Genotype, Phenotype, And Norms Of Reaction

by David Mertz
No Copyrot

My previous comment:

"... and will lead, soner or later, if not to the causes of English-speaking, then at the very least to some biological markers which correlate with English-speaking." (nuff said?)

A response:

Not really. Help a stupid interactionist understand the logic of your argument. You're not claiming that my point is merely a tautology, are you? The sentence might be empirically problematic, coz we cannot be absolutely sure that there are any biological causes or correlates with English-speaking. I don't think the same could be said of homosex (and you'd disagree naturally :).

Well... it's like this: English-speaking is entirely environmental. Beyond a few people with dreadful genetic deformities (causing brain damage, or whatever), anyone can learn English. Same goes for any language, obviously. English is even a particularly good example of a language that won't even have any accidental widespread correlations with anything genetic. It might be for Finnish or Khoi-San that the relatively isolated groups which speak them also have some genetic characteristic which is non-causally correlated with speaking that language. But there are native English speakers (to say nothing of non-native) from India, and Hong Kong, and Europe, and Native Americans, and Africans/African-Americans. There are just so many different groups (in terms of breeding communities) which maybe had been isolated for a thousand years, but in the last couple hundred have started speaking English, that there certainly isn't any even accidental correlation between anything genetic and English- speaking.

In a general way, I tend to be an "interactionist" as well. But it must be recognized that some things are entirely genetic, or entirely environmental. I suspect sexual orientation isn't either of these, but if it turns out to be entirely environmental, then your language is no good.

I think it's like this:

Entirely Environmental    Interactional      Entirely Genetic
----------------------    -------------      ----------------
  Language                 Height              Blood type
  Religion                 Weight              Eye color
  etc.                     Skin color          etc.
                           Sexuality (??)

I DO NOT think of these columns as a continuum, however. I think they're just three seperate things. The reason is that people usually make a mistake of thinking the "genetic-ness" of something determines the range of phenotypic possibilities. It does, of course, in a sense... but not at all in the way most people think. The usual conception is something like this (using sexuality as a hypothetical, and that old canard about "domineering mother" as the environmental part mind you, this is a joke for me, it's just so stupid that it's funny to use).


 Kinsey Scale:
    ^ (Genotype A) ^                                 ^ (Genotype B) ^
    |              |                                 |              |
 Domin <-------> Passive                          Domin <-------> Passive
  mom             mom                               mom             mom

You see what I mean. The conception is that each genotype gives a certain range possible phenotypic expression. In the popular conception, something which is "more genetic" gives a narrower range, while something which is "less genetic (more environmental)" gives a wider range of phenotypic possibilities.

A more general, and more accurate picture would look like the below. The example I give is an extreme one to highlight the difference with the popular model... but the idea is that ANY curves are possible for some trait across some range of genotypes. In fact, almost any curves CAN be found for various things (like height of corns in different altitudes, or whatnot):


     |                                                   ____A___A
K    6 B                                                A
I    |  \_B__                                   ___A___/     Genotype A
N    5       \__B__                            A
S    |             \___B___          _____A___/
E    4                     \_B_     A
Y    |                        _\___/
     3                       A  \__B__
S    |                 __A__/         \___B__
C    2                A                      \__B__
A    |          __A__/                             \__B__    Genotype B
L    1         A                                         \__B__
E    |  ___A__/                                                \_B__
     0 A                                                            \
       Passive mom                                    Domineering mom

You see the idea. If genotypes were like this in terms of "norm of sexuality" it would be impossible to say one genotype was more or less homosexual than another, since each would be "more homosexual" in some environments, but less in others. I draw more or less linear functions for each genotype, but any other curve could hypothetically be there also. One curve which is quite common in actual organisms is a normal-type curve, where a phenotype is maximized (or minimized) at a particular environment, but slopes off in both directions from than maximum (minimum). Of course, some genotypes across some environmental variables have more than one maxima/minima.

One important thing to notice is that even where different genotypes, or genotypic groups, each have a bell-curve in distribution, each genotype may reach maximal values higher than the other genotype has in the same environment while both showing the same general pattern of being maximized at an intermediate environment. For example, maybe there are different educational styles (i.e. rote-learning vs. problem-solving), where everyone does the best with a combination of the two. But perhaps different genotypic groups do better at a different point in the middle. If you have a socially dominant style of eduction, it could produce as an "artifact" the effect of giving one genotype higher average scores. However, if the socially dominant education style were to change slightly, it might favor the other group. The picture might look like:

Norm of Reaction Chart

     |           Genotype A     Genotype B
T    6            _________     _________
R    |           /         \   /         \
A    5          /           \ /           \
I    |         /             X             \
T    4        /             / \             \
     |       /             /   \             \
     3      /             /     \             \
S    |     /             /       \             \
C    2    /             /         \             \
A    |   /             /           \             \
L    1  /             /             \____         \
E    | /     ________/                   \_________\________
     0/ ____/                                       \_______\______
       Environment extreme                               Other extreme