Remember "The Children of Men," the P.D. James novel about a dystopian future in which the human race has lost its fertility? I thought about it the other day in a conversation with a guy I'd just met. We were talking about health issues, and I mentioned to him things I'd been hearing recently about the sharp rise in autoimmune disorders, including autism, and speculation among researchers that this might have to do with chemicals in our environment. (That, and elevated stress levels.)
The man said he'd been concerned about dropping fertility, in particular fast-declining sperm count, because two of his three adult sons had been unable to conceive children with their wives. The man said he discovered that there has been a startling decline in male fertility in recent decades. He too speculated that there must be something environmental causing this.
Well, today I started poking around online, and found this:
Multiple interacting factors are likely to contribute to biological fertility challenges, including age, heredity, lifestyle, underlying disease, reproductive tract infections and nutritional status. Demographers have identified voluntary delays in first pregnancy as a major factor. Yet, data from the US Centers for Disease Control and Prevention show that impaired fecundity over the last two decades appears to have increased in all reproductive age groups, but most sharply in younger women (under age 25). These data, together with a growing body of epidemiological literature and many experimental research results showing male and female fertility-related impairment in laboratory animals caused by a wide array of modern chemicals, implicate environmental factors also as possible contributors to human infertility.More:
Specialists can identify proximate (or apparent) cause or risk factors in the male, female or couple in the majority of infertility cases. Within this “explained” category, however, sometimes ultimate (or underlying) causes and mechanisms are understood, but very often they are not.In up to 10% of cases, absolutely no reason for the infertility can be discovered at all – and in a much higher percentage than that, only minor abnormalities that are not severe enough to account for the infertility are identified. These cases are termed “unexplained.” It is biologically plausible that environmental factors could be contributing to (or a component of) ultimate causation of infertility, in both the explained and unexplained case categories.
[snip]
7. A wide range of wildlife populations has been shown to be adversely affected by exposure to endocrine-disrupting contaminants. Well-documented effects include: decreased fertility and increased reproductive tract abnormalities in birds, fish, shellfish and mammals; feminization and demasculinization in male fish, birds, mammals and reptiles; masculinization and defeminization in female fish, birds, mammals and reptiles.
8. Some environmental contaminants at high, occupational exposure levels were shown decades ago to impair human fertility, for example lead and the fumigant dibromochloropropane.These types of exposures, however, are unlikely to explain more than a small fraction of the infertility observed in today’s population. More recently, considerable data support the contention that exposure to certain agricultural pesticides at moderate or environmentally relevant exposure levels are associated with adverse reproductive outcomes in men and women working on or living near farms (male subfertility and sperm damage; menstrual alterations, increased time to pregnancy and spontaneous miscarriage rates).
The "Our Stolen Future" site seems to be a clearinghouse for information related to possible ways environmental chemicals and hormones are disrupting human health. There is evidence that some chemicals work on some people synergistically. Also: I have wondered if there is some connection between rising levels of autoimmune disorders in humans, and the colony collapse disorder killing so many honeybees, which last I heard was an autoimmune deficiency of some sort.
Mind you, I'm not claiming anything here, but rather throwing all this out there to see what any of you may have read or thought about this stuff.
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It seems to me that low fertility rates are highest in highly developed nations. East Indians certainly don't seem to have a problem, except for the weathly few who live a more Western lifestyle. I know plenty of healthy couples who cannot get pregnant.
Karen Brown: I've completely lost what you are talking about, but it's not about my post. My point is a no-brainer: males with sperm counts lower than required to keep up with competitors will soon vanish from the gene pool, unless everyone else restrains their breeding. This is not even debatable.
Jullian, The reason groups like Mennonites and Mormons have expanded is lack of economic competition.
This is so obviously false I hardly know what to say. Or, as you would say, your claim is so preposterous it's hard to ridicule.
Mormons live side-by-side with lots of other religions, sharing the same economic conditions. Many live on both coasts, even in other countries. Yet they consistantly show higher birth rates, no matter where they live. Your theory is bunk.
Economics and breeding: In the US, there is an inverse correlation between economic advantage/eduation and breeding, along all income levels. The only known moderators to this are religion or cultural background, and the latter doesn't last long in modernity without the former.
MDavid, only if the reason for 'low sperm count' is genetic. Otherwise, that guy just bred at a lower rate than normal, and that is all it means.
Unless it is a trait that can be PASSED ON, it has as much bearing on the next generation as, again, cutting off someone's pinky finger.
AND only if they don't breed at replacement rate, which is just two kids.
Neither of which is the slightest bit proven. Last I checked, the low sperm count issue seems to be more environmental than genetic.
Therefore, again, it has no bearing on future generations.
Not breeding alot, being Mennonite, having a low sperm count, none of them are inherited traits. Therefore, they are not going to either overwhelm, or die out.
Again, assuming that breeding a lot is assurance that a particular group within a species won't die out.
If the 'green deer' breed to the point they outrun their food supply,they can very well end up dying out faster than a much lower breeding group.
Where does this idea that having bunches of offspring is always a positive for species survival?
Roaches have offspring in the millions. An elephant might have three in their entire long life.
There's still roaches.. and there's still elephants.
And all but the alpha pair of a wolf pack don't have offspring at all.
There's still wolves, too.
Again, you are talking of subsets of people demonstrating certain behaviors within a species. Traits that aren't even genetic in origin.
Therefore, this has NOTHING to do with evolution.
Chris Vaughan,
I've also read about hormones in the water. Some male fish (trout, I think) are 'girly-men'. And then men drink the water.
What I've seen, anecdotally, is people contracepting during their fertile years, and then failing to conceive when they're older and have been taking the pill for 15 years. Duh. Those subcultures everyone's arguing about (Nigerians, Mormons, Mennonites) aren't contracepting. I bet Catholics who conform to Church teaching on contraceptive, also are more fertile.
I'm not entirely clear on these arguments you're making, folks, but I'm pretty sure fertility, and infertility, have a tendency to be passed along, or not passed along, to offspring, or a lack of offspring. However, medical advances have enabled infertile couples to have more children than Darwinism would allow. Therefore, infertility is now able to be an inherited trait for more of the population. Yes, limit your intake FD&C Yellow #5 or whatever, but don't wig out over it. Women today survive multiple c-sections so we don't die in childbirth, and bear more children who have problems with childbirth, ya know? Or, y'all do. I had all eight no problem, so don't fear for the future. My superior genes will win out in the end! (They're all good-looking and smart, as well as healthy and pro-life, so as long as civilization retains the ability to make glasses, it's a rosy outlook for us.)
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