic

What makes the case of Patrick and Thomas so fascinating is that it calls into question both of the dominant theories in the long-running debate over what makes people gay: nature or nurture, genes or learned behavior. As identical twins, Patrick and Thomas began as genetic clones. From the moment they came out of their mother's womb, their environment was about as close to identical as possible - being fed, changed, and plopped into their car seats the same way, having similar relationships with the same nurturing father and mother. Yet before either boy could talk, one showed highly feminine traits while the other appeared to be "all boy," as the moms at the playgrounds say with apologetic shrugs.
in 1991, a neuroscientist in San Diego named Simon LeVay told the world he had found a key difference between the brains of homosexual and heterosexual men he studied. LeVay showed that a tiny clump of neurons of the anterior hypothalamus - which is believed to control sexual behavior - was, on average, more than twice the size in heterosexual men as in homosexual men. LeVay's findings did not speak directly to the nature-vs.-nurture debate - the clumps could, theoretically, have changed size because of homosexual behavior. But that seemed unlikely, and the study ended up jump-starting the effort to prove a biological basis for homosexuality.
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- Boston University psychiatrist Richard Pillard and Northwestern University psychologist J. Michael Bailey announced the results of their study of male twins. They found that, in identical twins, if one twin was gay, the other had about a 50 percent chance of also being gay. For fraternal twins, the rate was about 20 percent. Because identical twins share their entire genetic makeup while fraternal twins share about half, genes were believed to explain the difference. Most reputable studies find the rate of homosexuality in the general population to be 2 to 4 percent, rather than the popular "1 in 10" estimate.
- In 1993 came the biggest news: Dean Hamer's discovery of the "gay gene." In fact, Hamer, a Harvard-trained researcher at the National Cancer Institute, hadn't quite put it that boldly or imprecisely. He found that gay brothers shared a specific region of the X chromosome, called Xq28, at a higher rate than gay men shared with their straight brothers. Hamer and others suggested this finding would eventually transform our understanding of sexual orientation.
- Researchers at Northwestern University, outside Chicago, are doing this work as a follow-up to their studies of arousal using genital measurement tools. They found that while straight men were aroused by film clips of two women having sex, and gay men were aroused by clips of two men having sex, most of the men who identified themselves as bisexual showed gay arousal patterns. More surprising was just how different the story with women turned out to be. Most women, whether they identified as straight, lesbian, or bisexual, were significantly aroused by straight, gay, and lesbian sex. "I'm not suggesting that most women are bisexual," says Michael Bailey, the psychology professor whose lab conducted the studies. "I'm suggesting that whatever a woman's sexual arousal pattern is, it has little to do with her sexual orientation." That's fundamentally different from men. "In men, arousal is orientation. It's as simple as that. That's how gay men learn they are gay."
- researchers need a far deeper understanding of what sexual orientation is before they can determine where it comes from.
- Female sexual orientation is particularly foggy, he says, because there's been so little research done. As for male sexual orientation, he argues that there's now enough evidence to suggest it is "entirely in-born," though not nearly enough to establish how that happens.
- Bailey's 1991 twin study is still cited by other researchers as one of the pillars in the genetic argument for homosexuality. But his follow-up study using a comprehensive registry of twins in Australia found a much lower rate of similarity in sexual orientation between identical twins, about 20 percent, down from 50 percent.
- Cornell psychologist Daryl Bem has proposed an intriguing theory for how CGN might lead to homosexuality. According to this pathway, which he calls "the exotic becomes erotic," children are born with traits for temperament, such as aggression and activity level, that predispose them to male-typical or female-typical activities. They seek out playmates with the same interests. So a boy whose traits lead him to hopscotch and away from rough play will feel different from, and ostracized by, other boys. This leads to physiological arousal of fear and anger in their presence, arousal that eventually is transformed from exotic to erotic.
  
  Critics of homosexuality have used Bem's theory, which stresses environment over biology, to argue that sexual orientation is not inborn and not fixed. But Bem says this pathway is triggered by biological traits, and he doesn't really see how the outcome of homosexuality can be changed.
- Males and females have a fundamental genetic difference - females have two X chromosomes, and males have an X and a Y. Still, right after conception, it's hard to tell male and female zygotes apart, except for that tucked-away chromosomal difference. Normally, the changes take shape at a key point of fetal development, when the male brain is masculinized by sex hormones. The female brain is the default. The brain will stay on the female path as long as it is protected from exposure to hormones. The hormonal theory of homosexuality holds that, just as exposure to circulating sex hormones determines whether a fetus will be male or female, such exposure must also influence sexual orientation.
- The cases of children born with disorders of "sexual differentiation" offer insight. William Reiner, a psychiatrist and urologist with the University of Oklahoma, has evaluated more than a hundred of these cases. For decades, the standard medical response to boys born with severely inadequate penises (or none at all) was to castrate the boy and have his parents raise him as a girl. But Reiner has found that nurture - even when it involves surgery soon after birth - cannot trump nature. Of the boys with inadequate penises who were raised as girls, he says, "I haven't found one who is sexually attracted to males." The majority of them have transitioned back to being males and report being attracted to females.
- During fetal development, sexual identity is set before the sexual organs are formed, Reiner says. Perhaps it's the same for sexual orientation. In his research, of all the babies with X and Y chromosomes who were raised as girls, the only ones he has found who report having female identities and being attracted to males are those who did not have "receptors" to let the male sex hormones do their masculinizing in the womb.
- "Exposure to male hormones in utero dramatically raises the chances of being sexually attracted to females," Reiner says. "We can infer that the absence of male hormone exposure may have something to do with attraction to males."
- New York University researcher Lynn S. Hall, who has studied traits determined in the womb, speculates that Patrick was somehow prenatally stressed, probably during the first trimester, when the brain is really developing, particularly the structures like the hypothalamus that influence sexual behavior. This stress might have been based on his position in the womb or the blood flow to him or any of a number of other factors not in his mother's control. Yet more evidence that identical twins have womb experiences far from identical can be found in their often differing birth weights. Patrick was born a pound lighter than Thomas.
- the research suggests that early on in the womb, as the fetus's brain develops in either the male or female direction, something fundamental to sexual orientation is happening. Nobody's sure what's causing it. But here's where genes may be involved, perhaps by regulating hormone exposure or by dictating the size of that key clump of neurons in the hypothalamus. Before researchers can sort that out, they'll need to return to the question of whether, in fact, there is a "gay gene."
- There is, however, a towering question that Sanders's study will probably not be able to answer. That has to do with evolution. If a prime motivation of all species is to pass genes on to future generations, and gay men are estimated to produce 80 percent fewer offspring than straight men, why would a gay gene not have been wiped out by the forces of natural selection? This evolutionary disadvantage is what led former Amherst College biologist Paul Ewald to argue that homosexuality might be caused by a virus - a pathogen most likely working in utero. That argument caused a stir when he and a colleague proposed it six years ago, but with no research done to test it, it remains just another theory. Other scientists have offered fascinating but unpersuasive explanations, most of them focusing on some kind of compensatory benefit, in the same way that the gene responsible for sickle cell anemia also protects against malaria. A study last year by researchers in Italy showed that female relatives of gay men tended to be more fertile, though, as critics point out, not nearly fertile enough to make up for the gay man's lack of offspring.
- Those same genes would work one way in heterosexual women and another way in homosexual men. The UCLA lab is examining how these genes might be turned "up" or "down." It's not a question of what genes you have, but rather which ones you use, says Bocklandt. "I have the genes in my body to make a vagina and carry a baby, but I don't use them, because I am a man." In studying the genes of gay sheep, for example, he's found some that are turned "way up" compared with the straight rams.

Jun

2011

Genetic Sequencing Will Have to Wait: Links Between Genes and Behavior Still Largely Unknown | The Utopianist - Think Bigger

All of these genetic links to common issues are fundamentally the same in how they work — they involve many genes that don’t determine our fate but rather impact how we react to our environment. The potential benefits to understanding this relationship are immense, and much progress is being made. As scientists learn more about how these intricate relationships work, they will hopefully be able to develop personalized treatments for people struggling from a variety of ailments. Until then, genetic sequencing for the public will have to wait — the relatively little information we have so far would likely only lead to faulty conclusions, made in an attempt to form that simple, big picture we always expect from science.

utopianist.com/...behavior-still-largely-unknown

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Genetic Crime Sociology Nature Nurture Bioethics Depression Neuropsychology

A recent article in The New York Times reported that over 100 studies show a relationship between genes and criminality but that the environment plays a key role in the effects of this relationship:

“Kevin Beaver, an associate professor at Florida State University’s College of Criminology and Criminal Justice, said genetics may account for, say, half of a person’s aggressive behavior, but that 50 percent comprises hundreds or thousands of genes that express themselves differently depending on the environment.

He has tried to measure which circumstances — having delinquent friends, living in a disadvantaged neighborhood — influence whether a predisposition to violence surfaces. After studying twins and siblings, he came up with an astonishing result: In boys not exposed to the risk factors, genetics played no role in any of their violent behavior. The positive environment had prevented the genetic switches — to use Mr. Pinker’s word — that affect aggression from being turned on. In boys with eight or more risk factors, however, genes explained 80 percent of their violence. Their switches had been flipped.”
In fact, environment plays the same crucial role for criminality as it does for obesity and depression.

In an interview I did for a story in The Michigan Daily on depression research, Dr. Margit Burmeister, a professor of human genetics and a researcher in the Molecular and Biological Neuroscience Institute at the University of Michigan, explained the dangers the public oversimplifying the link between genetics and depression:
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- “This idea that if something is genetic it’s deterministic is a misconception that we have to get over because saying that genes are involved in depression does not necessarily mean that someone who has certain genetic variants is doomed to become depressed, it just means that under certain circumstances, he or she may have to do certain things to help alleviate it, but it’s not unchangeable. You can change your brain, you can change your brain in many different ways and genetics is just one of many of these ways.”

May

2011

It’s Even Less in Your Genes by Richard C. Lewontin | The New York Review of Books

In trying to analyze the natural world, scientists are seldom aware of the degree to which their ideas are influenced both by their way of perceiving the everyday world and by the constraints that our cognitive development puts on our formulations. At every moment of perception of the world around us, we isolate objects as discrete entities with clear boundaries while we relegate the rest to a background in which the objects exist.

That tendency, as Evelyn Fox Keller’s new book suggests, is one of the most powerful influences on our scientific understanding. As we change our intent, also we identify anew what is object and what is background.

www.nybooks.com/...its-even-less-your-genes

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Genetic Nature Nurture Causation Heritable Heritability

Although classic Darwinism is framed by referring to organisms adapting to environments, the actual process of evolution involves the creation of new “ecological niches” as new life forms come into existence. Part of the ecological niche of an earthworm is the tunnel excavated by the worm and part of the ecological niche of a tree is the assemblage of fungi associated with the tree’s root system that provide it with nutrients.
The vulgarization of Darwinism that sees the “struggle for existence” as nothing but the competition for some environmental resource in short supply ignores the large body of evidence about the actual complexity of the relationship between organisms and their resources. First, despite the standard models created by ecologists in which survivorship decreases with increasing population density, the survival of individuals in a population is often greatest not when their “competitors” are at their lowest density but at an intermediate one. That is because organisms are involved not only in the consumption of resources, but in their creation as well. For example, in fruit flies, which live on yeast, the worm-like immature stages of the fly tunnel into rotting fruit, creating more surface on which the yeast can grow, so that, up to a point, the more larvae, the greater the amount of food available. Fruit flies are not only consumers but also farmers.
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- Second, the presence in close proximity of individual organisms that are genetically different can increase the growth rate of a given type, presumably since they exude growth-promoting substances into the soil. If a rice plant of a particular type is planted so that it is surrounded by rice plants of a different type, it will give a higher yield than if surrounded by its own type. This phenomenon, known for more than a half-century, is the basis of a common practice of mixed-variety rice cultivation in China, and mixed-crop planting has become a method used by practitioners of organic agriculture.
- Despite the evidence that organisms do not simply use resources present in the environment but, through their life activities, produce such resources and manufacture their environments, the distinction between organisms and their environments remains deeply embedded in our consciousness
- the problem is deeper than simply intellectual inertia. It goes back, ultimately, to the unconsidered differentiations we make—at every moment when we distinguish among objects—between those in the foreground of our consciousness and the background places in which the objects happen to be situated. Moreover, this distinction creates a hierarchy of objects. We are conscious not only of the skin that encloses and defines the object, but of bits and pieces of that object, each of which must have its own “skin.” That is the problem of anatomization. A car has a motor and brakes and a transmission and an outer body that, at appropriate moments, become separate objects of our consciousness, objects that at least some knowledgeable person recognizes as coherent entities.
- Evelyn Fox Keller sees “The Mirage of a Space Between Nature and Nurture” as a consequence of our false division of the world into living objects without sufficient consideration of the external milieu in which they are embedded, since organisms help create effective environments through their own life activities. Fox Keller is one of the most sophisticated and intelligent analysts of the social and psychological forces that operate in intellectual life and, in particular, of the relation of gender in our society both to the creation and acceptance of scientific ideas. The central point of her analysis has been that gender itself (as opposed to sex) is socially constructed, and that construction has influenced the development of science:
  If there is a single point on which all feminist scholarship…has converged, it is the importance of recognizing the social construction of gender…. All of my work on gender and science proceeds from this basic recognition. My endeavor has been to call attention to the ways in which the social construction of a binary opposition between “masculine” and “feminine” has influenced the social construction of science.
- It is, for example, all very well to say that genetic variation is responsible for 76 percent of the observed variation in adult height among American women while the remaining 24 percent is a consequence of differences in nutrition. The implication is that if all variation in nutrition were abolished then 24 percent of the observed height variation among individuals in the population in the next generation would disappear. To say, however, that 76 percent of Evelyn Fox Keller’s height was caused by her genes and 24 percent by her nutrition does not make sense. The nonsensical implication of trying to partition the causes of her individual height would be that if she never ate anything she would still be three quarters as tall as she is.
- Keller is too optimistic about the assignment of causes of variation even when considering variation in a population. As she herself notes parenthetically, the assignment of relative proportions of population variation to different causes in a population depends on there being no specific interaction between the causes. She gives as a simple example the sound of two different drummers playing at a distance from us. If each drummer plays each drum for us, we should be able to tell the effect of different drummers as opposed to differences between drums. But she admits that is only true if the drummers themselves do not change their ways of playing when they change drums.
- If there are several variable factors influencing some phenomenon, how are we to assign the relative importance to each in determining total variation?
- Suppose that we plant seeds of each of two different varieties of corn in two different locations with the following results measured in bushels of corn produced (see Table 1).
  
  There are differences between the varieties in their yield from location to location and there are differences between locations from variety to variety. So, both variety and location matter. But there is no average variation between locations when averaged over varieties or between varieties when averaged over locations. Just by knowing the variation in yield associated with location and variety separately does not tell us which factor is the more important source of variation; nor do the facts of location and variety exhaust the description of that variation.
- There is a third source of variation called the “interaction,” the variation that cannot be accounted for simply by the separate average effects of location and variety. There is no difference that appears between the average of different varieties or average of different locations, suggesting that neither location or variety matters to yield. Yet the yields of corn were different when different particular combinations of variety and location are observed. These effects of particular combinations of factors, not accounted for by the average effects of each factor separately, are thrown into an unanalyzed category called “interaction” with no concrete physical model made explicit.
- The Mirage of a Space Between Nature and Nurture appears in an era when biological—and specifically, genetic—causation is taken as the preferred explanation for all human physical differences. Although the early and mid-twentieth century was a period of immense popularity of genetic explanations for class and race differences in mental ability and temperament, especially among social scientists, such theories have now virtually disappeared from public view
- Ironically, at the same time that genetics has ceased to be a popular explanation for human intellectual and temperamental differences, genetic theories for the causation of virtually every physical disorder have become the mode.
- DNA studies of disease causation had a “relatively low impact.” Both of these articles were instigated by several articles in The New England Journal of Medicine, which had come to the conclusion that the search for genes underlying common causes of mortality had so far yielded virtually nothing useful. The failure to find such genes continues and it seems likely that the search for the genes causing most common diseases will go the way of the search for the genes for IQ.
- A major problem in understanding what geneticists have found out about the relation between genes and manifest characteristics of organisms is an overly flexible use of language that creates ambiguities of meaning. In particular, their use of the terms “heritable” and “heritability” is so confusing
- When a biological characteristic is said to be “heritable,” it means that it is capable of being transmitted from parents to offspring, just as money may be inherited, although neither is inevitable. In contrast, “heritability” is a statistical concept, the proportion of variation of a characteristic in a population that is attributable to genetic variation among individuals. The implication of “heritability” is that some proportion of the next generation will possess it.
- The move from “heritable” to “heritability” is a switch from a qualitative property at the level of an individual to a statistical characterization of a population. Of course, to have a nonzero heritability in a population, a trait must be heritable at the individual level. But it is important to note that even a trait that is perfectly heritable at the individual level might have essentially zero heritability at the population level. If I possess a unique genetic variant that enables me with no effort at all to perform a task that many other people have learned to do only after great effort, then that ability is heritable in me and may possibly be passed on to my children, but it may also be of zero heritability in the population.
- One of the problems of exploring an intellectual discipline from the outside is that the importance of certain basic methodological considerations is not always apparent to the observer, considerations that mold the entire intellectual structure that characterizes the field. So, in her first chapter, “Nature and Nurture as Alternatives,” Fox Keller writes that “my concern is with the tendency to think of nature and nurture as separable and hence as comparable, as forces to which relative strength can be assigned.” That concern is entirely appropriate for an external critic, and especially one who, like Fox Keller, comes from theoretical physics rather than experimental biology. Experimental geneticists, however, find environmental effects a serious distraction from the study of genetic and molecular mechanisms that are at the center of their interest, so they do their best to work with cases in which environmental effects are at a minimum or in which those effects can be manipulated at will. If the machine model of organisms that underlies our entire approach to the study of biology is to work for us, we must restrict our objects of study to those in which we can observe and manipulate all the gears and levers
- Genetics, from its very beginning, has been a “subtractive” science. That is, it is based on the analysis of the difference between natural or “wild-type” organisms and those with some genetic defect that may interfere in some observable way with regular function. But to carry out such comparison it is necessary that the organisms being studied are, to the extent possible, identical in all other respects, and that the comparison is carried out in an environment that does not, itself, generate atypical responses yet allows the possible effect of the genetic perturbation to be observed. We must face the possibility that such a subtractive approach will never be able to reveal the way in which nature and nurture interact in normal circumstances.
- An alternative to the standard subtractive method of genetic perturbations would be a synthetic approach in which living systems would be constructed ab initio from their molecular elements. It is now clear that most of the DNA in an organism is not contained in genes in the usual sense.
- 98–99 percent of the DNA is not a code for a sequence of amino acids that will be assembled into long chains that will fold up to become the proteins that are essential to the formation of organisms; yet that nongenic DNA is transmitted faithfully from generation to generation just like the genic DNA.

May

2011

It’s Even Less in Your Genes by Richard C. Lewontin | The New York Review of Books

www.nybooks.com/...its-even-less-your-genes

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Genetic Nature Nurture Diversity

One of the complications is that the effective environment is defined by the life activities of the organism itself.
Thus, as organisms evolve, their environments necessarily evolve with them. Although classic Darwinism is framed by referring to organisms adapting to environments, the actual process of evolution involves the creation of new “ecological niches” as new life forms come into existence. Part of the ecological niche of an earthworm is the tunnel excavated by the worm and part of the ecological niche of a tree is the assemblage of fungi associated with the tree’s root system that provide it with nutrients.
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- The vulgarization of Darwinism that sees the “struggle for existence” as nothing but the competition for some environmental resource in short supply ignores the large body of evidence about the actual complexity of the relationship between organisms and their resources. First, despite the standard models created by ecologists in which survivorship decreases with increasing population density, the survival of individuals in a population is often greatest not when their “competitors” are at their lowest density but at an intermediate one. That is because organisms are involved not only in the consumption of resources, but in their creation as well. For example, in fruit flies, which live on yeast, the worm-like immature stages of the fly tunnel into rotting fruit, creating more surface on which the yeast can grow, so that, up to a point, the more larvae, the greater the amount of food available. Fruit flies are not only consumers but also farmers.
- presence in close proximity of individual organisms that are genetically different can increase the growth rate of a given type, presumably since they exude growth-promoting substances into the soil. If a rice plant of a particular type is planted so that it is surrounded by rice plants of a different type, it will give a higher yield than if surrounded by its own type. This phenomenon, known for more than a half-century, is the basis of a common practice of mixed-variety rice cultivation in China, and mixed-crop planting has become a method used by practitioners of organic agriculture.
- , the distinction between organisms and their environments remains deeply embedded in our consciousness. Partly this is due to the inertia of educational institutions and materials
- But the problem is deeper than simply intellectual inertia. It goes back, ultimately, to the unconsidered differentiations we make—at every moment when we distinguish among objects—between those in the foreground of our consciousness and the background places in which the objects happen to be situated. Moreover, this distinction creates a hierarchy of objects. We are conscious not only of the skin that encloses and defines the object, but of bits and pieces of that object, each of which must have its own “skin.” That is the problem of anatomization. A car has a motor and brakes and a transmission and an outer body that, at appropriate moments, become separate objects of our consciousness, objects that at least some knowledgeable person recognizes as coherent entities.
- Evelyn Fox Keller sees “The Mirage of a Space Between Nature and Nurture” as a consequence of our false division of the world into living objects without sufficient consideration of the external milieu in which they are embedded, since organisms help create effective environments through their own life activities.
- The central point of her analysis has been that gender itself (as opposed to sex) is socially constructed, and that construction has influenced the development of science:
  If there is a single point on which all feminist scholarship…has converged, it is the importance of recognizing the social construction of gender…. All of my work on gender and science proceeds from this basic recognition. My endeavor has been to call attention to the ways in which the social construction of a binary opposition between “masculine” and “feminine” has influenced the social construction of science.
- major critical concern of Fox Keller’s present book is the widespread attempt to partition in some quantitative way the contribution made to human variation by differences in biological inheritance, that is, differences in genes, as opposed to differences in life experience. She wants to make clear a distinction between analyzing the relative strength of the causes of variation among individuals and groups, an analysis that is coherent in principle, and simply assigning the relative contributions of biological and environmental causes to the value of some character in an individual
- It is, for example, all very well to say that genetic variation is responsible for 76 percent of the observed variation in adult height among American women while the remaining 24 percent is a consequence of differences in nutrition. The implication is that if all variation in nutrition were abolished then 24 percent of the observed height variation among individuals in the population in the next generation would disappear. To say, however, that 76 percent of Evelyn Fox Keller’s height was caused by her genes and 24 percent by her nutrition does not make sense. The nonsensical implication of trying to partition the causes of her individual height would be that if she never ate anything she would still be three quarters as tall as she is.
- In fact, Keller is too optimistic about the assignment of causes of variation even when considering variation in a population. As she herself notes parenthetically, the assignment of relative proportions of population variation to different causes in a population depends on there being no specific interaction between the causes.
- Keller’s rather casual treatment of the interaction between causal factors in the case of the drummers, despite her very great sophistication in analyzing the meaning of variation, is a symptom of a fault that is deeply embedded in the analytic training and thinking of both natural and social scientists. If there are several variable factors influencing some phenomenon, how are we to assign the relative importance to each in determining total variation? Let us take an extreme example. Suppose that we plant seeds of each of two different varieties of corn in two different locations with the following results measured in bushels of corn produced (see Table 1).
  
  There are differences between the varieties in their yield from location to location and there are differences between locations from variety to variety. So, both variety and location matter. But there is no average variation between locations when averaged over varieties or between varieties when averaged over locations. Just by knowing the variation in yield associated with location and variety separately does not tell us which factor is the more important source of variation; nor do the facts of location and variety exhaust the description of that variation.

Aug

2010

Transcending the Nature/Nurture Debate » Sociological Images

TRANSCENDING THE NATURE/NURTURE DEBATE

thesocietypages.org/...renurture-debate-fallons-brain

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Nature Nurture Polarisation

While the nature/nurture debate rages in the mass media, most scholars reject it altogether. Instead, social scientists and biologists alike recognize that our behavior and psychology is the result of an interaction between nature and nurture
James Fallon, a neuroscientist specializing in sociopaths, had been scanning the brains of murderers for 20 years. His research had demonstrated that sociopath brains have a distinct appearance: dark patches in the orbital cortex, the part of the brain responsible for moral thinking and controlling impulses.
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- At a family gathering one day, Fallon’s mom mentions that there were some pretty violent types in Fallon’s own family history (it apparently didn’t come up anytime in the previous 20 years !!!) and, so, he investigates. It turns out that there were eight proven and alleged murders in his ancestral line, including Lizzy Borden, one of the most famous murderers in history. Because Fallon knows that the atypical neurology associated with sociopaths runs in families, he decided to scan the brains of all his family members. No one had the dark patches.
  
  Except him. Fallon had the dark patches. In fact, that brain on the right: that’s him.
  
  Not only did he have the neurology of a typical sociopath, he also carried a genetic determinant known to be associated with extreme violence.
  
  Fallon doesn’t have the answer to why he’s not a sociopath, but scientists think that a person needs to have some sort of experiential trigger, like abuse as a child, in addition to a biological predisposition.
  
  Significantly, [Fallon] says this journey through his brain has changed the way he thinks about nature and nurture. He once believed that genes and brain function could determine everything about us. But now he thinks his childhood [and his awesome mom] may have made all the difference.