Nutty Science Claim: CO2/global warming shrinking men’s testicles

From the correlation is not causation department, and Mother Jones, comes this absurdity:

A new study from researchers in California has reached some astonishing new conclusions. An interdisciplinary team composed of members from physics, physiology, statistics, and atmospheric sciences began with results from a metastudy of sperm concentration in men. 

This study (chart on left) confirmed that sperm concentrations have been declining since the early 70s. At the same time, measurements from the Mauna Loa Observatory show that CO2 concentrations in the atmosphere have been rising during the same period (chart on right):

 After validating a parameterless model based on surprisingly common consumer software packages, the team derived a transformation equation based on τ = 1 at 1973 for the Mauna Loa data:

y =  π +κx, where π = -238 and κ = -ln(11)

As the authors put it, “Our global manhood is being steadily shriveled into effeminancy by our huge and rising emission of carbon dioxide into the atmosphere.


The paper:

Temporal trends in sperm count: a systematic review and meta-regression analysis.

BACKGROUND Reported declines in sperm counts remain controversial today and recent trends are unknown. A definitive meta-analysis is critical given the predictive value of sperm count for fertility, morbidity and mortality. OBJECTIVE AND RATIONALE To provide a systematic review and meta-regression analysis of recent trends in sperm counts as measured by sperm concentration (SC) and total sperm count (TSC), and their modification by fertility and geographic group.

You can correlate just about anything to CO2 and global warming:


86 thoughts on “Nutty Science Claim: CO2/global warming shrinking men’s testicles

    • Er, it’s odd that they did not consider that men may simply be having more sex and thus less sperm build up. Makes sense to me. Just saying.

    • They should haver claimed
      man’s “favorite organ”
      is shrinking from more CO2
      — well, they are getting close,
      but I’m very confident
      they will say “that” someday,
      as I predicted about
      a decade ago.

      You tell men their favorite organ
      is going to shrink, and they’ll
      listen to you — tell them it
      will shrink and
      “be stolen”
      or “fall off”,
      and they’ll do
      anything you say
      to prevent it.

      See WikiPedia for details (really):

      Hopefully this comment
      won’t start a discussion
      on the important topic mentioned,
      or I’ll probably regret posting this
      under my real name,
      when I could have
      used a moniker such as:
      “Englebert Lipshitz”

      • Living in California
        causes the loss
        of one IQ point a year,
        so there is no need
        for Californians
        to smoke pot as a
        “stimulant” to write
        a stupid article
        or study.

    • No it’s true HotScot and it’s all caused by lack of pirates any good Pastafarian knows this. If you don’t know the background google it. It’s probably more an in joke within the physics community as a reminder that correlation does not equal causation something that get lost in pseudoscience where the junk above belongs.

      • That was my thought, too. People publishing jokes like this is could be a sign that skepticism about the global warming bollox is actually widespread in academia.

        • michael hurt

          leftists will believe
          just about anything
          preceded by:
          “Scientists say … ”

          and in the bad old days,
          of O’Bummer,
          they’d believe everything
          preceded by:
          “The Obama Administration announced … ”

          That statement is based
          on my own “experiments”
          with people I know,
          unfortunately almost all leftists.

          “Scientists say there will be almost
          no snow in the winter, twenty years
          from now”, worked every time.

  1. Sounds like this observation might get any young men who are climate deniers to take notice. We are talking serious consequences after all.

  2. OK, the title is a groaner and the conclusion is preposterous. True, men-darling’s testicles need to be cooler than the rest of the body, but there would be approximately zero sperm reduction from air temperatures that we could survive in.
    However, i keep pointing out that not all the CO2 rise is from fossil fuels. Some is from poison-based agriculture killing soil organisms, whose carbon gets oxidized to CO2. That reduces soil fertility. Total leaf cover is way up–but micronutrients–vitamins and minerals–are reduced. It is likely indeed that this has something to do with male (and female) reproductive problems.

    Still, it is known and proven that plastics are messing with males throughout nature. There are also herbicides and other toxins. Many of these things have feminizing effects on everything from fish to frogs, alligators–and people.

    • Poison based agriculture???

      Now that the know-nothing wing has been heard from, can we get back to science.

      • PS: It’s been postulated but there is no science that actually shows that plastics have any such impacts.
        Ditto for herbicides and so on.

        • And the correlation between the contraceptive pill use & pregnancy rates is?????????? It has been “speculated” that sperm counts in younger generations of men & their mothers’ use of the pill could be significant in the long term!

          • If there’s one thing too sacred for a Leftist/Green to even whisper against, it is the Pill. But you are certainly onto something, as well as the estrogen pollution that passes through our sewage treatment processes

    • “There are also herbicides and other toxins. Many of these things have feminizing effects”
      It’s well known that God created the Man first. God then used herbicides and toxins to create the Woman.

  3. Well it’s a long time since they “proved” the rainfall in the West of Scotland is directly related to the number of people riding bicycles in West Africa.

  4. I believe ‘shrinkage’ is probably caused by turning men into soy boys and the feminists bashing toxic masculinity to the point that they don’t want masculinity period. Are you sure this isn’t another hoax paper that a bunch of wise guys tried to see if it could get through peer review?

  5. The MJ article is a spoof. They say so (indirectly) near the bottom of the article. At least, that’s the way I interpret what they say.

    • IMPORTANT NOTE: My readers are mostly liberals, and believe me, I know what you’re thinking. Those are just two straight lines. The fancy Greek letters in the equation just change the slope and offset of one of them. Correlation doesn’t mean causation. And you’ve provided no causal mechanism at all.

      Right. I get it. Now STFU. Do you want to fight climate change or not? If you do, there’s no harm in a little white lie that convinces men their balls are shrinking, is there? If you think about it, it’s one of the few things that might actually get a reaction from conservative white guys. So just go along, OK?

      • After all, we have to exaggerate the consequences to get the public’s attention. Wasn’t that what Dr P Jones sadi more than a decade ago? And it is up to each climate scientist, individually, to determine how far he or she will bend their personal and professional integrity. Think of the children, and the polar bears.

    • I wasn’t sure which makes it a bad one. I mean if your spoof and satire for reaction you need to offend everyone.

  6. It’s the ever increasing chemical coctail folks.
    When you compare dedicated long term organic farmers to the average comparable person buying supermarket stuff, the sperm counts of the “organic” group is way better off. CO2 is just a spurious correlation here. How toxic would CO2 have been on any kind of balls and sperms during evolutionary times. More CO2 means better conditions for organic farming and more viable sperms per volume unit. Go for it.

    • Can you provide a link to the mythical study that you are referencing?
      PS: Have you accounted for any of the hundreds of other potential explanations? Such as those who are willing to pay more for organics are health nuts in general?

      • Hi. Need some days to pick this up. As far as I recall this was a study on Danish organic farmers. I enjoy many a comment here, but some rway off into the dark conservative corner. The world is not as simple and relationships are often not as the simplest rednecks like them to be. More CO2 is good for you, your balls, your sperm’s motility (maybe not relevant when the gene line is developed in the early testicles of a male foetus) but clearly for plant growth and less use of chemicals when farming food items.

    • I am with MarkW people claiming something is what Snake Oil salesman and Con man do.

      Proof or you are a Snake Oil salesman and liar.

  7. Dr. Christine Blasey Ford is going to use this, and her personal measurements of old, white men for her next very important psychology research paper. It will of course be published by the NY Times.

  8. This study (chart on left) confirmed that sperm concentrations have been declining since the early 70s.


    It was also in the early 70s that the teenage and 20-something females began “freely” giving teenage and 20-something male friends and 1st time acquaintances all the sex they desired ….. and then some.

    So iffen researchers had been measuring/counting sperm concentrations during the past 48 years then of course it would/should have been declining simply because the male is not capable of producing great quantities of sperm and semen every 5 to 8 hours every day, ….. day after day for weeks or months at a time. To wit:

    To hear the ex-hippies and Summer of Love enthusiasts tell it, the spring and summer of 1967 in San Francisco changed everything, especially sex.

    At first, this sounds like more of the same generational hagiography from baby boomers that we’ve been subjected to for several decades now. But there is no question that we are still living with the “free love” fallout. Everything from the rise of Viagra to “Girls Gone Wild” and feminist porn, to the sex education debate and the Christian fundamentalist backlash, bears the mark of that bohemian sexual revolution.

    The lingering image of the Summer of Love has been one of bare-breasted flower children making love in patchouli-scented crash pads, sharing their food, their money and their partners.

    The real story is more complex.

    Read more @

  9. Just to be clear, MOTHER JONES is the publication making the absurd causal connection between sperm count and CO2. The study on sperm count itself says nothing about CO2 — it’s just a study about sperm count.

    All ridicule, then, should be directed to MOTHER JONES.

    That publication gives mothers a bad name.

    • There is a piece of New Zealand Urban Myth from the 1950s:
      The NZ Govt Department of Scientific Research supposedly had the testicles of some rams (male sheep) wrapped in a tea cosies during the mating season to see what effect warmer testicles would have.

      A teacosy is a woollen jacket to snugly cover a tea pot to keep its contents warmer by reducing the tea pot’s rate of heat loss. The ewes the treated rams serviced were tracked and number of progeny were compared with those of the previous year. The teacosy treated rams had a lower success rate of impregnation, from which the conclusion was drawn that increasing warmth lowered ram fertility.

      A control experiment using teacosies loaded with ice cubes was not, according to the legend, considered.

      Note: reproductive performance of both rams and ewes in a herd of sheep is closely tracked as it defined which animals were more likely to be culled.

  10. I blame mainly overweighness/obesity, there’s a known mechanism for excess body fat to decrease testosterone. I am slightly suspicious that bisphenol A, in thermal paper and coatings on the inside of many cans, might have something to do with decreased sperm count.

  11. So, I Guess they used the official IPCC proxies for testicle volume corrected for age and ethnicity.

  12. So that’s what happened to me!

    Here I thought it was age and prostate cancer.

    I demand a monthly compensation check from Uncle Sam. /sarc

  13. Yeah righto, shrinking knackers indeed.

    All global warming does for my knackers is make them hang like a turkeys neck, i just wear longer shorts like African blokes with sweaty b0ll0 x wear.

  14. Our global manhood is being steadily shriveled into effeminancy by our huge and rising emission of carbon dioxide into the atmosphere.

    That should make all those people complaining about “toxic masculinity” demand more global warming now.

  15. Well, AlGore needs some excuse since Shrinkage was proven, via Seinfeld, to be caused by Cold Conditions. His less than adequate brass must be due to CO2.

  16. I blame high fructose corn syrup. And possibly fluoridation. Can I get some grant money please?

  17. My lifestyle for the last 50 years has been tailored to testicle size reduction. Same as I have minimised fat in my diet and on my body. A large sperm volume is like a big beer gut, something best to do without. It is the quality of sperm that needs to be measured for correlations.
    Remember the 1970s feminist cry “Assert your rights! Make him sleep in the wet spot.” Again, the aim is to minimise sperm volume, or rather the volume of messy, fatty liquid carrying the sperm.
    Especially so if you are environmentally sensitive and you reject condoms because after one-off use they are thrown away to pollute the oceans, worse than plastic drinking straws and not interchangeable.
    Sperm management is not a hard concept, you just have to work it out between you. Geoff

  18. You’ve all got it wrong:

    The correct causal relationship is between the rise of radical feminist activism and the reduction of sperm count.

    The rise in CO2 caused more women to become feminists, which, in turn, turned off more men, who substituted eating more for pursuing women, which led to increased male obesity, and so on down to the final result of decreasing sperm count.

  19. 1921 USA: 271 men avg. count 100million sperm/ml; half over 100million/ml. 1938 USA:
    200 men avg. 120million/ml; 25% less than 60million/ml. 194? USA: 49 men avg. 145million/ml; range 50-321million/ml. 1950 USA: 100 men avg. 100.7million/ml. 1951 USA: 1,000 men avg. 107million/ml; 44% >100milliom/ml, 24% 20-60million/ml & 5%100million/ml.

    Not exactly sure comparative ages sampled &
    believe men were fertile; the 1951 data pool
    is largest cited. There were reports in a few countries in the 1990’s about approx. 50%
    lower sperm counts even then. I’m not parsing
    age of those tested in different studies.

    If we accept 1951 USA downward trend data then the declining
    sperm count can not be blamed on soy derived
    products estrogenic potential, high fructose corn syrup or plastic compounds. Of course
    these may be relevant now.

    • It was obviously the above-ground nuclear testing that did it.

      Or more men wearing Speedos.

  20. Yes, it’s pathetic.

    But the “believers” in “science” aka pro-“science” aka highly “intelligent” and “educated” people aka “fact” believers aka “rationalists” aka “skeptics” accept that vaccines caused decrease of infectious diseases with much less evidence.

  21. Obviously true! During the last glaciation CO2 was down to 180ppm and men were routinely hunting Woolly mammoth with wooden spears and defending their homes and families against leopards and saber tooth tigers with clubs and stone axes. Now when CO2 is >400ppm how many men have the stones to do that? I’ve never hunted anything more dangerous than a Jack rabbit and used a rifle for that. Masculinity has clearly declined with CO2 increase. /sarc as if you didn’t know.

  22. It is no secret that there are a large number of misandrists that are seeking to eliminate males from this world. These misandrists have openly declared their contempt for men and their desire to rid the world of men. What a better way to avoid the label murder/genocide than to slowly cook the sperm out of males so no new males are born. Misandrist are a extreme danger to all humankind.

  23. No…’s not global warming that is shrinking men’s testicles…it is liberalism that is doing so.

  24. Oh, so now we have to worry about “global warming” shrinking men’s testicles? I thought (((Feminism))) was bad enough!

  25. Note-it is sperm concentration IN men. Implies (what do you expect in California) that the sperm has been delivered in to men.

    Looks like CO2 increases have made them gay.

    At least fertility is simply not an issue.

  26. A new study from researchers in California has reached some astonishing new conclusions….

    Seems to be a post-modern trend, doesn’t it? But then again there’s always bad pseudo news from Colorado, Arizona, and East Anglia too.

  27. The fact that sperm concentrations are declining is interesting. It implies that fertility is falling too but that may not be the case if quality is increased.

    My own pet theory is that the birth control pill is raising the female hormone levels in the environment. As it isn’t well-removed by water treatment plants there is every reason to think that it may have an effect.

    This is a well-reasoned hypothesis with absolutely no evidence for or against it.

  28. “Nutty Science Claim: CO2/global warming shrinking men’s testicles”

    I see what you did there Anthony – best post title of the year (so far).

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