Evolution’s Worst Mistake? How About External Testicles?(undark.org)
undark.org
Evolution’s Worst Mistake? How About External Testicles?
https://undark.org/article/wilo-lents-human-errors/
39 comments
External testicles are interesting because they do seem like pretty terrible "design" by evolution. However, as any man can tell you, the pain associated with getting hit in these all-important reproductive organs is so severe that he will go to great lengths to avoid it and protect them. This makes sense evolutionarily: men protect their fragile but crucial external organs. It's a lesson they only have to learn once!
Also interestingly, it seems that sperm really needs to be cool to operate well. Some of the first advice fertility doctors will give to a man is to wear loose underwear, i.e. let the testicles hang and stay cooler than the rest of your body. Apparently none of our ancestors had success making sperm at body temperature, so we're stuck with these external organs that are optimized to stay cool at the price of being vulnerable.
Also interestingly, it seems that sperm really needs to be cool to operate well. Some of the first advice fertility doctors will give to a man is to wear loose underwear, i.e. let the testicles hang and stay cooler than the rest of your body. Apparently none of our ancestors had success making sperm at body temperature, so we're stuck with these external organs that are optimized to stay cool at the price of being vulnerable.
Definitely appreciate that you put design in quotes - we aren't really designed in the way that most people think about the word.
My understanding is more like things are tried until something sticks. Maybe internal testicles would have been optimal, but external ones were first and simply good enough to stick around.
My understanding is more like things are tried until something sticks. Maybe internal testicles would have been optimal, but external ones were first and simply good enough to stick around.
It’s also possible that there was a different adaptation that happened at the same time that was more important and that external testicles weren’t necessarily good enough to stick around, but rather not bad enough to ditch!
to make a bad CS analogy, imagine 4.5 billion years of grad student code. Each generation does juuust enough work to graduate, makes liberal use of chicken wire and duct tape, JB weld if you're lucky. Source control is for suckers. Mutation is a great design pattern. Globals are obviously the best. Goto is fine. Dependency management is for lesser beings. The code was hard to write, so it should be hard to read. There are no comments and if there were they would lie.
And meta programming. Lots of meta programming.
It's also possible, in a roundabout way, that external testicles are more for display rather than practicality. Sexual selection has a fairly heavy weight on evolution, even if such a trait has some pretty big downsides (male peacocks being a prime example of this).
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That would make total sense if the human mating ritual involved the male impressing the female with the size of his testicles.
How do you know it didn't? Culture changes faster than evolution.
http://mentalfloss.com/article/79897/why-arent-classical-sta...
“Ancient Greece was a highly masculinist culture,” she explained. “They favored ‘small and taut’ genitals, as opposed to big sex organs, to show male self-control in matters of sexuality."
http://mentalfloss.com/article/79897/why-arent-classical-sta...
“Ancient Greece was a highly masculinist culture,” she explained. “They favored ‘small and taut’ genitals, as opposed to big sex organs, to show male self-control in matters of sexuality."
exactly, most of culture changes fast and for there to be a sexually selective pressure on testicles for a long enough time to make a difference, it would surely persist into recorded history. Either human mating practices are cultural and transitive so they would not exert continuous evolutionary pressure, or they are somehow more ingrained and thus could exist long enough to trigger noticeable evolutionary changes.
[deleted]
> the pain associated with getting hit in these all-important reproductive organs is so severe that he will go to great lengths to avoid it and protect them
Too bad we're so soft-headed that we spend our formative years doing our best to hit each other in the testicles as much as possible!
Too bad we're so soft-headed that we spend our formative years doing our best to hit each other in the testicles as much as possible!
I'll leave the technicalities to the better informed posters and post some related thoughts.
Whenever I watch lions on one of the nature channels, I think a male lion looks so majestic and powerful front on but looks as ugly and vulnerable from the back due to its testicles sticking out. When male lions fight, I get this skin crawling fear of lions ending up with torn testicles. Instinctively I cup my own like football players in the wall do.
That said, I think on bipedal animals like humans (but not stooped over primates), external testicles are not only relatively safer, they are also aesthetically good. I mean, imagine a penis sticking out of the abdomen without the testicles like a hook nose. Picture the famous Greek naked statues this way and you shall see how odd and ugly it would have been. (One might argue that humans might have been conditioned to consider this rather cropped anatomy aesthetic but that's a debate not worth having.) I often wonder if this external pair of testicles is analogous to a pair of breasts, acting like a natural jewellery that attracts mates.
There are several 'feature wish list' I have for humans. Such as. Similar to eyelids, having earlids would have helped against loud noise but I guess noise pollution was not rampant during humonoid 1.0. Same with noselids. I would have loved to have regenerating cartilage, at least, if not regenerating organs (liver is a bit odd but not fully so), but I guess humans didn't live long enough to have lifestyle issues due to joint wear and tear. As for external testicles, if not the way things are, the entire unit, including penis, should have been retractable into a pouch but I guess there weren't pool tables during ver 1.0.
This sentence form the article is gold.
> We are evolved to survive and reproduce, but not necessarily to be healthy, comfortable, or happy
Whenever I watch lions on one of the nature channels, I think a male lion looks so majestic and powerful front on but looks as ugly and vulnerable from the back due to its testicles sticking out. When male lions fight, I get this skin crawling fear of lions ending up with torn testicles. Instinctively I cup my own like football players in the wall do.
That said, I think on bipedal animals like humans (but not stooped over primates), external testicles are not only relatively safer, they are also aesthetically good. I mean, imagine a penis sticking out of the abdomen without the testicles like a hook nose. Picture the famous Greek naked statues this way and you shall see how odd and ugly it would have been. (One might argue that humans might have been conditioned to consider this rather cropped anatomy aesthetic but that's a debate not worth having.) I often wonder if this external pair of testicles is analogous to a pair of breasts, acting like a natural jewellery that attracts mates.
There are several 'feature wish list' I have for humans. Such as. Similar to eyelids, having earlids would have helped against loud noise but I guess noise pollution was not rampant during humonoid 1.0. Same with noselids. I would have loved to have regenerating cartilage, at least, if not regenerating organs (liver is a bit odd but not fully so), but I guess humans didn't live long enough to have lifestyle issues due to joint wear and tear. As for external testicles, if not the way things are, the entire unit, including penis, should have been retractable into a pouch but I guess there weren't pool tables during ver 1.0.
This sentence form the article is gold.
> We are evolved to survive and reproduce, but not necessarily to be healthy, comfortable, or happy
> We are evolved to survive and reproduce, but not necessarily to be healthy, comfortable, or happy
This. Unless, we interfere with the fcking evolution and make necessary alterations ourselves.
This. Unless, we interfere with the fcking evolution and make necessary alterations ourselves.
Ha. Compared to evolution's treatment of human female reproduction, you have to be kidding. Giving birth is extremely dangerous and painful. Being pregnant itself takes 9 months and generally to have one only one child who takes 20 years (in modern culture, younger naturally) to be independent. Compare this to other mammals such as dogs/cats, who are pregnant for shorter, have multiple children, they mature within a year, and birth is way more effortless.
The author doesn't actually think this is the worst mistake evolution made. The articles in this series elaborate on ideas that didn't make it into a final book. The author has some gripes with external testicles, but didn't find them important enough or interesting enough to fit the discussion about them into his book, Human Errors.
Also, not all animals have periods:
https://www.quora.com/Why-do-women-have-periods-What-is-the-...
https://www.quora.com/Why-do-women-have-periods-What-is-the-...
The difficulty of childbirth is a human specialization that tradesoff against huge brains.
Nearly all mammals have external testicles
Nearly all mammals have external testicles
The breathing hole and the eating hole being connected is pretty bad, too.
Why? A good part of how something tastes is actually based on the smell. And I f you want to avoid a food that was poisonous, you want as much input as possible. How better to manage that than by forcing air though the same passageway that has the food?
So even if it increases the risk for choking, you reduce the risk for eating something hazardous.
At least, that’s one possible explanation.
So even if it increases the risk for choking, you reduce the risk for eating something hazardous.
At least, that’s one possible explanation.
This doesn't seem plausible to me, and isn't really how smelling works anyway.
It's much safer to smell something before eating it, and much easier to reject it if it smells bad.
It's much safer to smell something before eating it, and much easier to reject it if it smells bad.
To call any evolutionary adaptation a mistake is to assert a natural teleology of evolution (which is being violated in this case by dangling testicles).
Usually, this makes biologists uneasy.
Usually, this makes biologists uneasy.
I understand it's for a laugh but finding proof in the existence or non-existence for the the super natural in nature has always seemed dissatisfying to me.
It's not like evolution evolves towards the ideal, it just evolves away from the deadly. So unless you can show where external testicles will cause a group of people to die off, there's no reason to believe it should have been absorbed into the body. Plus for the species to continue, you don't really need that many males, anyway, so sub-optimal oddities involving men's bodies are likely to be more prevalent as it won't likely kill-off the species.
The initial part of this article sounded a bit handwavy to me: "Evolution could have simply tweaked the parameters of sperm development so the ideal temperature of its enzymatic and cellular processes was the same as the rest of the body’s processes. [...] The fact is that there is no good reason that sperm development has to work best at lower temperatures."
Do we understand enough of the sperm development process to be able to affirm that a higher temperature variant of the process could work better, and that the only reason for the lower temperature one to have won is path dependence?
Do we understand enough of the sperm development process to be able to affirm that a higher temperature variant of the process could work better, and that the only reason for the lower temperature one to have won is path dependence?
External testicles in domesticated animals are essential. Easy to snip off. Ever tried ploughing a field with oxen that haven't been gelded? Not fun. It's also a very convenient way to manage the breeding of livestock, ensuring some control of who breeds with whom.
(It's also convenient to have external easy-to-remove testicles when one wishes to form certain choirs.)
(It's also convenient to have external easy-to-remove testicles when one wishes to form certain choirs.)
I'm always puzzled why similar topics always end up as a fight between so-called scientists who advocate evolution; and religious folk who believe in an "intelligent designer." The thing is, the "intelligent designer" doesn't have to be the creator of everything, that is, "The God." No. Consider a modern Airbus. It was definitely created by some "intelligent designers." But not necessarily God. If future archeologists find "fossils" of planes from the remains of Wright Brothers' planes up to the modern Airbus, the evolutionists of the time would claim that "planes evolved from bicycles." Implying that no intelligent agents were involved. It all happened on its own. Religious folks, on the other hand, would argue that there is intelligent design therefore planes must be created by an all-powerful God! But the truth is that some intermediary, earthly, intelligent agents, called humans, developed the planes. The same is true for human body. We should be asking who are those creators?
Interesting points! In Ancient Aliens documentary, they claim these "intelligent creators" are the so-called ETs (aliens). But regardless of whether that's true or not, one could ask "ok, who created those ETs?" and again, you'd go one level back and should try to find some older intelligent beings who designed our creators, etc., etc.
But this has to stop at some point, because the universe - to the best of my knowledge - is only (!) 13.8 billion years old, thus, some intelligent beings must have appeared some where in the universe long time ago. The question is: "how did THAT happen?" It could be that mere _chance_ resulted in a very early development of intelligent life on a planet in a galaxy far far away. The same process could have helped shape life on the earth too.
Or, maybe there really was an intelligent _being_ in charge of things that designed the whole universe such that exactly a few billion years after the Big Bang, in a specific galaxy and on a specific planet, some certain type of life would appear which would later create other forms of life, and maybe we are created by those people, thus, indirectly, created by that "intelligent being". You may call that "intelligent being" God.
But this has to stop at some point, because the universe - to the best of my knowledge - is only (!) 13.8 billion years old, thus, some intelligent beings must have appeared some where in the universe long time ago. The question is: "how did THAT happen?" It could be that mere _chance_ resulted in a very early development of intelligent life on a planet in a galaxy far far away. The same process could have helped shape life on the earth too.
Or, maybe there really was an intelligent _being_ in charge of things that designed the whole universe such that exactly a few billion years after the Big Bang, in a specific galaxy and on a specific planet, some certain type of life would appear which would later create other forms of life, and maybe we are created by those people, thus, indirectly, created by that "intelligent being". You may call that "intelligent being" God.
> But this has to stop at some point...
That's my point. We don't need to get into infinite recursion because we cannot know as humans the ultimate origin of anything. The best we can do is to try to find out the local and natural intelligent creators acting in nature within the laws of nature. Those are the things we can know. So, for instance, we can ask those questions, as you mention, Did someone come from another world? Is the creator smaller in scale than human body? Is the creator larger in size than the human body? And let's not forget that the human body is a symbiotic organism. It's a combination of different organisms living as symbionts. Which means that they were independent life forms in the infinite depths of time. These are the interesting questions for me. Trying to explain transformations with the word "evolution" explains nothing. It's like saying "sleeping pill will put you to sleep." Nothing is explained.
But I understand that this is a very sensitive topic for many people. These are just my own opinions.
That's my point. We don't need to get into infinite recursion because we cannot know as humans the ultimate origin of anything. The best we can do is to try to find out the local and natural intelligent creators acting in nature within the laws of nature. Those are the things we can know. So, for instance, we can ask those questions, as you mention, Did someone come from another world? Is the creator smaller in scale than human body? Is the creator larger in size than the human body? And let's not forget that the human body is a symbiotic organism. It's a combination of different organisms living as symbionts. Which means that they were independent life forms in the infinite depths of time. These are the interesting questions for me. Trying to explain transformations with the word "evolution" explains nothing. It's like saying "sleeping pill will put you to sleep." Nothing is explained.
But I understand that this is a very sensitive topic for many people. These are just my own opinions.
I think there is a simple way to describe the difference between the "evolution" of things like TVs, and the evolution of living creatures.
With TVs, we see how the outward form stays the same over a long period of time (rectangle, with varying depth), but the inner mechanism is completely different (vacuum tubes, plasma, LEDs, etc.)
With living creatures, we see how the outward form varies wildly (mouse, elephant, dolphin) but the inner mechanisms have remarkable similarities (skeleton, muscles, organs, genetics).
So it may not be helpful to reason by analogy between these two categories of human engineering vs natural evolution when they are fundamentally different.
With TVs, we see how the outward form stays the same over a long period of time (rectangle, with varying depth), but the inner mechanism is completely different (vacuum tubes, plasma, LEDs, etc.)
With living creatures, we see how the outward form varies wildly (mouse, elephant, dolphin) but the inner mechanisms have remarkable similarities (skeleton, muscles, organs, genetics).
So it may not be helpful to reason by analogy between these two categories of human engineering vs natural evolution when they are fundamentally different.
> With TVs, we see how the outward form stays the same over a long period of time (rectangle, with varying depth), but the inner mechanism is completely different (vacuum tubes, plasma, LEDs, etc.)
This is a very good point. I have to admit I haven't thought about it this way. I'm trying to understand the distinction you make between transformations of living organisms and man-made objects.
So you are highlighting the observation that mammals have similar skeletons and muscle structures, similar digestive systems etc.
What does this observation mean? Example: Wa see a remarkable similarity between human and bird skeletons. The difference is topological because differences are in form only. In topology a doughnut and a teacup are the same object. They may look different but they can be transformed into eech other.
Another example: A cat has a tail. Human skeleton does not have a fully developed tail, but the spinal column ends with a tailbone. This is usually interpreted as a "vestigal" tail; meaning that human skeleton once had a tail but humans lost the tail by way of "evolution". For me this reasoning is not justified. To me it is more plausible that the creator(s) or designer(s) of mammals figured how to design different forms from the same formula. So they knew topology. And by tweaking certain terms in their formula (or genes) they could get a cat, a dog or a human. A dog embrio cannot be distinguished from human embrio in early stages.
We can even observe this topological design in the two human species. The reproductive organs of man and woman are exactly the same; they differ only as the way a doughnut differs from a teacup.
The fact that both sexes have the same reproductive organs, but organized in a topologically different form, does not imply that man evolved into woman. Or woman evolved into man. On the contrary, they must have been created separately with each other in mind.
So if different species have similar organs varying only topologically, this does not imply that one "evolved" from the other. Or that they evolved from the same common ancestor. This only implies that the same formula created both of them.
> (mouse, elephant, dolphin)...
Regarding the topic of the creation of new species by evolution, I belong in Lynn Margulis' school of thought. According to Margulis, new species are created by symbiosis and not by speciation by evolution.
I'm against arguing by using the word "evolution" as a cause because this word has so many meanings that it can mean anything and everything.
This is a very good point. I have to admit I haven't thought about it this way. I'm trying to understand the distinction you make between transformations of living organisms and man-made objects.
So you are highlighting the observation that mammals have similar skeletons and muscle structures, similar digestive systems etc.
What does this observation mean? Example: Wa see a remarkable similarity between human and bird skeletons. The difference is topological because differences are in form only. In topology a doughnut and a teacup are the same object. They may look different but they can be transformed into eech other.
Another example: A cat has a tail. Human skeleton does not have a fully developed tail, but the spinal column ends with a tailbone. This is usually interpreted as a "vestigal" tail; meaning that human skeleton once had a tail but humans lost the tail by way of "evolution". For me this reasoning is not justified. To me it is more plausible that the creator(s) or designer(s) of mammals figured how to design different forms from the same formula. So they knew topology. And by tweaking certain terms in their formula (or genes) they could get a cat, a dog or a human. A dog embrio cannot be distinguished from human embrio in early stages.
We can even observe this topological design in the two human species. The reproductive organs of man and woman are exactly the same; they differ only as the way a doughnut differs from a teacup.
The fact that both sexes have the same reproductive organs, but organized in a topologically different form, does not imply that man evolved into woman. Or woman evolved into man. On the contrary, they must have been created separately with each other in mind.
So if different species have similar organs varying only topologically, this does not imply that one "evolved" from the other. Or that they evolved from the same common ancestor. This only implies that the same formula created both of them.
> (mouse, elephant, dolphin)...
Regarding the topic of the creation of new species by evolution, I belong in Lynn Margulis' school of thought. According to Margulis, new species are created by symbiosis and not by speciation by evolution.
I'm against arguing by using the word "evolution" as a cause because this word has so many meanings that it can mean anything and everything.
There are subsets of creationists. One being that all natural beings came directly from the creator with no evolution (typically young earth), and the kind you mention where something was created by design and further evolved.
> There are subsets of creationists...
This is what I don't understand. We don't need to be "creationists", to observe that the letter "A" was designed by an intelligent designer. That an ant colony is designed by ants.
This is what I don't understand. We don't need to be "creationists", to observe that the letter "A" was designed by an intelligent designer. That an ant colony is designed by ants.
I have developed a personal theory that evolution is basically horrible software that has been tested so long it works reliably. It might even be literal when you consider DNA.
And yet, here you are.
Writes someone who has obviously never menstruated
Elephants have internal testicles, which seems proof enough that any utilitarian explanation about why it's necessary or useful is flawed. Many, or most evolution features are just accidents. Anything that "kind of works" is good enough for evolution.
Truest part of the article:
> Far too often we repeat refrains like “Well, it must do something important or natural selection would have eliminated it,” or “Living things are perfectly suited for their habitats,” or “Evolution doesn’t tolerate inefficiency.” We haven’t really moved on from the creationist mindset that expects to see perfection in nature.