Study Explains Why Women Miscarry More Males During Tough Times 113
sciencehabit writes In times of trouble, multiple studies have shown, more girls are born than boys. No one knows why, but men need not worry about being overrun by women. An analysis of old church records in Finland has revealed that the boys that are born in stressful times survive better than those born during less challenging periods. The work helps explain why women may have evolved a tendency to abort certain males and could lead to a better understanding of miscarriages.
You are not in control (Score:5, Insightful)
Maybe it needs global climate change for the next step...
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Why is that?
Re:You are not in control (Score:4, Insightful)
Sadly true. While I agree with most of what he says wrt evolution the way he says it really gets up my nose. He doesn't seem to understand that you don't get people on side by calling them idiots and trashing their entire belief system. That just gets their backs up and sends them off in the opposite direction to what you intended.
Re:You are not in control (Score:5, Insightful)
I think he considers belief as part of the problem. It's an emotional attachment to a position that lacks evidence. People who get butthurt over being challenged are the ones with the problem. The problem is that today, the culture increasingly defends people with strong emotional positions and sensitivity at the expense of rationality and learning what is. The censorious policy that backs this is the primary threat to free speech.
The notion of end justified means is also part of the problem. Sure, showering someone with deference may get them on your side but it is for the wrong reasons. This is one of the major issues that shapes modern politics. Science is concerned with truth, regardless of politics.
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It's an emotional attachment to a position
Oh, well its a good thing Dawkins doesnt have one of those.
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He probably does have them. The question is whether he can see through that to the truth, and is willing to.
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Unfortunately like Dawkins you have little understanding of human nature. What may be logically the correct approach falls apart when you start dealing with human beings.
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The fact that we're not perfect is not a reason to avoid striving for perfection. Understanding the mechanism of human nature, with all of its irrational twists, is part of the path to bettering ourselves.
The fact that most people don't even accept that an emotional attachment to a position that lacks evidence is an issue indicates that we don't even understand our own motivations and thought processes very well. It's alright that we're not perfectly logical and our irrational behavior probably benefits us
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The problem is WE, the rational, do not
We like to think that we can win by teaching
We cannot, because the irrational don't want tolerance, they want POWER and will say any lie necessary to win.
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Well, no matter how strongly humans may disagree with it, reality is what it is. In the end, it's adapt or die. Blaming the humans who at least try to understand it as the source of the problem will not make the problem go away.
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There are lots of folks with at least one "emotional attachment to a position that lacks evidence".
Suggest to one of them that their favorite governmental approach to something they care about (take your pick) is counterproductive and actually accomplishes the opposite of what they want, and see what happens. You won't get a request to cite evidence or to explain your reasoning. You'll be informed in quite heated terms that you are a horrible person.
(I'd given an example or three, but I've already been
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That has no bearing on his science. From muslims to feminists, there are plenty of people who would decapitate him, so I think he's quite tolerant considering. Compared to the wealth of super churches and oil funded middle eastern islam, he's a pauper, both in terms of money and arrogance. There's also the wealth behind the left wing super pacs funding modern 'social justice'.
That said, I agree that arrogance has no place in science as it is merely a strongly held emotional belief in one's superior ability
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To be fair, feminists are not talking about the same head when they call for decapitation...
Re:You are not in control (Score:5, Interesting)
Deer will also disproportionately abort male fetuses during harsh winters. Offspring born after hard times are likely to be stunted and inferior. Even if they are disadvantaged, a female offspring is still likely to reproduce. But with males, reproduction is more "winner take all". This is certainly true with deer, where a superior buck will mate with many does. But it is also true with humans, were men are more likely to have either many children or none. So carrying a disadvantaged son to term, when he is likely to be unable to find a mate, is a waste of resources.
I am going to take this a step further (Score:5, Interesting)
Be forewarned, this message ain't gonna be Politically Correct
Babies born under hard times don't grown up to be homosexuals
If we are to survey the demography of various countries there is a clear pattern ... that countries with larger percentage of homosexuals, bisexuals, trans-sexuals, and all that (male or female) tend to be those that are relatively more peaceful, with more plentiful offerings of food, and all that
Not to say that there is an absolute zero percentage of baby born during hard times that grow up to be homosexual ... there are always the exception
Take China, for examples ... during the warring / turbulent years (since the late 1800's to the late 1960's) percentage of Chinese homosexuals were very low
Now? With relative wealth and comfort, new generations that were born into kinder and gentler surroundings are experiencing an increase of the homosexual population
Re:I am going to take this a step further (Score:5, Funny)
So are you saying that more homosexuals are born when societies can afford the expense of pursuing science and the arts?
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Meanwhile, remember to thank Alan Turing for his contributions to the computer you used to post that.
Re:I am going to take this a step further (Score:4, Interesting)
Since you didn't provide any sources, is this just your hypothesis or an actually observed pattern? If the latter, I wonder how the amount of non-heterosexual people can be determined? It's an interesting phenomenon if it's real, but do we know with any certainty if it is? Of course, one's sexual orientation doesn't matter unless I'm going to start a romantical relationship with them.
Re:I am going to take this a step further (Score:4, Insightful)
Since you didn't provide any sources, is this just your hypothesis or an actually observed pattern?
Even if he provided sources, they don't prove his hypothesis. Peaceful, prosperous societies may have more homosexuals, or they just may be more tolerant so more homosexuals come out of the closet and are move visible. The latter seems more likely to me.
Re:I am going to take this a step further (Score:4, Insightful)
Be forewarned, this message ain't gonna be Politically Correct
Or true.
You just described and gave an example of a society in which outward displays of homosexuality was negatively received by society.
Take China, for examples ... during the warring / turbulent years (since the late 1800's to the late 1960's) percentage of Chinese who identified as homosexuals were very low because of the illegality and implications of coming out
Now? With relative wealth and comfort, new generations that were born into kinder and gentler surroundings are experiencing an increase of the homosexual population who come out and openly identify and express themselves as homosexual because of the massive change in how society receives them
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Even though I have nothing against gay people, it sounds more plausible that homosexuality is a byproduct of wealth and prosperity where the overall population does not need to rise as much and is reduced when everyone has to procreate to make humans capable of securing all the economical security.
If homosexuality was a constant regardless of how much we starved or were struck by some disaster and we were facing underpopulation, then the homosexuality would get in the way.
Of course all that assumes that the
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Modern homo sapiens is a species that contains homosexuals, which means that having homosexuals among your number is a survival trait. All the human societies that didn't have homosexuals, or that did but cast them out, well they're not around any more. They got outcompeted by the humans that did have homosexuals.
Re:I am going to take this a step further (Score:4, Insightful)
You could say that about every genetic trait modern humans have. What about short sightedness, then? How about an allergy to peanuts? Are these survival traits, too?
Re:I am going to take this a step further (Score:5, Interesting)
Shortsightedness is certainly an aid to finding a mate :)
Seriously though, the presence of male homosexuals in a tribe gives that tribe an advantage over all its hetero-only neighbors. They're males who aren't competition for breeding partners. Competition for breeding partners is the #1 source of self-destructive crazy in any tribal group, hell just look at Islam.
Re:I am going to take this a step further (Score:4, Insightful)
Why not make them asexual then? Gay relationships can have self-destructive crazy, too.
Gay tendency could be a side effect of other gene that is beneficial (or a combination thereof and/or along with a nurture component). For example, you wouldn't argue that blind spots are a survival trait, would you? And yet eyes without them would be considerably better.
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I read a study done on tribes with homosexuals, what they found was that the homosexual man's grandmother had been a, shall we say, prodigious breeder, creating many progeny. Thus, it was theorized that homosexuality is basically a strong attraction to men that leaked over to men, the trait lives on because in women it is a powerful trait for producing young, and its effect on men is outweighed by that benefit.
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And it means that the tribe has a group of individuals who can contribute all the positive things about being male (strength, endurance, agility etc for hunting and group defence) without the number-one negative thing about being male: fighting with other males over females.
Re:I am going to take this a step further (Score:5, Insightful)
Says someone living in (relative) prosperity... So you want life to be harsh, unforgiving and generally hostile to survival, just so your purpose can become to merely exist and get your next meal before your peers eat it.
Wrap your head around the horrible fact that life has no other inherent meaning than to merely exist. You can live an empty (read: no inherent meaning other than to exist) life and have it be a struggle to survive or you can live an empty life and add all the frills to it that make it meaningful to you.
Either way, life is indifferent to what you choose.
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percentage of Chinese who identified as homosexuals were very low because of the illegality and implications of coming out
Forgive me, but arent you, like everyone else in this thread, speculating?
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Jesus people, the fetuses are not being "aborted" in an active sense, as much fun as it is to believe that evolution is some magical force making plans for the future of the species.
For whatever reason, females are sturdier (female sperm are slower than male but sturdier, females have stronger immune systems than males, etc). That explains why males are more often "aborted" during times of stress: stress causes miscarriages, but stronger fetuses are more likely to survive stress.
Then for part two. Males
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Doesn't that all make more sense ...
No it doesn't. If a trait provides a reproductive benefit, and it is monotonically marginally beneficial, then life will almost always find a way to evolve it. Just because you can understand the mechanism (frail male fetuses in this case) doesn't mean there is no evolutionary advantage. You are just shifting the question from "why are males more likely to be aborted" to "why are male fetuses more frail". But the answer is the same in either case: Because selectively aborting inferior males provides a
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No it doesn't. If a trait provides a reproductive benefit, and it is monotonically marginally beneficial, then life will almost always find a way to evolve it.
You're basically asserting without evidence that there's an invisible hand of evolution. There's not. Some mutations happen much more frequently than others, and, if a trait can only be expressed with a sequence of very rare mutations, it might take a very, very long time (as in, "will never happen in a trillion trillion years") for evolution to be expected to get there. Others sort of just happen, and not for any real reason or anything, at least as far as we can tell. Evolution will only destroy a mut
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Eh it happens because one male can impregnate many females, therefore ensuring maximum population survivability. Nothing to do with relative toughness, except by accident.
Simple, really.
A superior simpler hypothesis of why this happens (Score:2)
your post and all the other posts here assume that there is some means for the mother deer to tell if she has a weakling in the oven or not, and then also has means to choose to miscarry weaklings.
Here's a less complicated hypothesis that has the same effect: Human's and chimps share >99% of their DNA. But an X and a Y chromosome are largely different. A human male baby is more similar to a male chimp than to his own mother. Whereas a human female baby is more simillar to her mother than a female
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I've got another just-so story:
Deer will also disproportionally abort female fetuses during harsh winters. Offspring born after hard times are likely to be stunted and inferior. Even if they are disadvantaged, a male offspring is still more likely to reproduce, because the male reproductive system is simpler and therefore less likely to be affected by fetal malnutrition. So carrying a disadvantaged daughter to term, when she is likely to be less fertile, is a waste of resources.
The implications for reaso
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The selfish gene is an interpretation. "Life as a single process" is another interpretation that returns the same result ("tougher times, let's breed more females to increase potential yield and variation, the few males will sure be able to bang more than one"). And in both case contraception and males turning down free rides with no string attached for philosophical reasons ("Bros before hoes") prove that the selfish gene or the single process life is in control of the organism no more than the citizen is
Selfish gene: highly misunderstood term (Score:5, Interesting)
He goes after the chicken and egg problem. Most people think of the egg as chicken's way of making a new chicken. But it is equally plausible, the chicken is merely the egg's way of making a new egg. We think we use genes to more copies of ourselves. Can we consider the genes are making more copies of themselves using us, the humans as a species, as mere replicating machine or incubator?
The question he poses is, "Are genes our selfish way of making more copies of ourselves? Or we are merely replicating machines under the control of the selfish genes?". He takes half the book to make people understand the question. Then the other half to prove, indeed the genes are in control and we are mere replicators. Some of the genes we have in our bodies have copies living in other species, other genera. Some of them are 100 million years old. The genes as a whole are the selfish ones vis a vis the organisms as a whole. They survive. We don't. We as individuals, we as species, we as genus are dispensable. The genes, as a whole, are selfish compared to the animal bodies they live in. The Selfish Gene. Not gene for selfishness.
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Obviously the story anthropormorphizes things a bit, but the principles aren't wrong. For me one of the eye openers was learning about things like this:
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Some of the genes we have in our bodies have copies living in other species, other genera. Some of them are 100 million years old. The genes as a whole are the selfish ones vis a vis the organisms as a whole. They survive. We don't.
Getting back to chickens and eggs, part of the chicken I ate last night is now living on inside me, where I am a different species. So I'd say it was the chicken's animal body that was the selfish one, I bet the genes are digested by now.
Why are the trolls all up in this thread? (Score:1)
Re:Can't troll worth a shit, so wall of text? (Score:2)
Again, what did I write to make you hate me s
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The trolls are coming to me now? How excitibg. You flooded that thread with pagee of shaggy dog story filler nonsense, and then acted as if you never did anything of the sort. Somewhat robotic
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Re: Can't troll worth a shit, so wall of text? (Score:1)
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Do you mean this post [slashdot.org] where I explained that Jane Q. Public's climate science denial violates conservation of energy? Again, why did that prompt you to accuse me of being a paid oil troll?
That study used data from Finland's Winter War... (Score:4, Informative)
...and one of the other things it found was that pregnant women who found out their loved ones were killed during the Winter War and Continuation War were more likely to have children who exhibited certain psychological conditions and behavioral pathologies.
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Fatherless children have more problems anyway - was this allowed for?
Re: That study used data from Finland's Winter War (Score:4, Informative)
Yes. The data was showing that a traumatic emotional event for a pregnant mother was literally causing neurological effects in the developing fetus.
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Similarly, a study of World War II mothers in Denmark, I believe, found that not just their children, but their grandchildren had lower birth weights. This was attributed to the famine caused by the war (i.e., the invading soldiers had plenty to eat, the local citizens, not so much), but it was surprising that the effects were also felt in the next generation. Things that you wouldn't think have a connection to the fetus really can, sometimes even for multiple generations.
It's the production line (Score:5, Interesting)
Times of stress/trouble usually mean a loss of population. The arithmetic's simple: one woman can bear one child every 9 months to a year, while one man can sire multiple children in that same time. That means that adding female offspring at the expense of male will make it easier to recover the population loss. And of course sacrificing the least resilient male offspring favors the ones that'll survive the longest and sire the most children. The fun question is how the mechanisms that've evolved to make this happen actually work. Figuring that out's going to keep researchers occupied for the next century or two.
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More over, is this behavior found among other mammals? Perhaps this evolutionary trait goes way back in the period of primates?
Re:It's the production line (Score:5, Interesting)
Ungulates can re-absorb a fetus during times of stress and insufficient feed.
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As can lagomorphs.
Re:It's the production line (Score:4, Interesting)
My Father, a sheep farmer, would always be really annoyed if a fox hunt ever approached his land, and would go out and stop them entering his fields. He told me this was because sheep in distress could potentially absorb or abort the lambs under stress caused by all the commotion.
He was also a lecturer in Agricultural Science in UCD. I don't know if this information comes from farming anecdotes, or has a scientific background. Possibly both?
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I don't believe that. Evolution is *competitive*: if one organism can gain an advantage over its fellows, it will do so. If other mothers are pumping out mostly girls, and men are rare, then it makes sense for you to produce boys, because each boy will be able to father a larger number of offspring on the abundant women. Never mind that it's worse for the tribe as a whole - it's better for *your* genes.
(This whole business, about how evolution is always to the benefit of the individual, and only ever inc
Re:It's the production line (Score:4, Informative)
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Natural Selection is an inherently random process that statistically moves forward against environmental barriers. Any competition that exists is against the environment, which can, but does not need to consist of individuals in your species, or any other. Any first-year college evolutionary biology class will try very hard to drive this point home into your head.
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Since everybody else is AC I'll reply here, mostly to agree with you.
The obvious argument to your claim is that if a woman had a gene that caused her to pump out more males in these circumstances, then her progeny would probably become more dominant, favoring this gene and making it more prevalent.
However, this is only true if you look at the local community.
Suppose the group of humans in which this gene is taking over is in competition with another group of humans that does not breed with them, but does co
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It's important not to conflate
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The key flaw with your point, with respect to this study, is that it doesn't match the results, at all. Fewer males were born, but their survival rates were higher, leading to similar sexes ratios as in less stressful times. So not only does the study not agree with your statement, it seems that selective pressure still favors an even mix of the two sexes.
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Except that if the study had found the opposite, that more women were aborted, there would be a worldwide campaign to ease the stresses of pregnant women so as to prevent the further denigration of women.
And your evo explanation would have been just as easy- more males means more options, more protection and higher selectivity for more robust women, leading to stronger offspring overall.
Fact of the matter is weaker males is probably easier explained by the lack of redundancy of the X chromosome.
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"Fact of the matter is weaker males is probably easier explained by the lack of redundancy of the X chromosome."
That's about as factual as the moon being made of green cheese.
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So, we've already proven that:
- Female sperm are sturdier
- Female embryos are sturdier
- Female fetuses are sturdier
- Female children are sturdier (or at least have stronger immune systems).
- Female adults are sturdier (or at least have stronger immune systems).
I'm glad studies like this are done to provide evidence for "no duh" issues, because there are often cases where instinct turns out to be wrong, but how is this at all surprising?
Pregnant women have a traumatic event -> weaker fetuses die. Female
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If females were truly tougher or more resilient than males, shouldn't it have been me who died an untimely death and not my sister?
Here, let me fix that for you ...
If females were truly tougher or more resilient on average than males, shouldn't it have been me who died an untimely death and not my sister?
Averages describe a population. What you're describing is individuals. Variances in individuals in a population allow for both to be true.
It's one of those YMMV things.
But you're right when people continue to suppose that evolution has a "purpose," as if there's some guiding will or something.
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The female does not consciously decide to miscarry any fetus. So some part of the female brain is monitoring the status of a fetus and deciding who can live. Is that part infallible? I would think not, so with modern health care humans can probably do better than that part of the female brain. So maybe some abortion are done because that part of the female brain just failed to miscarry that fetus. There are probably more fetus being miscarried by some part of the female brain than are being aborted by some
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The fun question is how the mechanisms that've evolved to make this happen actually work. Figuring that out's going to keep researchers occupied for the next century or two.
This is just me speculating, but you may have answered the question already:
... the least resilient male offspring ...
Obviously is offspring is less resilient, no special mechanism is necessarily needed. Just the mother being under stress herself (nutrition) may cause the less resilient to "not pull through" in the womb. It is my opinion that the male is the less resilient of the two sexes in any case, illustrated by their lower life expectancy (http://en.wikipedia.org/wiki/Life_expectancy#Gender_differences).
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Obviously is offspring is less resilient, no special mechanism is necessarily needed. Just the mother being under stress herself (nutrition) may cause the less resilient to "not pull through" in the womb.
Correct
It is my opinion that the male is the less resilient of the two sexes in any case, illustrated by their lower life expectancy
While you could possible be correct, the evidence is inconclusive as to whether it's an inherent biological aspect, or simply the effect of more dangerous socio-environmental factors upon the statistical average. It's my opinion that the genders are about evenly resilient, biologically speaking- exceptions being given to things like increased vulnerability to certain cancers due to degradation of Y chromosome among smokers, etc.
I look forward to the political abuse of this. (Score:1)
Someone, somehow, is going to find a way to drag this into the abortion debate. Should be entertaining.
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Someone like you?
biological battleground (Score:2)
I've read that from a biological point of view, there's kind of a war between a woman's body and a fertilized egg, where the egg basically does everything it can to burrow in and hijack her body, and the woman's body does everything it can to thwart it. (This is why so many fertilized eggs don't actually implant, or are miscarried very early). It makes sense if you think about it- pregnancy and childbearing (and rearing) are risky and a huge drain on the individual woman- The effect this has is that only t
Misreading (Score:1)
I misread this as "Study explains why women miscarry more *than* males during tough times."
I've always wondered about this, but alas, this answered a different question.
Study explains nothing (Score:4, Insightful)
This study "explains" nothing.
Such a pattern would provide an evolutionary explanation for such culling. It “might be adaptive,” Lee says.
An "evolutionary explanation" isn't an explanation. WHY do more male fetuses die than female during stressful situations? What is the actual mechanism causing this to happen? The answer to that is an "explanation". Further, given the relatively long time frames involved in human reproduction, how would this trait have evolved to cover such a large percentage of the population when it is only needed during stressful situations?
Maybe males require more resources from the mother as a fetus, or maybe the difference in hormones is the tipping point that causes more male fetuses to die in these situations. But just because it appears to be beneficial in some way in the vast scheme of things does not mean that it exists because it is beneficial evolutionary or was selected in some way.
Saying "we found it is beneficial for less male fetuses to be born during stressful situations" does not mean "less males are born because it is beneficial during stressful situations".
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Shhh -- "Evolution" is the modern biologist's way of saying "Zeus did it!" -- but don't let them hear you say it.
It's seriously stunted biological study for the last 100 years.
MinuteEarth video covered this (Score:1)