Holding a Mirror to Their Natures

David Levine, New York Times, August 26, 2014

When twins have similar personalities, is it mainly because they share so much genetic material or because their physical resemblance makes other people treat them alike?

Most researchers believe the former, but the proposition has been hard to prove. So Nancy L. Segal, a psychologist who directs the Twin Studies Center at California State University, Fullerton, decided to test it–and enlisted an unlikely ally.

He is François Brunelle, a photographer in Montreal who takes pictures of pairs of people who look alike but are not twins.

Dr. Segal was sent to Mr. Brunelle’s website by a graduate student who knew of her research with twins. When she saw the photographs, she realized that the unrelated look-alikes would be ideal study subjects: She could compare their similarities and differences to those of actual twins.

“I reasoned that if personality resides in the face,” she said, “then unrelated look-alikes should be as similar in behavior as identical twins reared apart. Alternatively, if personality traits are influenced by genetic factors, then unrelated look-alikes should show negligible personality similarity.”


For Dr. Segal’s initial study, she asked Mr. Brunelle to send questionnaires to some of his subjects, and she received completed forms from 23 pairs of unrelated look-alikes. The questionnaires yield a score based on five personality measures: stability, openness, extroversion, agreeableness and conscientiousness. The participants also took the Rosenberg Self-Esteem Scale, a widely used measure in social science research.

As she expected, the unrelated look-alikes showed little similarity in either personality or self-esteem. By contrast, twins–especially identical twins–score similarly on both scales, suggesting that the likeness is largely because of genetics. Her results were published in the journal Personality and Individual Differences.

For a second study, she teamed with a skeptic, Ulrich Ettinger, a psychologist at the University of Bonn in Germany who had heard about the look-alike project during a postdoctorate at the University of Montreal.

“I thought that if two people looked alike, they would have similar personality traits because people would treat them the same,” he said. “For example, I thought men who looked alike and were tall and handsome would probably be extroverts.”

Their analysis was consistent with the findings of Dr. Segal’s first study: Personality traits do not appear to be influenced by the way people are treated because of appearance. Moreover, they found, there appears to be no special bond between look-alikes.



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  • E_Pluribus_Pluribus

    Bravo, Nancy L. Segal!
    Historical “trivia” question: Who first anticipated the importance of twin studies for sorting out the effects of environment and heredity?
    [Charles Darwin’s’ first cousin, Francis Galton. Quoting Nicholas Wade’s A Troublesome Inheritance: Genes, Race and Human History, pp25-26:
    In addition to coining the terms “eugenics” and “nature versus nurture, “Galton . . . invented several basic statistical techniques, such as the concepts of correlation, regression and standard deviation. He anticipated human behavior genetics by using twins to sort the influence of nature and nurture. He devised the classification scheme still used in fingerprint identification. He drew the first weather map….”

    • Pro_Whitey

      All that achievement, and yet Dana Milbank of the Washington Post would still accuse him of having tired blood and needing an injection of diversity.

  • Adolf Verloc

    Good study. Along with the Minnesota Twin Family Study, it pretty well puts the nails in the coffin of “nurture-only.”

  • TruthBeTold

    I’m not sure what to take from this.

    I don’t believe people who look alike act alike because people treat them in a similar way. Personalities are developed very early with parents and when most kids look similar. Real facial differences appear after a personality would be formed.

    Can this research be seen as racist or anti-racist?

    • OHDeutscheKlezmerRebel

      This refutes anti-racist attempts to allege that Blacks act so poorly due to the way Whites treat them. It bolsters what I already firmly believed from observing people, that much of our personalities stem from genetics. This, of course, leads to the conclusion that most of the behavioral differences in race an observant person notices are the result of genetics. Negroes will be Negroes.

    • “Personalities are developed very early with parents and when most kids look similar.”

      I’m not even entirely sure what you meant by this, but no. The personality is only subtly nudged, if influenced at all, by outside factors. Which you are, how you act, etc, comes from your genes, and it’s just that simple, what this study disproves is that your environment, ie:”nurture” determines who you are, your behaviour, social status, etc. You can have certain sets of values, a moral compass installed buyout patents, they can guide you, but who you are is who you are.

      A serial killer, or sociopath, isn’t “raised” to be a killer, or be a sociopath, he’s born as such.

      The same way a black isn’t “raised” or influenced by “microaggressions” to be a borderline retarded murderous thug, he’s merely born that way.

      • TruthBeTold

        I’m a firm believer in genetics.

        However, how a child is reared makes a difference.

        Look at the process of ‘Learned Helplessness’. Even a child who was born a genius would have difficulty overcoming the psychological damage of bad parenting.

        The opposite of this might be the ‘Self-esteem’ movement where parents and teacher convince average and low IQ kids that they’re geniuses or they could be anything if they just believe.

        I’m not trying to give blacks an excuse because I see their failure as universal (the same failures can be found in a neighborhood in America or a nation in Africa) and therefore genetically based.

  • Ghost of Galton

    Interesting; here’s what I take away from this in terms of race: since the appearance of a person and others’ ensuing reactions to same do NOT appreciably influence personality, we can conclude that overwhelming black anger, psychopathy, criminality, etc., is NOT due to the “lingering effects” of “skin-deep” discrimination, but rather their own unfortunate genetic endowment. QED

  • During the heyday of Hollywood every big star had a stand-in, someone who looked like him or her and could thus double in long shots and rehearsals for the star. No stand-in that I’m aware of ever became famous on their own. So, we have more proof that merely resembling someone else does not result in similar outcomes.

  • Luca

    Part of the Minnesota Twins Study involved identical twins separated at birth. The resulting similarities were mind-boggling to the point of disbelief when the twins were reunited and compared. Genetics accounts for about 75% of who we are and how we react to our environment.

    • Kenner

      Late eighties and early nineties, a popular documentary based on the Twins Study was run during every fundraiser on PBS.
      Someone must’ve nudged them, and pointed out the implications for race.
      It vanished, and I’ve never been able to find a copy of it anywhere.

    • SentryattheGate

      Yep, I remember some of the results; these separated twins sometimes even chose the same car & choice of clothing style, had wives that looked similar, same/similar occupations, same number of kids etc!

    • Ike Eichenberg

      As was confirmed in the Minnesota Trans-racial adoption study where the academics in charge were shocked to find out that a black kid raised in an affluent and White home was still a full standard deviation behind in IQ than an adopted White kid in the same environment.

      You can remove the White privilege from the White kid, but you can’t install the White privilege in a black kid.

      However I would not be surprised to find out it was closer to 90% barring extreme childhood trauma.

  • tancred guiscard

    That was in the new york times? Holy toledo, Batman!

  • humura

    As I recall, there was fierce opposition to the original Minnesota Twin Studies’ project by the Left. The Left was determined to destroy the notion of nature, and ascribe everything to environment. The Left had already done everything to discredit the twin studies done earlier by the British researcher Cyril Burt, alleging he had fudged his statistics. However, the Minnesota Studies confirmed the stats found years before by Britain’s Burt. The Left will lie and smear to discredit those who report fact, objective science, and not spin results to support the egalitarian myths of the Left.


      All while smugly mocking Christians/Creationist < which I am neither, just to let you know, as if that matters ) as being "Anti-Science" numskulls. For daring to believe in their religion instead of being rational minded people like them, and believing in Science. The hypocrisy liberal's/progressives display on a daily bases is impossible to miss, yet somehow they all miss it. They talk about how stupid Christian's ( never Muslims though, even though they believe in creation too, ever notice that? ) are for questioning the obvious truth of the Scientific evolution of man kind. Even going so far as to call them the modern day Flat Earthers.

      Yet they they deny that evolution has any role to play in explaining why and how the different races, living in different climates in different parts of the world, came into being. Choosing instead to believe their very own socially constructed religion of egalitarianism. Like I said, their hypocrisy is constant, and they either don't even notice it. Or, more likely, they choose to simply ignore it, cementing they themselves as the 21st century's true Flat Earthers!

      • JohnEngelman

        The secular left uses Darwinian evolution as a stick to beat Protestant Fundamentalists with. Then they ignore the Darwinian implications of genetic determinism and race realism. If Charles Darwin was alive today he would be an enthusiastic defender of The Bell Curve, and Charles Murray’s other writings.

        • OHDeutscheKlezmerRebel

          A lot of White Fundamentalists have a tabula rasa, everything is about religion philosophy these days. They will support a White woman Mudsharking, if they think that the Negro is “saved”. They have a realistic view of Islam being a threat to Western culture, but will jump to defend Negroes they think are “saved”, and have an idealized view of church Blacks.

          • Alexandra1973

            Not me.

            I’m a White Fundamentalist. It doesn’t matter if a black truly is a “brother” (pun not really intended) in Christ or not, they still have no business with White women. Or Asian.

            I’m also against bringing them over here. That’s what missionaries are for–go to them, get a church up and running, then go elsewhere.

          • OHDeutscheKlezmerRebel

            We need more open race realist rhetoric in our White churches these days, folks speaking the truth about race, as you and I are doing right here. Miscegenation is against God’s will. There is a scriptural passage, I believe in 1’st Timothy, that admonished us that a mother is to have a child born “in her own likeness”. A Mulatto born to a White woman is absolutely not born in her likeness. This passage is referring specifically to race, and race alone, telling us that the different races of humans are to refrain from intimate relations with each other. Add in that each race originally occupied a distinct continent and remained geographically separated from the other races, and God’s plan is obviously a racially segregated world. There are several of us at my church who see this reality clearly. Pray for a spirit of boldness for us. We hesitate to speak boldly before the congregation about this. We must no longer hesitate.

  • Kenner

    Every time I think I’ve read the latest nuttery out of Academia, I think I’ve heard it all. I had no idea there were ‘scholars’ who actually thought that random lookalikes would have similar personalities because ‘people would treat them the same’.
    I’m beginning to suspect these academics have been inbreeding since the sixties.

    • willbest

      Science isn’t always sexy. Sometimes you are stuck ruling out the obvious. It may seem silly, but it is important work.

  • fatbaby

    Different breeds of animals have different characteristics,this is true in humans but is racist to believe it.

    • OHDeutscheKlezmerRebel

      Exactly. Negroes have a highly different temperament from Whites. Asiatics and AmerIndians do as well, but the massive gap is between Negroes and the rest of us.

      • Terry

        That is because there are two major groups of humans. Those that left Africa and those that stayed.Those that left have Neanderthal genes while Africans don’t.Those that left had to evolve quickly to adapt to their new environment while those in Africa didn’t evolve as fast because the environment remained much the same. That’s my take on it.

        • I think you could more accurately break it down to three groups, those that stayed, those who left and braved the harshest climates for whatever reason, (whites/Asians) and those who left for a more moderate middle ground, which didn’t force their evolution quite as quickly (Indians, mestizos, many island dwelling racial groups)

          • Franklin_Ryckaert

            Having evolved in a cold environment bestows an evolutionary advantage. This is true for the major races but also for the subraces of the major races. For example Indonesians and Chinese belong to the same Mongolian major race but to different subraces. The Chinese evolved in a colder environment in North Asia than the Indonesians. The result is an IQ difference of 11 points.

    • Luca

      It is not racist to believe it. It is realistic to believe it, but only becomes racist when you mention the truth.

  • Peter Connor

    Leftists are, in Prof. Cochran’s words, “liberal creationists.” They like everything about the theory of evolution except the results….

    • Franklin_Ryckaert

      For human beings that is. They don’t care about “discrimination” of animals.

  • Stogumber

    So, there are some psychologists who ask really important questions and do reliable testing to find out what’s the correct answer! With all the junk psychology quoted in the media, I wouldn’t have thought so.

    • OHDeutscheKlezmerRebel

      Barring the politically correct police state that prevents valid questions about race being raised by psychologists, I suspect that many psychologists would raise these questions, and incisive research on behavioral differences amongst the human races would occur. There is no doubt in my mind that differences in brain function would be discovered, especially in the pre-frontal cortex. This would explain why even church Blacks, for example, display the same predatorial nature as other Negroes. Nature always overrides nurture in the end. We see this with animals. Why would humans be any different?

  • Mrfinoni

    This research is significant as it shows that people with inherent ability and talent should be running the show not kowtowing to political correctness and in particular affirmative action.
    Science should be validating that wiser people should be guiding society.

    • OHDeutscheKlezmerRebel

      Definitely!! We should look honestly and incisively at racial differences. Blacks are especially good at sports which offer an appropriate outlet for predatorial aggression (football/basketball). Sports that emphasize developing a precise skill, such as golf and baseball, are dominated by other races. My joke about Tiger Woods is that his Asian side comes out when he plays golf, but his Negro side prevails in interpersonal relations.

  • OHDeutscheKlezmerRebel

    Heck no!! This is an argument for us segregating White ethnostates that separate politically, and maintain racial purity.