Gene Expression

This is the shape of things to come for mankind is an article which claims that “Variations in skin colouring are expected to be smoothed out, with most humans moving towards a brown tone.” The source of this is an evolutionary psychologist, Dr. Oliver Curry, but, it seems to me that Dr. Curry is passing off what he read in science fiction as science. Genetics is not blending. I have posted on skin color enough to make clear why humans won’t turn uniformly as beautifully brown as some privileged people! A small number of loci (4-5) control skin color variation, and though random mating can reduce the multi-modality (so “peaks” of light and dark skin may diminish) the variation will be maintained beacuse genetic information is not destroyed, and the alleles which result in dark and light skin will still remain extant in the genetic background. So perhaps all the rest about 6′ 6″ males and mega-cocks might be viewed with some caution (correlated response anyone?).

Update: Wilkins offers his Australian dollar (i.e., 2 American cents).

Comments

  1. #2 Agnostic
    October 17, 2006

    1. In general, increasing “K” in NK models of adaptive landscapes results in more ruggedness, not more uniformity.

    2. The force so strong that most people believe it responsible for sexual reproduction — pathogen pressure — will not go away in 1000 years or 100,000 years. Keeping them out isn’t like keeping the sun off your back: bugs are engaged in an arms race. This will also continue to vary across geographical regions.

  2. #3 pough
    October 17, 2006

    What a silly article. It doesn’t seem like he’s taken reality into consideration. I wonder if this is a hoax like the “last blonde on earth” story. He has a pretty good hoax name, too!

  3. #4 Agnostic
    October 17, 2006

    And 3. Social situations can change a lot in a short time. Who in 200 AD would’ve guessed how smart the Ashkenazim would become?

  4. #5 razib
    October 17, 2006

    What a silly article. It doesn’t seem like he’s taken reality into consideration. I wonder if this is a hoax like the “last blonde on earth” story. He has a pretty good hoax name, too!

    that was my first thought, but the institute is legit. if it is a hoax they’re using his name (also, this is a spin off of some documentary).

  5. #6 John McKay
    October 17, 2006

    Wow. I can’t believe the coffee colored children of the future myth is still around. I remember being told that one back when they were promising us jet packs, a cure for the common cold, and a three day work week for the twenty-first century.

  6. #7 pconroy
    October 17, 2006

    …ape-like worker class.< \i>

    I think the whole piece is far fetched, but the above phrase is just plain wrong!!!

    There will be absolutely no need for a worker class – especially if by that he envisions today’s typical blue-collar workers – as they won’t be needed… we’ll have ROBOTS!!!

    The robot scenario will unfold in the next few decades, with Japan leading the charge…

  7. #8 Mesk
    October 17, 2006

    The species split idea is interesting (albeit unoriginal, as Mustafa points out). Combine assortative mating for SES/IQ (I assume this exists, perhaps razib could comment) with genetic enhancement available only to the rich, and you may just have all the ingredients for speciation, given sufficient time.

    Of course, this only applies if the rich/poor divide remains stable over a long enough period of time, which is an open question.

  8. #9 John Monfries
    October 17, 2006

    Hang on a minute – give credit where it’s due.

    The great H G Wells was the first to portray in science fiction, in the “Time Machine”, the division of humanity into two castes – the beautiful, feckless, above-ground Eloi, and the horrible below-ground caste (damn, forgotten the name – Morgons?) who preyed on them. This no doubt was his forecast of the possible logical long-term result of the English class system. Where are Rod Taylor and Guy Pearce when you need them?

  9. #10 Karl
    October 17, 2006

    I don’t get it. first you say “Genetics is not blending”, then you say “”peaks” of light and dark skin may diminish”.
    I understand that genes (or alleles) are involved and that they behave digitally rather than analog-ly so the dark, or light, skin alleles will never go away. But as the graph in your previous article shows, when a “black” and a “white” mate, 2/3 of the offspring will have from 40 to 60 units of color and will be “tan” or “brown”. If this behavior persists, or increases, won’t there be more and more “tan” people. And isn’t this what this: “Variations in skin colouring are expected to be smoothed out, with most humans moving towards a brown tone.” means? What am I missing?

  10. #11 razib
    October 17, 2006

    “Variations in skin colouring are expected to be smoothed out, with most humans moving towards a brown tone.” means? What am I missing?

    two points. first, many of the comments/links around the blogosphere neglect the importance of variance and suggest that everyone will become brown. e.g., one day we’ll all be brown. i have checked the referrals and multiple links on message boards have pointed to my post specifically to refute the claim that all variation will be removed. secondly, though less importantly, the very assortative mating that curry alludes too will likely maintain skin color multi-modality. this seems to be what happened in brazil as light skinned and dark skinned mixed-race individuals paired off selectively so that light and dark alleles resegregated into two demes. see here.

  11. #12 Karl
    October 18, 2006

    So you are saying that although my analysis is correct: B + W = Brown, it will never happen on a global scale. Is that correct?
    If it is, I think that makes you a pessimist and me an optimist about human tolerance. I think that it is self-sustaining. As it becomes more common, as it is doing the US, it will become more tolerable and acceptable and the trend will accelerate. It may never be total, but I think that it will be the norm with blacks and whites being the minority.

  12. #13 razib
    October 18, 2006

    karl,

    B + W = Brown (-/+ deviation)

    and blacks and whites are already a minority on a worldwide scale :)

  13. #14 Alon Levy
    October 18, 2006

    People talk a lot about skin color, but what will become of the double eyelid given sufficient interbreeding?

  14. #15 razib
    October 18, 2006

    but what will become of the double eyelid given sufficient interbreeding?

    i don’t know, it seems ‘additive’ in character. but we always see it in babies, so never fear.

  15. #16 Fly
    October 18, 2006

    Within the next two decades it will become easy to modify skin color and hair characteristics. A person’s skin color may be a fashion statement much as a woman’s hair color is today. Rather than most people being brown, I expect some will opt for attention garnering colors more commonly seen in fruits.

    I’m hopeful that racial group identifiers that energize identity politics will disappear.

  16. #17 jamie
    October 18, 2006

    What is the “double eyelid”?

  17. #18 razib
    October 18, 2006

    this.

  18. #19 Chris
    October 18, 2006

    Of course, this only applies if the rich/poor divide remains stable over a long enough period of time, which is an open question.

    Not particularly. The rich/poor divide is *already* highly unstable. People move from one to the other in a single generation – or even back and forth multiple times in one lifetime. Reproduction between people of different class backgrounds is also quite common.

    Even the most rigidly stratified societies of the past had substantial gene flow between the rich and poor (mostly high-status males and low-status females, with the children having only marginally more status than their mothers, but it’s still gene flow). Because of the universal frequency of inter-class mating in humans, the conditions for sympatric speciation are not met: you would need *preexisting* lack of interfertility before the gene pools of the classes could even start to drift apart.

    On top of that, all those rigidly stratified societies of the past are, well, in the past. Technological advance has broken down social strata around the world and a level of social mobility that would have been shocking in most places 500 years ago is now commonplace. People who grew up on farms can be taken seriously as candidates for senator or president. More and more people are judged by their own achievements and not their grandfathers’. I am not aware of any credible reason to expect this trend to reverse. Rather, the steadily accelerating demand for the competence to understand and effectively use advanced technology will more likely strengthen it and nobody will be allowed to rest on their parents’ laurels.

  19. #20 Agnostic
    October 18, 2006

    I expect some will opt for attention garnering colors more commonly seen in fruits.

    Especially if nerds are doing the R&D — most would love to see a real-life Orion slave girl.

  20. #21 Richard Simons
    October 19, 2006

    With regard to the Black + White = Brown, a black colleague told me that when his wife, very blonde, from a local farming community, became pregnant the nephews and nieces gradually became more and more excited. On the happy day, they rushed in to see the baby but came out really disappointed, complaining it was just brown all over. They expected it to have black and white patches like their Holstein cattle.

  21. #22 razib
    October 19, 2006

    to be explicit, the ‘F1 generation’ will be brown. the the variance around the expectation will be minimal since two very difference genotypes can only create so many combinations. it is the F2s that occur when mixes cross when the variance latent re-emerges.