Bret Weinstein used to teach evolutionary biology

It was a big win for Evergreen College to get rid of him, because he had to have been teaching it badly. This is the kind of obsolete adaptationist garbage he was teaching, and the kind of twisty reasoning he uses.

Let us begin the vivisection.

Foreskin is an evolutionary adaptation.

No, he does not know that. There is no evidence to suggest that it has any significant effect at all, in an evolutionary sense. There is no history of people born without foreskins in any kind of competitive interaction with people with them; there is no evidence of a differential reproductive advantage in any human lineages.

He’s making shit up. This is indicative of a crude adaptationist mindset where everything must have an adaptive effect.

It had a value and may or may not be net -beneficial in the modern environments

What value? Be specific. What change in value in modern environments has occurred?

Circumcision is also an adaptation that may/may-not be net-beneficial in modern times

Loss of a foreskin is not an adaptation — it’s not heritable. It’s a cultural trait. It’s effects are complex: sure, it may be important in establishing a group identity (a cultural phenomenon again!), but it probably has also led to some small number of babies bleeding out. So what if it may or may not be beneficial? It’s a thing. People also get ear piercings, or tattoos, or funny haircuts. Are those adaptations now?

All this adds up to Weinstein’s kicker.

Surgical sex change is not an adaptation. Done in children it’s immoral.

Alex up there hits the nail on the head. Why is one kind of modification (circumcision) adaptive, but another kind (gender affirmation) “immoral”? This is all just bad rationalization by Weinstein. I wonder if he has a sense of shame left any more?


Has nothing to do with preference. Circumcision has stood the test of evolutionary time. If it was simply negative, selection would have eliminated it.

There you have it: if it exists for some length of time, it is good and must have some advantage, or evolution would have eliminated it, because every bad thing is culled by the all-seeing perfect eye of natural selection. Migraines, bad knees, PCOS, religion, hernias, primogeniture, aging, the infield fly rule in baseball, wisdom teeth, vitamin C dependency, and war, all blessed by the flawless filter of evolution, or they wouldn’t exist anymore.

Good god, what a panadaptationist idiot. They really do exist. With bad logic and science like that, you know all he’s doing is signaling fallaciously to his bigoted anti-trans cronies.

But also, I have to wonder: why does he consider evolutionary consequences to be the only thing we consider when doing a thing? I blog because I enjoy it, not because it gives my offspring some advantage. You can like a rainbow or dancing or music or being in the company of friends because it makes you feel good — not everything is derived from some kind of biological calculus.


  1. raven says

    Bret Weinstein is dumb.
    That sums it up and he isn’t worth spending a whole lot of time on.
    He also lies a lot.

    Bret Weinstein lying:

    Surgical sex change is not an adaptation. Done in children it’s immoral.

    We don’t do surgical sex change surgery on children.

    Washington Post: In recent debates over transgender medical care, politicians have made claims that transgender children are undergoing genital surgeries at young ages. Current medical guidelines say children should not undergo gender-affirming genital surgery before they turn 18.

    He also is wrong about Surgical sex change not being an adaptation. It is an adaptation on the individual level for people who want to live their own life in their own way.

  2. hemidactylus says

    I’m unsure of the benefits of the foreskin or its lacking. The “According to some health experts, the foreskin is the floppy disk of the male anatomy, a once-important flap of skin that no longer serves much purpose.” part of the following is at least funny:

    Apt for a joke.

    How would selection have eliminated the cultural practice of circumcision? Am I misreading Weinstein here?

    Cue Game Theory song…

  3. raven says

    PZ Myers:

    But also, I have to wonder: why does he consider evolutionary consequences to be the only thing we consider when doing a thing? I blog because I enjoy it, not because it gives my offspring some advantage. You can like a rainbow or dancing or music or being in the company of friends because it makes you feel good — not everything is derived from some kind of biological calculus.


    PZ sums it up well.
    The vast majority of our day to day behavior and our culture has nothing to do with genes or Darwinian evolution. Same goes for how we organize and run our societies.
    It is a product of being conscious, self aware, thinking beings.

  4. raven says

    Bret Weinstein is just another right wingnut selling hate and lies for money.

    Like Ralph Limpbrain, Jordan Peterson, Ann Coulter, Ken Ham, or any Fox NoNews commentator.

    He has a house and kids and no job after he quite the Evergreen college one.
    We all need money to live on.
    Most of us find honest work that at least contributes something to our society.

  5. Akira MacKenzie says

    As stupid and barbaric as any involuntary genital mutilation is, there are far better arguments against circumcision that doesn’t require the naturalistic fallacy.

  6. bcw bcw says

    goggle knows all the important questions. It suggested:
    “Are Bret and Eric Weinstein related to Harvey?”

  7. raven says

    What percentage of the USA is circumcised?
    Image result for Is circumcision dying out in the USA
    There’s no question that among the world’s wealthy nations, the U.S. stands out when it comes to circumcision. The WHO estimates that the overall male circumcision rate in the states is somewhere between 76 and 92 percent. Most Western European countries, by contrast, have rates less than 20 percent.May 26, 2015

    Americans truly are exceptional — at least when it comes to …

    FWIW, circumcision is in fact, dying out in the world in general and the USA.

    Bret Weinstein would say that it was an adaptation up until recently and is now being selected out of the population.
    Without explaining why it was an adaptation and then it wasn’t.

    The more plausible explanation is that it is a cultural fashion and fashions come and go.
    It is a lot like female genital mutilation and how is that an adaptation and what happens when it dies out?

  8. Akira MacKenzie says

    Oh, and I don’t think any children are being forced by their parents to go through gender confirmation no matter what the Bible-fuckers who get all their news from Alex Jones might say.

  9. Jazzlet says

    Using the same “reasoning” you could justify female genital mutilation despite the fact that it is harmful to those it is performed on. Weinstien is a complete tosspot.

  10. chrislawson says


    Don’t fall for Weinstein’s shell game. In evolutionary theory, an adaptation is a heritable trait that confers a survival advantage in specific environmental conditions. When Weinstein calls circumcision an adaptation, he is misusing the term since (as PZ points out) circumcision is not a heritable trait. That is, evolutionary adaptation is by definition not the same as adapting to the environment by, say, putting on a coat in cold weather.

    If anything, the persistence of foreskins in all human populations is a strong argument that they likely have an adaptive function which circumcision would — pardon the pun — circumvent. (Foreskins are probably only minor and indirect adaptations. That is, it’s not that foreskins themselves are all that adaptive in modern humans as we can see from the lack of measurable reproductive difference between circumcised and uncircumcised men. It’s more likely that the congenital abnormalities that lead to a lack of foreskin also tend to be highly associated with urethral abnormalities that increase the risk of urinary infections.) The complete lack of rigour to Weinstein’s argument is glaring. The fact that he cannot demonstrate the reproductive benefit of foreskins or of not-foreskins means that the entire argument is spurious. Seriously, this is his argument: “We can’t be sure if foreskins or circumcisions are or are not adaptations, therefore transgenderism is not.” And if one is a hard adaptationist like Weinstein, one should conclude that the persistence of transgendered people throughout history is evidence of adaptation.

    All of this egregious argumentation rests on Weinstein’s misuse of the term “adaptation”. Charlie Kaufman wrote a whole movie about the double meaning of the word. If a screenwriter with no science qualifications can get the distinction right, I find it hard to believe that a biologist could make this error honestly.

  11. Larry says

    So, according to Weinstein, circumcision, which results from human actions, is an adaptation that somehow can result in a genetic change. By implication, any type of surgery can lead to analogous changes in the human genome. If so, why then do we still have appendixes?

    Or am I reading too much into this?

  12. ardipithecus says

    Apparently, if humans stopped murdering, raping, torturing etc, the species would be at risk of extinction.

  13. Allison says

    We don’t do surgical sex change surgery on children.

    Oh, but we do.

    On infants, usually newborns, specifically ones who have, in the opinion of the surgeons, “ambiguous” genitals.” A certain number die every year.

    It’s just that we don’t bother to find out their gender identity first, we only find out what gender identity the doctor wants the child to have.

    What is seen as “immoral” is doing sex change surgery based on the patient’s understanding of their gender rather than some doctor’s.

  14. silvrhalide says

    So Bret Weinstein has been teaching Lamarckian evolution all these years?!
    How did he get hired in the first place?
    I guess the college was “evergreen” for him right up to the point where suddenly it wasn’t. Where else was he going to get a job with benefits that would apparently pay him to spout this crap.

  15. tedw says

    I work in the OR in a children’s hospital, and so have some professional knowledge of this subject. Allison @17 is correct that many intersex children are assigned a gender based on the ideas of the parents and/or physicians rather than waiting until the child is old enough to tell everyone what their gender is. This is in large part done because it is thought that it will be harmful to a young child to not have a specified gender when growing up. This is a societal problem, not a medical one. Additionally, there are instances of sex reassignment being performed on children as a result of (wait for it…) botched circumcisions. Google David Reiner, or read this article for examples:

  16. whywhywhy says

    Question for Bret Weinstein:
    Poor use of logic. Is this an evolutionary adaptation?

  17. hemidactylus says

    @21- whywhywhy

    Given the innate tendency to roll with quick gut feels or heuristics first then let some after the fact rationalization play catch up to the nonconscious impulses later…yes???

  18. consciousness razor says

    Don’t fall for Weinstein’s shell game. In evolutionary theory, an adaptation is a heritable trait that confers a survival advantage in specific environmental conditions. When Weinstein calls circumcision an adaptation, he is misusing the term since (as PZ points out) circumcision is not a heritable trait.

    Next up in the shell game: it’s actually the (doctors’) behavior of circumcising babies which is heritable, which is clearly beneficial for their survival and reproduction. Getting a degree and applying for positions to become a doctor who performs such a procedure is also heritable, as is the use of “Dr.” or “M.D.” before or after one’s name, wearing white labcoats, placing old magazines in waiting rooms, having nurses do most of the work for what are ostensibly your patients, receiving large paychecks every month, and so forth. If it were not so, evolution would surely have eliminated these traits long ago on the savannas of Africa.

  19. raven says

    I was aware that they used to do surgical interventions on intersex young children.
    I wasn’t aware that they are still doing that.
    The trend for the last few decades has been to not do early intervention surgery on very young patients who can’t give consent. It has turned out that this sort of surgery is more for the doctor’s and parent’s benefit than the individual patient’s benefit.
    It’s been called the, “Don’t treat when you can cut” approach to medicine.


    Reader Advisory: This report contains graphic descriptions of traumatic experiences, often affecting children.

    Intersex people in the United States are subjected to medical practices that can inflict irreversible physical and psychological harm on them starting in infancy, harms that can last throughout their lives. Many of these procedures are done with the stated aim of making it easier for children to grow up “normal” and integrate more easily into society by helping them conform to a particular sex assignment. The results are often catastrophic, the supposed benefits are largely unproven, and there are generally no urgent health considerations at stake. Procedures that could be delayed until intersex children are old enough to decide whether they want them are instead performed on infants who then have to live with the consequences for a lifetime.

    A young child stands between her parents in their garden, pointing into the distance
    Intersex people are not rare, but they are widely misunderstood. Biology classes often oversimplify a fundamental reality. We are taught that sex is dimorphic: simply male or female. But sex, in reality, is a spectrum—with the majority of humans appearing to exist at one end or the other. In fact, as many as 1.7 percent of babies are different from what is typically called a boy or a girl. The chromosomes, gonads, internal or external genitalia in these children—intersex children—differ from social expectations. Around 1 in 2,000 babies is different enough that doctors may recommend surgical intervention to make the body appear more in line with those expectations.

    Until the 1960s, when intersex children were born, the people around them—parents and doctors—made their best guess and assigned the child a sex. Parents then reared them per social gender norms. Sometimes the intersex people experienced harassment and discrimination as a result of their atypical traits but many lived well-adjusted lives as adults. During the 1960s, however, and based largely on the unproven recommendations of a single prominent psychologist, medical norms in the US changed dramatically. Doctors began recommending surgical solutions to the supposed “problem” of intersex traits.

    In this report, based on interviews with intersex adults, parents of intersex children, and medical practitioners working with intersex people, interACT and Human Rights Watch document the fall-out from that medical paradigm, and the failure of the medical community to regulate itself effectively. As detailed below, there have been changes in practice in recent years, with many doctors now advising against surgery on infants and young children. But even so, surgery continues to be practiced on children with atypical sex characteristics too young to participate in the decision, when those procedures both carry a meaningful risk of harm and can be safely deferred.

    Some intersex traits—such as atypical external genitalia—are apparent at birth. Others—such as gonads or chromosomes that do not match the expectations of the assigned sex—manifest later in life, such as around puberty. Information about intersex traits can be overwhelming. Whether parents are alerted to their child’s intersex traits at birth, puberty, or another point in life, they can struggle with confusing information and advice.

    Healthcare providers are an important source of information and comfort amidst such confusion. But in recent decades, many doctors have defaulted to advising early irreversible surgery on intersex children. These operations include clitoral reduction surgeries—procedures that reduce the size of the clitoris for cosmetic reasons. Such surgery carries the risk of pain, nerve damage, and scarring. Other operations include gonadectomies, or the removal of gonads, which result in the child being forced onto lifelong hormone replacement therapy.

    This history of surgery was also a history of shame and stigmatization. In some cases, doctors instructed parents to conceal the diagnosis and treatment from the child, instilling feelings of shame in parents and children both. Many intersex people did not learn about their conditions until they accessed their medical files as adults—sometimes as late as in their 50s.

  20. bargearse says

    Has nothing to do with preference. Circumcision has stood the test of evolutionary time. If it was simply negative, selection would have eliminated it.

    By this reasoning any form of body modification that’s been around a while is adaptational; Neck elongation, headshaping, teeth filing are still practiced by several groups around the world. How are these any different to circumcision when it comes to adaption? Weinstein really hasn’t thought this through at all.

  21. says

    I agree with “Alex:” it’s obviously special pleading for circumcision. Just like the circumfetishists who insist that circumcision is NOT REPEAT NOT mutilation, nosireebob, even when it’s pointed out to them that it does indeed fit well within the standard description of mutilation. Once all their claims about the alleged medical benefits of circumcision are debunked, special pleading is all they have. And screaming about “bias,” of course…

  22. microraptor says

    And once again we have conservatives focusing on the genitals of children and infants.

  23. indianajones says

    Suppose he is right though, Suppose that evolution is as powerful and as comprehensively applicable in every situation as he says it is. Does he not realize that evolution has led to species death in better than 99% of cases? Down with evolutionary adaption I say! (sarc for that last bit)

  24. Michael Suttkus says

    Ignoring the “for children” lie, I think we can agree that gender change surgery hasn’t “stood the test of time” because it isn’t very old! You can’t say it “hasn’t stood the test of time” until it’s had time and failed, which it hasn’t done yet! If he actually believed his own argument, he’d be saying that we should just let people do these surgeries and see if the technique is still being practiced in 2000 years, that way we’ll know if it’s passed the test of time or not!

    I don’t want to wait. I’m going to find out by sacrificing some animals and reading their entrails, a practice that has lasted for several thousand years! You can’t argue with the test of time!

    Wait, just how much time does it take to determine if something has passed the test of time? I mean, homeopathy is over 200 years old, but is that enough to demonstrate how great it is? Meanwhile, antibiotics are less than 100 years old, so clearly the jury is still out. Computers are only a few decades old, perhaps Weinstein should avoid them until they’ve proven their worth in a century or two.

  25. nomdeplume says

    So, if foreskins have been chopped off in some societies for a couple of thousand years those societies should have lost them, just like chopping the tails off mice for a few generations results in tailless mice….oh, wait….

  26. R. L. Foster says

    I’ll believe that circumcision is evolutionary adaptive when boys begin to be born without foreskins.

    FTR. I’m not circumcised. I can’t speak for anyone but myself, but it’s hard me to imagine what my sex life would be like without that nerve packed little piece of flesh.

  27. anat says

    One of my brothers was born without a foreskin (or with very little of one, not sure exactly). Still had to go through the ceremony because religion/tradition/identity. sigh.

  28. dangerousbeans says

    There’s actually quite a long history of gender confirming surgeries and other medical interventions. Hijra, some pre-christian Mediterranean groups.
    We just have better tech now (although it could be better still…). Using culture to surpass biological limitations is an obvious evolutionarily advantage

  29. DanDare says

    His concept that is passed on:

    If it’s not maladaptive it must be adaptive.

    A more accurate concept:

    Things change a bit and the changes are mostly neither adaptive or maladaptive.