Nature, nurture, and evolution:

A discussion of the significance of genetics and evolution for understanding human behavior

Senior Seminar in Neural and Behavioral Sciences
Bryn Mawr and Haverford Colleges, Spring, 2002

Session 5: The Genetics of Sex, Gender, and Mate Preference
Discussion
(Readings and Web Links)


Name:  Rebecca Roth
Username:  rroth@brynmawr.edu
Subject:  The Genetics of Sex, Gender, and Mate Preference
Date:  2002-03-31 15:22:46
Message Id:  1643
Comments:

Dictionaries define 'gender' as basically the equivalent to sex. However, if you would look at the anthropological definition, it would most likely say that gender is a product of culture.

It makes sense that empirical evidence would indicate that females do prefer male traits that would most strongly stimulate their senses. Certain traits and qualities attract certain people. We have heard the saying that "sex sells". We learn about people's preferences in psychology and how certain people find other people attractive because they feel that they can obtain those people. However, I agree with the article on "How Females Choose Their Mates" which said that the benefits and costs of being choosing when selecting a mate differ for different species, in different environments and sometimes at different times of day. People tend to mature as they get older and what they look for in a mate may change. We know if we ask women what the top qualities they look for in a man and men what they look for in a woman, the answers usually differ. We know that some men want someone who is like their mother, while others do not.

Genes and the brain play an important role in human behavior. Science becomes especially hard when emotions are involved. Is your DNA really your destiny? There is complexity of links between genes and human behavior. Behavior in general is very complex. I agree that particular genes might influence personality traits that could in turn influence the relationships and subjective experiences that contribute to the social learning of sexual orientation. I think there are both biological and experiential factors that contribute to sexual orientation. We know that people can grow up in a household with two gay parents and not grow up gay. There probably is some kind of correlation between structure of the AC and sexual orientation, whether or not the size of the INAH 3 nucleus of the hypothalamus correlates as well. However, with LeVay's studies, the homosexual brains he sliced all came from men who had died of AIDS, therefore the cells could have been significantly affected by AIDS or the medication they might have been taking for it. Researchers can sometimes be confused as to what they are studying when they assess sexual orientation in their research. Did LeVay really know what sexual orientation those people really were? People can be one sexual orientation and act another for various reasons. There was not a range. He also did not include lesbians in his study and the sample size was not that large. Did LeVay's studies really prove that anyone was born gay? Are men gay because of a smaller INAH-3, or was their INAH-3 smaller because of the activities they engaged in, their thoughts, or their feelings? Our brains change in response to changes in behavior and the environment.

However, what exactly are all these studies trying to say? Doesn't everyone have a right do what they want with their bodies? There are many studies being done to try and find out what causes someone to be a homosexual. However, is society itself saying that there is something wrong with being gay? If a gay gene is found, would the nature/nurture question finally be answered? Is it genetic? Is it a choice? Is it neither?There was even studies about the size of your index finger and your sexual orientation. What would exactly be done if we did find scientific evidence?

I think the best evidence for a biological (would not necessarily be genetic) basis would come from animal studies. Most studies of the biology of homosexuality are based on the theory that almost everyone is either almost exclusively heterosexual or almost exclusively homosexual.What about being bisexual? Does that even exist according to science? One study can show a strong genetic factor in male homosexuality while other studies can show that identical twins are more likely to both be gay than non-identical twins. This just shows that the nature-nurture debate will likely continue for awhile. Also, another important thing to keep in mind is that genetic influence does not equal complete determinism.


Name:  Huma Rana
Username:  hrana@brynmawr.edu
Subject:  sex/gender/mate
Date:  2002-04-02 04:11:06
Message Id:  1672
Comments:


Like Rebecca, I feel that sex is chromosomally determined either XX or XY with some rare anomalies, but that gender is a social construct. Mate selection can be socially and genetically influenced, but the extent of each seems to be species-dependent. Although studies on guppies have showed that females can engage in rather complex discriminations between male guppies based on color preference, boldness and fitness, and social factors and imitation, it is unlikely that one could decipher similar patterns in female human beings. I do not deny that there may be a genetic or evolutionary draw to certain males, but this "chemistry" is hardly reason enough to pick a mate. I agree that factors such as education and socio-economic status override unconscious signals, but unlike Dr. Ober, I do not see this as a cause for high divorce rates. In fact, I think that making such a leap is somewhat ridiculous. Furthermore, I am not at all convinced by the arguments for MHC/HLA in modern-day mate selection. I would be willing to accept that MHC/odors may have played a role in mate choice pre-civilization (pre-showers and pre-deodorant), but not now. I did not find this to be a particularly valid line of research or one that is worth pursuing.

I do, however, find LeVay's research on the biology of sexual preference to be interesting. I agree with LeVay that this line of research should be carried out for the sake of knowledge rather than to gain social acceptance or to "fix" what some may perceive as being wrong. There is no denying the critical role that hormones play in the development of the brain, the SDN, and in mating behaviors in rodents. Also, LeVay's findings on the differences in the INAH 3 of heterosexual and homosexual men were notable, but do not imply any causation. This study probably raises more questions than it answers. LeVay failed to study many women, homosexual women, bisexuals, closeted gay men, or heterosexual men who had previous homosexual encounters. It seems that the boundaries of human sexuality and sexual preference may be too fuzzy to perform good scientific research on. Even if a genetic influence on sexual preference is found, I imagine that once again it will be "lemonade".


Name:  Elizabeth Olson
Username:  eolson@haverford.edu
Subject:  sex etc.
Date:  2002-04-02 19:50:52
Message Id:  1686
Comments:
As has been repeatedly mentioned before in this forum, 'sex' is 'biological,' and 'gender' is 'cultural.' I think that in addition to this distinction, 'sex' is usually represented as being a binary category: a person can be either male or female, while 'gender' is usually thought of as a more continuous category: a persona can be masculine or feminine, or something in between. I'm not totally convinced about this distinction, though... The rigidity with which the academic community views the concept of 'sex' is a bit perplexing to me. I guess most people use 'sex' to refer to chromosomal sex, with XY denoting 'male' and XX denoting 'female.' But what, then, do you do with the XXY's? the XO's? I think the tendency there is to classify them on the basis of physical characteristics, for example the presence of specific sex organs. However, the opposite (chromosomal) definition of sex is used to classify CAH 'girls' or the androgen insensitive 'boys.' It seems to me that multiple levels of categorization are in operation: categorization based on chromosomes, and categorization based on physical traits... Basically, I'm not convinced that 'sex' is as simple as we tend to make it seem. I guess I would conceptualize 'sex' much as I conceptualize 'gender': as consisting of a continuous distribution, with a male peak at one end and a female peak at the other. I think the only difference is that for sex, the population tends to be much more clustered around the peaks (less variance) than for gender, where the population is more spread out in the middle ground.


In terms of sexual orientation, my opinion on all of the genetic research is basically contained in a brief paragraph at the end of LeVay & Hamer's 1994 article: "A second idea is that the hypothetical gene acts indirectly, through personality or temperament, rather than directly on sexual-object choice. For example, people who are genetically self-reliant might be more likely to acknowledge and act on same-sex feelings than are people who are dependent on the approval of others." In other words, there does seem to be some evidence that there is a genetic link to 'homosexuality' (i.e. the data on Xq28) However, as mentioned in other postings, I think that genetic research in general has a problem in that the level at which the effect is taking place is difficult to determine. Do the genes involved in 'homosexuality' lead to homosexual behavior? to same-sex attraction? to non-conformity/ antiauthoritarianism? At this point I don't think that we have the data to determine that.


As a side note, I was surprised to read the following in Byne's 1994 article: "Regardless of their genetic sex or the nature of their prenatal hormonal exposure, they usually become heterosexual with respect to the sex their parents raise them as, provided the sex assignment is made unambiguously before the age of three." Was this article published before the revelations about the blatant failure of John Money's Bruce/ Brenda/ David Reimer case? Although it's never a great idea to draw global conclusions from a case study, that case, combined with a great deal of other data about the effect of fetal androgens on sex-specific behavior in mice, for example, seems to me to blatantly contradict Byne's notion that gender in intersex babies is infinitely socially malleable.


Name:  caroline
Username:  cridgway@haverford.edu
Subject:  this week
Date:  2002-04-02 23:55:27
Message Id:  1690
Comments:
Sex and gender are whatever you, the individual, want them to be. That is precisely why debates revolving around their particular points of origin or determination, their relative places in biology or society, or their relation to each other, have continued to rage as they have, with no sign of letting up. In fact, increasing genetic know-how has done nothing but add fuel to the existing fire. Going, for now, with the standard division of sex as biological and gender as cultural, the two still seem to bear some resemblance in how they are manifested outwardly. And, excluding momentarily a consideration of the various genetic anomalies acknowledged, one's expressed sex is typically consistent with one's genotype. By extension, gender as a projection of sex would also have a genetic component to factor in. But there are variations to consider, both on a genetic level and in terms of expected behavior patterns. Our difficulty in accepting these instances is related to society's long-standing aversion to granting equal status to what seems different in some crucial way. A person's gender/sex is often the most fundamental, salient feature when it comes to defining that person. There is an overwhelming urge among members of this society to classify and explain, sometimes to the detriment of those subject to these labels. The danger in coming up with definitive reasons for why a person is of a particular sexual/gender orientation has been recognized. Given that stereotypes and discrimination based on those stereotypes already exist, what is to say that the identification of a gay gene won't only exacerbate those biases. From an anecdotal perspective, it seems as though a person's gender/sexual identity is largely fixed and consistent, both within and across individuals. Observations of small children tend to produce clear patterns of behavior between the girls and the boys. Now, whether those patterns are a result of some innate facet of the children or of some parental influence, or the more likely answer that it is a combination of both, is a whole new argument. But it is one worthy of some thought. Sex/genotype and gender/phenotype are typically treated as distinct entities, but isn't it more likely that the they are related, as we have agreed to be the case repeatedly over the course of the semester? As Liz pointed out in her posting, it seems plausible to think that there might be a genetic factor in determining sexual orientation, but that the switch may be subject to the influence of some environmental or other outside force before it settles into the "on" or "off" position. The evolutionary argument that mate selection as we recognize it in terms of the needs of procreation would select against any variations in sexual behavior is compelling on a superficial level. However, when it is noted that evolution is itself a random, imperfect process, some room to move should be allowed. There have always been and will always be plenty of members of a community who do not reproduce for one reason or another, and to this point this has clearly not stood in the way of evolution. Rather, it is more likely that these individuals have found their own important social roles to fill.
Name:  jimmy
Username:  jsteinem@haverford.edu
Subject:  Session 5
Date:  2002-04-03 00:54:29
Message Id:  1691
Comments:
Is an exploration of the genetics of sex/gender/mate choice useful for what? Useful for this class? Useful for homosexuals? Useful for narrow-minded parents who blames themselves for Junior's homosexuality? What are we talking about?
Certainly it seems to be useful for this class. We can look at the neurological mechanisms that eventually somehow lead to a behavior. Discussing this can help us get more of a general understanding of neural and behavioral sciences on the whole. It is an effective exercise to read one article that supports a genetic basis for homosexuality followed by reading an article that is more skeptical of the topic. This is useful because it forces me to think for myself. I cannot just rely on the discussion presented in the articles but instead have to try to assess the data on my own and draw conclusions from there.
The more difficult question is how useful are these studies for the rest of the world. It is less clear how much the world needs this kind of information. I think LeVay had the right idea that these studies are good for the good of scientific knowledge. I do not think that homosexuality needs to be cured. If the mainstream society is able to be more accepting of homosexuality after being more convinced of a biological determination of homosexuality, however, I think that could be very useful. Parents won't blame themselves and people will be les harassed (hopefully) for their homosexuality. But this is not a definite solution. A lot of luck would have to go into this. And still the data is unclear. While most scientists would concede A biological influence, the data does not say for sure what that influence is. The causation is very much in question in these studies. So, I think it is still some time away before the general public is convinced and will start to get rid of the stigma attached to homosexuality and worst of all some people will probably never be convinced and always hold something against homosexuals.
Name:  Mary Schlimme
Username:  Anonymous
Subject:  Sex, gender, and mate choice
Date:  2002-04-03 02:03:00
Message Id:  1693
Comments:
As others have stated, I agree that the distinction between sex and gender is that sex is biologically determined (as XX or XY female or male) and gender is defined as the more flexible characterizations of masculine and feminine (although like Elizabeth I too am confused about how to classify the XXYs, etc.). Therefore, I see gender as something that is more susceptible to the environment and social constructs, while sex is genetically predetermined. I feel that exploring the genetics of sex/gender/mate choice is useful but not in the same sense as we have decided that the exploration of other topics is useful. In other words, it is useful so that we as people can gain a better understanding of how the brain works for our own knowledge, but this exploration is not useful nor beneficial if it is used to find treatments or preventions for gender or mate choices. However, this exploration is certainly beneficial when it changes people's stereotypes about mate choices - in cases like LeVay's example where a religious man who viewed homosexuality as a sin radically changed his views after he had read several scientific papers suggesting biological influences in mate choice. Unfortunately, scientific exploration of the genetics involved in mate choice can also be detrimental, as LeVay stated, in the sense that if mate choice is biological, then people may feel a need to devise "treatments" for mate choices that they deem inappropriate.


I think that there is no clear cut answer in response to the question about the whether there is a genetic influence on sex, gender, and mate choice although some of the articles stated that animal research seems to indicate a possible biological component in mate choice, I am not convinced that the methods employed in these studies necessarily apply to humans as well. Furthermore, several of the studies with humans suggesting a genetic influence on sexual orientation were twin studies, but these researchers failed to compare their data to twins reared apart (with the exception of one study with only 6 participants). The fact that these studies found higher concordance rates among the twins is not completely convincing of the genetic component involved and fails to examine the effects of the environment perhaps monozygotic twins are treated more similarly than fraternal twins and thus the concordance rates for MZ twins was higher. Overall, given the articles, I suspect that there is a strong genetic influence on mate choice, but I remain uncertain about the validity of the animal data as applied to humans (consider the article that discussed how the sexual orientation of rats was determined). As I've stated, it also seems to me that some researchers have almost dismissed the possibility of the role of the environment in gender and mate choice, which seems problematic. I think that while we are certainly growing in our understanding of the influences on gender and mate choice, many more studies are required before we can feel that we have a complete understanding of these influences.


Name:  julia
Username:  jdiepold@haverford.edu
Subject:  week 5
Date:  2002-04-03 02:15:48
Message Id:  1694
Comments:
I think most would agree that sex is a biological definition, while gender is socially defined. mate choice doesn't really have anything to do with sex or gender in my eyes. people are attracted to who they are attracted to. females to males, females to females, males to females, males to males and males or females to both and that's only dealing with the sex category. gender is even more complicated, a biological male who considers himself/herself to be female could choose a male or female mate who considers themselves to be gendered the same or differently than their biological sex. so what is the point of figuring out how all of this fits together? just out of curiosity? i don't think that homosexuality, or bisexuality or any other type of sexuality is an illness as long as the person and their partner(s) are healthy and happy and aren't hurting anyone else. why spend all the money and time researching the genetic basis for something that does not need to be cured. there are certainly many other more devastating diseases and illnesses that research would be much better spent on. however, in reality, although not life threatening this topic has a large impact on society. if a genetic basis for sex/gender/mate choice issues was found, what would happen? parents of nonherterosexual children would no longer be "blamed," but their children might be considered mutants giving concrete grounds for discrimination. however, if genetic basis to nonheterosexual behavior were ruled out, parents would be "blamed" and their children would be expected to be able to "change" back because mate choice is mere that, a controllable choice. in the end, its probably like most characteristics, the environment and the genes interact to make lemonade. i wish i could say that we should just not think about it and let people and ourselves choose whoever male/female sex/gender we wanted to be with, without fear of judgement. however, the tendency to categorize male/female does seem to be innate. it's the first thing we notice about someone one. when we can't figure it out, its unsettling and there is a tendency to keep looking for evidence that would put the ambiguously sexed/gendered person in a category.
Name:  Caitlin Costello
Username:  ccostell@haverford.edu
Subject:  
Date:  2002-04-03 02:56:31
Message Id:  1695
Comments:
In regards to the sex/gender biological/social issue... If you define gender chromosomally, you get a binary distinction, where the presence of a Y chromosome determines maleness. That leads to a bit of trouble with cases like AIS; I would still have to call these XY people women, and many of them don't know they are anything other than normal women until puberty. But aside from this, a chromosomal sex distinction doesn't lend itself to a "continuum" view of sex. I don't think, however, that the chromosomal definition of sex is how we label males and females--certainly not societally (most of us don't actually know whether our chromosomes correspond to our anatomical sex) and even in the scientific community, it is only quite recently that we have been able to identify someone's sex by looking at their chromosomes. Rather it is the external anatomy that, in practical use, defines sex. And this does create a continuum where the lines between male and female are blurry...e.g. how big does it have to be to call the child a boy?

I'm not so sure that gender is socially constructed any more so than sex is. To the extent that when children are born with ambigious genitalia and choices are made about whether to perform surgery and which sex the child should be, society is constructing a sex dichotomy just as much as a gender dichotomy. Most people identify as either males or females, although there is a whole range of masculinity/femininity within these groups. A few identify as somewhere in between...but that doesnt seem so different as how some are somewhere in between the male and female sex. Of course, society has determined what goes into the two gender roles, but as far as there being two, I don't think the societal component of gender is much greater than that of sex. Using a third dimension of masculinity and femininity, which has a more normal distribution, allows people to be either male or female in sex and gender, yet still have an identity falling anywhere on this continuum of masculine/feminine.

I am not terribly convinced by LeVay's data and the rest on biological influences on homosexuality, for all the reasons mentioned in other posts. I've always been intrigued by Bem's Exotic Becomes Erotic theory of homosexual identity formation, where boys who are less aggressive like to play "girl games" and thus associate with girls, thus viewing their own sex as the strange one, and attributing the heightened autonomic reaction to foreign stimuli as sexual attraction (I don't think he was concerned with same-sex attraction in women). I haven't heard much about this theory lately, so maybe it's been pretty much debunked, but I still like it...it seems to correspond to the trendy stress-diathesis explanations of various things. A genetic (or other) predisposition (diathesis) to lower aggression may or may not lead to homosexual identity formation, depending on how the environment reacts/encourages/discourages sex discordant behavior ("stress") and how strong the predisposition is...and it seems that could be a more direct genetic influence on aggression than on same-sex attraction or homosexual behavior.


Name:  hiro :)
Username:  htakahas@haverford.edu
Subject:  
Date:  2002-04-03 11:31:59
Message Id:  1698
Comments:
Byne (1994) mentions that the sexual orientation results from social learning because many children grow up to be heterosexual with respect to the sex assigned by their parents regardless of their genetic sex. however, i disagree that the sexual orientation is just from learning. first of all, these individuals receive gender-appropriate hormonal injections in addition to plastic sugery to maintain normal-appearing genitals and develop gender-appropriate secondary sexual characteristics. (and i use "gender" as "sex" determined by the parents or doctors regardless of their actual genetic "sex".) it is possible that the perinatal hormonal injections alter the brain development in the direction of heterosexual orientation with respect to the given "gender". also, i have seen some examples of homosexuality resulted from "mis-assignment" of the gender. some individuals with an enlarged clitoris but with XX chromosomes were raised as males. however, they confessed that they thought like girls and got attracted to males. in fact, some of them had male partners. there were similar examples of XY males who were raised as girls. these examples may be rare but still show that the sexual orientation cannot be just learned. just with everything else we have discussed so far, i think the sexual orientation results from combination of nature and nurture.

although i find studies on the sexual orientation interesting, i do not see a point in identifying the cause of homosexuality. what do people do if they find out that homosexuality is genetic? or that homosexuality results from pre-adolescent experience? are the studies done so that they can find ways to prevent homosexuality by discovering the cause? i don't like that these scientific studies treat homosexuality as a disorder of some sort. whatever the cause is, i think it is more important that the society will accept homosexuals as one of many differences that individuals have. if the scientific studies can lead the society in such a way, i think they should be continued. but if they stimulate the existing discrimination against homosexuals, i don't think they should be done at all.

I thought I should share about a talk i went to earlier this semester because it relates to this week's topic a little. i can't remember the name of the lecturer or the title of the talk, but it was about social monogamy and sexual polygamy in birds. many birds are socially monogamous, but they actually mate with different partners! this observation came from one study that performed vasectonomy in birds - female birds became pregnant even though their partners had vasectonomy done. since the surgery was carefully performed, the females must have copulated with those males that did not get the surgery. although, having affairs is "wrong" in the human society, the lecturer discussed both positive and negative aspects of sexual polygamy. for males, the advantage seems clear. by mating with multiple females, males can spread more of their offsprings. For females, however, copulating with multiple males does not lead to a bigger number of offsprings because the number of eggs are limited. sexual polygamy seems disadvantageous in females because it increases the risk of STD infection, and if caught by their social monogamous partners, the females may be severly injured or killed by the male. but, there are adavantages, too. mating with different males assure fertility; if the actual partner is infertile, the female cannot produce offsprings without getting fertile sperms from other males. Also, it increases genetic diversity. Moreover, females may be able to receive "better genes" by mating with a cuter/wealthier male than their husband so that their offsprings will have a better chance of producing more and healthier offsprings. in spite of all the advantages of sexual polygamy, birds, like humans, stick to monogamy socially because both parents are needed to raise their offsprings.

do genes play a huge role in mate selection in humans? the study of HLA alleles suggest that they do. however, in humans, there are a lot of environmental factors that drives one's decision. i believe that smell is very important in attraction. but when it comes down to mate selection, humans think about more. personality, wealth, intelligence, family background, and so on. and i also think that mate seletion depends on one's experience with many people or events that affected one's personality development. since i don't think personality is not simply genetic, i think mate selection depends on more than genetics.


Name:  jess
Username:  Anonymous
Subject:  sex/gender
Date:  2002-04-03 23:09:05
Message Id:  1707
Comments:
I too agree that sex is a biological construct, but would add that gender is not only socially and culturally constructed, but also defined by the person themselves. A person may classify him or herself biologically as one sex but identify him or herself with another gender. There's a group of people in India who while they have both sets of sex organs, identify themselves as primarily female, but classify themselves as a third sex challenging most people's ideas of sex as dichotomous (see Freilich, Morris (Ed) Deviance: Anthropologic Perspectives). When bringing mate choice into the discussion the picture gets a lot cloudier. I think it's safe to assume that those who chose mates of the opposite sex (using sex to mean biologically determined and gender to mean socially/culturally/personally determined) would consider their own gender to be the same as their sex. But, then again I'm not so sure. When you run into the case of one who is transgendered, say a person who is biologically male but who identifies herself as female and who is in a relationship with another person who is also biologically male but identifies his gender is male, would you classify that relationship as heterosexual or homosexual? With regard to the research done on flies I found it interesting that the short stalked females didn't desire males with longer stalks. I would not have thought that female preference would have coevolved. Was this simply because there was no evolutionary significance to having longer stalks. Even if runaway selection was in place wouldn't the original preference for longer stalks take precedence. As far as LeVay's study goes I would criticize the fact that he only used homosexual males with AIDS and didn't bother to determine the sexual orientation of his female subjects. I feel that posed serious confounds. Nevertheless I find the research on INAH3 leading us in the right direction but more more controlled studies would provide greater insight.
Name:  Nirupama Kumar
Username:  nkumar@brynmawr.edu
Subject:  sex and stuff
Date:  2002-04-04 00:27:15
Message Id:  1710
Comments:


The article on finches seems most appropriate to answer whether or not there is a relationship between sex, gender and mate choice. Mate choice may also be termed sexual orientation I believe. Sex is determined by genetics and physiology. I disagree that gender is a 'social construct'. I instead think that mate choice/sexual orientation is the real 'social construct' that is defined by intereactions with other individuals around you. Gender simply seems to refer to the morphological traits of sex. The way sexual traits are expressed does seem to be able to be controlled by hormone injection and living arrangement (which also influences hormonal levels, just ask any Mawrtyr). These both seemed to influence mate selection, though sex seemed to take over when placed in a colony environment. What does this mean? Gender and sex both play a role, but it is hard to transcend genetically assigned roles. Research on the differences between heterosexual and homosexual brains was very interesting, showing perhaps a unique difference in homosexual gender.


Sexuality is almost completely tied to natural selection in my mind. The entire point of sexuality is reproduction. Therefore, it seems only natural that we would study the genetics of this process. I think the exploration is very useful in understanding how evolution works and the basics of human behavior as well. Mate selection is a large issue for all of us, and understanding better what makes us do the things we do is beneficial for our self-knowledge. Considering that most literature centers on love and relationship, I think that biology should not ignore this field.


The genetic link to mate selection seems obvious, especially given the sort of selection cascade phenomenon. An individual chooses a mate not only because he has the most desirable characteristics, but also because her progeny will more easily find mates. Thus, desirable traits become entrenched. How else do we determine what is desirable than what are genes pre-dispose us for. There seems to be good evidence that humans are very drawn to certain MHC sites in smells, which correlate to their genes. Other factors, such as imitation play a role as well. But, genetic predisposition to colors for example rules the day when the differences are easily discernible.


Name:  ingrid
Username:  ladybasti@aol.com
Subject:  Skeptical
Date:  2002-04-04 01:31:54
Message Id:  1713
Comments:
I believe that though all of the articles listed are interesting, work that isn't done on living human beings may not be the best way to determine the link between sexual orientation and biology. I think that there are aspects of the human/human mind...whatever makes us us that makes our mating rituals and any sort of natural selection process a bit more complicated than finches. We aren't even sure what people code for or look for in a mate, we don't even know what is considered to be the most evolutionary advantatgeous (example: brains or brawn? for one.)

And just like, say, how we can not test certain aspects of language on some animals I don't think that animal studies on sexual orientation can completely explain the phenomenon. Le Vay's findings are intriguing but there are so many confounds. The disease itself, the fact that the difference could be consiquence not cause, etc.

I just feel like we are So far away from finding anything truly conclusive, if even insightful about the topic. The brain has yeilded few other secrets in other topics that have much more extensive research (the most hopeful I think would be memory). As for whether we should even research this and that controversy: I feel that we should research anything and everything. What we do with the knowledge is a question we should ask when we come to it. I think that's a basic benefit of free will-- choice rather than blind ignorance and inactivity.


Name:  Nirupama Kumar
Username:  nkumar@brynmawr.edu
Subject:  gender
Date:  2002-04-04 10:58:49
Message Id:  1717
Comments:
Just a quick note about gender. I meant to look this up when I posted but I forgot. According to Webster's and American New Heritage Dictionary gender is actually a grammatical classification of words. I suppose that does make it a cultural construct, but a very specific one governing words we use.


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