Scientists have traced human tail loss to a short sequence of genetic code(cnn.com)
cnn.com
Scientists have traced human tail loss to a short sequence of genetic code
https://www.cnn.com/2024/03/23/world/humans-tails-genetic-mutation-junk-dna-scn/index.html
245 comments
I believe this suggests that we could CRISPR an embryo to knock-out the offending Alu element in the TBXT gene and the child will develop a tail.
Rarely is human genetics this simple. For ages geneticists thought large swaths of the human genome were "junk" and over time more and more of it has been proven to have a purpose or function, it just wasn't readily apparent for various reasons.
Think of the human genome as sort of the ultimate dependency hell...
Think of the human genome as sort of the ultimate dependency hell...
Nature does not refactor. There's the laryngeal nerve somewhere in the neck of mammals that has to go around a blood vessel. On Giraffes, this runs all the way down the neck, around said blood vessel, than back up, all that just to connect two places in the upper neck that are inches apart. Evolution writes the ultimate spaghetti code.
More info: https://berto-meister.blogspot.com/2011/08/unintelligent-des...
More info: https://berto-meister.blogspot.com/2011/08/unintelligent-des...
Early developmental biology (by “early” I mean early pregnancy) is the shit you Do Not Touch. Each step of development is highly dependent on the previous steps (assuming this bit’s here, that bit’s there, etc.). If you make a change it’s extremely likely to be fatal or have negative consequences like birth defects, and the likelihood of a bad outcome climbs steeply as you move the change earlier and earlier in the process. That’s why pretty much every animal - humans, tigers, whales, lizards - looks the same when they’re a teeny tiny little fetus.
My example is testicles! Testicles begin in the same place as ovaries, which made a lot of sense back when we were coldblooded! Having a pair of balls dangling in a soft pouch between your legs isn’t a strategy you adopt if you can help it. In the alternate timeline where lizard people rose to dominate the earth instead of humans they don’t have “Ouch, I’ve been hit in the balls!” humor.
But the testicles form next to the kidneys early on in the developmental process (and as we’ve established, you don’t fuck with those stages), so they have to migrate south VERY late in the development! Because they SCHLOOP on down after everything else is pretty much in place, it weakens the abdominal wall, which is why men are more prone to certain types of hernias than women are.
My example is testicles! Testicles begin in the same place as ovaries, which made a lot of sense back when we were coldblooded! Having a pair of balls dangling in a soft pouch between your legs isn’t a strategy you adopt if you can help it. In the alternate timeline where lizard people rose to dominate the earth instead of humans they don’t have “Ouch, I’ve been hit in the balls!” humor.
But the testicles form next to the kidneys early on in the developmental process (and as we’ve established, you don’t fuck with those stages), so they have to migrate south VERY late in the development! Because they SCHLOOP on down after everything else is pretty much in place, it weakens the abdominal wall, which is why men are more prone to certain types of hernias than women are.
Nature does not refactor, except when it does as in the case of going from 48 to 46 chromosomes (great apes->humans). Nice write-up and slightly novel hypothesis at: https://molecularcytogenetics.biomedcentral.com/articles/10....
https://youtu.be/cO1a1Ek-HD0?si=H6X6ICZQLbq_s41C
The famous Richard Dawkins video about that (4min long)
The famous Richard Dawkins video about that (4min long)
"Octopus throat runs through brain" and the "blood supply in FRONT of the retina cones n rods" were the other 2 that are often mentioned.
Nature hires a million devs and then kills the project if they do not hit a deadline.Nature mixes it up with sex and creatures hunting one another. There are no chill moments.
God must be a frontend developer.
Or hacked it all together in Perl: https://xkcd.com/224/
He's definitely full stack.
Nature rarely* refactors. Sometimes random mutations refactors, which leads to efficiencies which leads to evolutionary advantages.
If nature doesn't refactor, then why are there so many crabs?
If nature doesn't refactor, then why are there so many crabs?
There still is a lot of non-coding dna in there.
If it didn't fulfil a function, then random mutations and deletions during Meiosis would quite quickly get rid of it. Even if it only serves to support the structure of chromosomes or some similarly arcane purpose that we will only discover in a decade or so, it still has a function.
Yes, the genome-layer is nondeterministic. But there are also more layers that are probably just as nondeterministic, adding more complexity to your view.
Other layers include: epigenome-layer, transcriptome-layer, proteome-layer
Each layer can compensate for deficiencies in another layer.
So lets say you knock out a gene in utero and it has a phenotype. But when you do the same procedure in an adult organism, there is no phenotype, although the gene should be important in an adult. It's like phenotype and genotype are two states whose correlation is dependent on many variables. In this example at least time.
Other layers include: epigenome-layer, transcriptome-layer, proteome-layer
Each layer can compensate for deficiencies in another layer.
So lets say you knock out a gene in utero and it has a phenotype. But when you do the same procedure in an adult organism, there is no phenotype, although the gene should be important in an adult. It's like phenotype and genotype are two states whose correlation is dependent on many variables. In this example at least time.
The first domino between the present and a world full of cat girls has fallen.
At what age would it be too late to try this? Asking for a friend...
It needs to be done at the embryonic stage before cell division so that as the cells replicate, they inherit the desired changes. The technology isn't quite there yet to transfect every single cell in an adult body with a virus containing the desired genetic modifications. Also, I can only imagine the downstream of effects of the body transcribing this modified dna in a fully-developed human. Have you ever seen the movie The Fly?
Loved the fly!
The holy grail of gene editing will be when we can make “permanent” changes to the DNA of people alive today.
I’d really enjoy a prehensile tail, despite the adaptations required for trousers and chairs.
Also, I was enough a nerd growing up that other kids would have pulled it.
Also, I was enough a nerd growing up that other kids would have pulled it.
i suspect there would be adaptations to a variety of other things like sleep, bipedal locomotion, defecation, etc.
I suspect our tailed ancestors slept, locomoted, and defecated.
Could just ask this guy how well things work for him:
https://www.guinnessworldrecords.com/world-records/114937-lo...
https://www.guinnessworldrecords.com/world-records/114937-lo...
I think we'd definitely have to rethink our toilets, though. Don't want your tail hanging in there while you're doing your business.
In much of the world (weighted by humans) people use squat toilets. So, problem is solvable by installing one after your CRISPR tail procedure.
What kind of tail are we looking at? One like a bunny or something like a cat?
I'm hoping for more like a dynosaur tail.
I am pretty sure there would be new dimensions to sexual behavior, details depending on the motor control we'd have.
> i suspect there would be adaptations to a variety of other things like sleep, bipedal locomotion, defecation, etc.
Sleep is easy: sleep on your side.
The rest sound like non-issues to me.
Sleep is easy: sleep on your side.
The rest sound like non-issues to me.
Probably good that we lost them. Judging by photos [1] of some of the rare cases of humans who were born with tails human tails wouldn't be aesthetically pleasing. Although perhaps human tails that are the result of something going awry might not be a good indicator of what human tails would be like if we had kept them.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263034/
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263034/
If we kept tails both the tails and our sense of what is attractive would be under evolutionary pressures so they probably would be normal to us!
Exactly. I still find noses and ears to be such noticeable protrusions once I let go of my knowledge of human faces.
If we'd never lost tails, probably we wouldn't find then so "un-human". Also, presumably most people would have "normal" (as in, the same as most others) tails, rather than like the images in that article.
NSFW, in case you are thinking about checking the link out.
This comment needs to be higher.
Clearly you haven't heard of catgirls.
Although those photos were more dickbutt than catgirl.
Would be cool if we had tails, so I could wag it with my future dog!
But imagine if your tail was hairless :/
That sounds like an opportunity for a whole industry to emerge tbh.
Hi we are Tailstyle! For far too long we’ve been accepting that our tails need to be naked like the rest of our bodies. Today I am offering you a share in our company for a very good price. Sharks, listen, everyone knows that wigs and toupees are amazing. What if I told you that my company we can put semi-permanent hair on your tail to look like a tiger! Or a panther? Or you could even have your tail look like that big flying dog in that one movie from the 80s you know which one I mean.
And not only that. We’re also making tail socks that you can wear for special occasions! Christmas tail socks. Wedding tail socks. Funeral tail socks. Homecoming ball tail socks. You name it!
Hi we are Tailstyle! For far too long we’ve been accepting that our tails need to be naked like the rest of our bodies. Today I am offering you a share in our company for a very good price. Sharks, listen, everyone knows that wigs and toupees are amazing. What if I told you that my company we can put semi-permanent hair on your tail to look like a tiger! Or a panther? Or you could even have your tail look like that big flying dog in that one movie from the 80s you know which one I mean.
And not only that. We’re also making tail socks that you can wear for special occasions! Christmas tail socks. Wedding tail socks. Funeral tail socks. Homecoming ball tail socks. You name it!
There are already companies that make tails. Not much of a jump to styling existing tails.
Tailscale.
Yeah but those guys would probably pivot to making lizard tails for the people. That’s respectable too. I just think the demand for fur-covered tails is a bigger potential market.
I imagine that it could still look cool if it were shaped/tapered in just the right way, maybe somewhere between that of a Sphynx cat and a lizard.
Imagine if it was covered in pubes. That would definitely be worse.
I'm not sure that would be as much of a problem as one might think, considering that many if not a majority of males today do just fine with their faces covered in pubes.
And also the people with a head-full of "pubes". People and cultures adapt.
Link to the open access article : https://www.nature.com/articles/s41586-024-07095-8
If you scroll to the bottom check out how long this article went into peer review: almost 3 years!
Three years can get you a PhD in UK.
Received 14 September 2021
Accepted 19 January 2024
Published 28 February 2024
If you scroll to the bottom check out how long this article went into peer review: almost 3 years!
Three years can get you a PhD in UK.
Received 14 September 2021
Accepted 19 January 2024
Published 28 February 2024
Is that normal? I imagine the poor bastards wanted to put it on their CV for their next job.
https://www.nature.com/nature-portfolio/about/journal-metric...
Median time is 268 days to acceptance at Nature. So this article was closer to 1000 days, above average.
Median time is 268 days to acceptance at Nature. So this article was closer to 1000 days, above average.
time to bring it back then, alongside horn implants, and third tit.
How about a third eye?
"The parietal eye is found in the tuatara, most lizards, frogs, salamanders, certain bony fish, sharks, and lampreys...It is absent in mammals, but was present in their closest extinct relatives, the therapsids"
https://en.wikipedia.org/wiki/Parietal_eye
You may wish to consult your pineal gland.
"The parietal eye is found in the tuatara, most lizards, frogs, salamanders, certain bony fish, sharks, and lampreys...It is absent in mammals, but was present in their closest extinct relatives, the therapsids"
https://en.wikipedia.org/wiki/Parietal_eye
You may wish to consult your pineal gland.
wings
Wings are so fascinating. Flying animals have their whole body, from their brain, digestive system, down to their bones internal structure and function [0] optimized for flight. That's where we see species giving up flight ability to get a stronger body, and I wonder what it would take for us to do the reverse to be able to use these wings in any way.
[0] https://www.montananaturalist.org/blog-post/avian-adaptation...
[0] https://www.montananaturalist.org/blog-post/avian-adaptation...
We'd definitely have to give up long gestation and with that, live birth, and probably a good amount of cranial capacity due to weight and energy budget tradeoffs.
Huh? Bats have most of those those, more than most other mammals their size.
Bats do not have the cranial size of humans; that's kind of the point. They may have a loosely comparable cranium to body mass proportion, but allometric mass scaling matters with respect to physiological adaptation, quite a lot[0].
[0] https://www.phys.ufl.edu/courses/phy3221/spring10/HaldaneRig...
[0] https://www.phys.ufl.edu/courses/phy3221/spring10/HaldaneRig...
Just need to go to Titan
atmosphere thick enough, gravity low enough
atmosphere thick enough, gravity low enough
It would be an awful trade. Weaker, dumber, slower. All for something that isn’t very good and we wouldn’t use very much.
People would prefer to drive rather than fly because you’ll get soaking wet. Unless you just go around naked or something.
People would prefer to drive rather than fly because you’ll get soaking wet. Unless you just go around naked or something.
It's not all it's cracked up to be - https://craphound.com/someone/Cory_Doctorow_-_Someone_Comes_...
Would be handy for navigating the warp. ;)
Third nipples are quite common believe it or not. Most people with them believe they’re moles.
Yup, I've seen a few. There's even a line on each side of the body that they tend to emerge along, arcing from the armpit down to the crotch.
I'd I'd be drinking milk, it would be out of my nostrils right about now.
Why does the article mainly focus on the great apes? All apes, including gibbons lost their tails.
The actual article in Nature points out that there have been independent tail-loss events in non-hominoid monkeys. Which makes it all the more frustrating that gibbons aren't mentioned anywhere. Given when they identify the mutation as having occurred, we can tentatively conclude that gibbons lack a tail for the same reason other apes do: 25 million years for the mutation, and 16.8 million years for the divergence of gibbons from the great apes.
Presumably because humans are great apes.
They buried the lede:
Even if the driving mutation identified in the study could be undone, “it still wouldn’t bring back the tail.”
Oh well.
Even if the driving mutation identified in the study could be undone, “it still wouldn’t bring back the tail.”
Oh well.
So I’m guessing this is less like, “we found the flag that toggles tail production” and more “we found a chunk of code that belongs to tail production”?
The first bit of the article sure makes it sound like this DNA is what does it all.
The first bit of the article sure makes it sound like this DNA is what does it all.
The scientists believed that the extra AluY element was functionally working to block out a part the TBXT gene (exon6). In their mouse model, they first directly snipped out exon6, and found that mice that were heterogeneous wildtype TBXT and exon6 removed TBXT developed a full spectrum of tail phenotypes from no tail to full length tail. At this point, the statement is "These results provide further evidence that the presence of TBXTΔexon6 is sufficient to induce tail loss".
They then tried to "more realistically" replicate the scenario. Instead of just snipping out exon6, they tried inserting in various elements into the mouse TBXT gene to emulate their model of how AluY is cutting out exon6. They attempted a few different methods which resulted in different models that would end up with different relative amounts of TBXT missing exon6 being produced. I'm having a hard time tracking all their conditions and lines at this point, but they seem to claim here that higher amounts of exon6 drop out correspond to shorter tails.
They also found that they could not get any viable mice with exon6 snipped from both copies of TBXT.
TBXT itself is a transcription factor, meaning that it controls the expression of other genes. There's probably a set of genes elsewhere that together make up the "tail-making machinery" that TBXT heavily interacts with. In this sense, TBXT 'might' be the most important single point lever, but at the same time not be fully in control of the underlying machine.
What does seem persuasive is that idea that this mutation kicked off some rate of tail lose in our ancestors, which then lead to some sort of selection advantage. The advantage was then made more durable by accumulating additional mutations to lock in the phenotype. In addition, once the "tail making machinery" is inactive, we have no idea how those genes might have been repurposed. I think it's in this sense that the scientists say that we probably can't bring tails back just by "fixing TBXT".
They then tried to "more realistically" replicate the scenario. Instead of just snipping out exon6, they tried inserting in various elements into the mouse TBXT gene to emulate their model of how AluY is cutting out exon6. They attempted a few different methods which resulted in different models that would end up with different relative amounts of TBXT missing exon6 being produced. I'm having a hard time tracking all their conditions and lines at this point, but they seem to claim here that higher amounts of exon6 drop out correspond to shorter tails.
They also found that they could not get any viable mice with exon6 snipped from both copies of TBXT.
TBXT itself is a transcription factor, meaning that it controls the expression of other genes. There's probably a set of genes elsewhere that together make up the "tail-making machinery" that TBXT heavily interacts with. In this sense, TBXT 'might' be the most important single point lever, but at the same time not be fully in control of the underlying machine.
What does seem persuasive is that idea that this mutation kicked off some rate of tail lose in our ancestors, which then lead to some sort of selection advantage. The advantage was then made more durable by accumulating additional mutations to lock in the phenotype. In addition, once the "tail making machinery" is inactive, we have no idea how those genes might have been repurposed. I think it's in this sense that the scientists say that we probably can't bring tails back just by "fixing TBXT".
Just wanted to say thanks for this excellent summary!
We found the flag that toggled tail production, but the tail production code is no longer in the codebase so turning on the flag again wouldn't do anything anymore.
The code might still be there, but there are no tests for it, there have been millions of years of spaghetti code refactoring in between, and there aren't even any checksums on the storage to verify data integrity.
Probably the difference between necessary and sufficient.
There are some people who are born with tails, though:
https://www.webmd.com/baby/what-is-a-human-tail
https://www.webmd.com/baby/what-is-a-human-tail
They aren't trying hard enough,then.
So close!
The greatest thing on this thread is how disappointed we all are for some bizarre reason lol. It would be cool to get them back for better balance.
A prehensile tail would do so much for my cooking skills... the possibilities are infinite.
Wait - I finally found a use case for Neuralink that I can cheer for!
Wait - I finally found a use case for Neuralink that I can cheer for!
You don't necessarily even need invasive surgery to control an additional limb: https://spectrum.ieee.org/human-augmentation
Exactly! And why stop at only one extra appendage?
I have always lamented the loss of the tail. Every time my dog, though almost entirely asleep, wags its tail to acknowledge my presence, I always say to myself "Now, THAT is efficiency."
I'm not a furry, but I'm open to the possibility of getting that back!
I'm not a furry, but I'm open to the possibility of getting that back!
My favorite "Scan Scene" from The Congress (Ari Folman's film based on Stanislaw Lem's novel "The Futurological Congress"), in which Harvey Keitel's character "Al" tells Robin Wright's character "Robin" the twisted tail of "Joey Fairytail"...
https://www.youtube.com/watch?v=pPAl5GwvdY8
https://www.youtube.com/watch?v=pPAl5GwvdY8
I love the book!
"The Congress" is to "The Futurological Congress" is to Stanislaw Lem like "Blade Runner" is to "Do Androids Dream of Electric Sheep" is to Philip K Dick.
Both great movies loosely based on both great but very different books by great authors, each with something unique and deep and important to say, that all stand on their own and are worth knowing.
Both great movies loosely based on both great but very different books by great authors, each with something unique and deep and important to say, that all stand on their own and are worth knowing.
Wait until you've seen the Ijon Tichy miniseries. It's .. a different approach.
Makes me think of the episode of the Simpsons where Marge was modified to be some kind of human feline in the episode The Island of Dr. Hibbert
Those hackers might get what they wanted. Real life catgirls. It would be so awesome.
Humans never had tails, just ask charlie brown.
A tail is grabbable.
I'd think in primate fighting, a tail would be big negative. It could be grabbed.
Can you imagine Chimp fights if they had tails that could be held on to and the owner dragged around.
I'd think in primate fighting, a tail would be big negative. It could be grabbed.
Can you imagine Chimp fights if they had tails that could be held on to and the owner dragged around.
The NFL would definitely have to come up with a rule about grabbing the tail of an opposing player.
Hair is much worse in that regard, as the tail would be positioned too low to practically grab (it would asking for a knee to the face or punches to the back of the head or spine if you tried). I think the driver is more likely to be bipedality. A tail doesn't provide a lot of benefit for balance or rearside whisker utility when moving on two legs, and would interfere with sitting and lying postures. I think humans are probably too large for practical prehensile tails too.
>and would interfere with sitting and lying postures.
I think that assumes that a hypothetical modern human tail would still be attached to the spine. A tail structure attached to the main body only through soft tissues could be flexible enough at the root to not be an issue.
I think that assumes that a hypothetical modern human tail would still be attached to the spine. A tail structure attached to the main body only through soft tissues could be flexible enough at the root to not be an issue.
The tail is just the end of the spine. I think it would be extremly difficult to evolve one that is not connected.
I imagine it would involve taking the one that is connected and evolving one that isn't (slow selection for a smaller connecting vertebra until it becomes vestigial). Floating bones aren't uncommon (you have one in your neck); the real wrench is that it's usually for entirely vestigial limbs, not vestigial portions of functional limbs. But I'm sure life could uh find a way.
I think it would be hard because without breaking the spinal cord. Floating "side" bones are possible, but I don't know any case where the spine has been split. The spine is too central to early devdelopment to mess with it without causing chaos in later steps of development.
> I think the driver is more likely to be bipedality.
Given that the tail was lost before the development of bipedality, how could this possibly be the case?
Given that the tail was lost before the development of bipedality, how could this possibly be the case?
> I think humans are probably too large for practical prehensile tails too.
There’s only one way to find out! Who wants to join my ‘prehensile tails for humans’ (and other great apes with cash) startup?
Capitalism, wow!
There’s only one way to find out! Who wants to join my ‘prehensile tails for humans’ (and other great apes with cash) startup?
Capitalism, wow!
The problem might be size, lots of smaller primates have tails which can be very useful as a fifth arm for holding onto branches. As you get larger, tree foraging becomes less viable and the tail less useful and it would need to be oversized to be able to function properly.
This seems like one of the times I can mention that dolphins and elephants have evolved prehensile penises. Sometimes nature finds a way.
And tapirs
Most of animals don't use tails as a fifth arm. My cat seems to use it for extra balance. I think that humans could do that as well.
Most animals are less dexterous than primates anyway. Humans talk about needing (or name products) a third arm/hand; small monkeys and lemurs and the like swing from them or use like you might imagine we would as an extra limb in climbing.
Mine used to use it to tickle my nostrils and make me sneeze for its own amusement when standing or walking over my lap.
I don't follow. You can grab leg and drag owner around. How's tail different?
A leg has rigidity due to its endoskeleton, as well as strong muscles with good leverage, which when conditions are right gives it insane strength as it can act as a mechanical lever.
Since a tail does not have a rigid endoskeleton, it can not act well as a lever. It's functionally a rope attached to your butt. Like even if you go full kangaroo mode and make the tail more muscular than the legs, making the tail rigid by flexing really hard, it basically turns into an inefficient leg with enormous mechanical disadvantages.
Since a tail does not have a rigid endoskeleton, it can not act well as a lever. It's functionally a rope attached to your butt. Like even if you go full kangaroo mode and make the tail more muscular than the legs, making the tail rigid by flexing really hard, it basically turns into an inefficient leg with enormous mechanical disadvantages.
But the lack of ridigity also means that it's actually quite hard to control someone through it.
If you grab someone's leg, especially near the foot/ankle, you are relying on the rigidity of the joints to be able to control their torso (and therefore their ability to fight back). The most disadvantageous position to be in is to have someone behind you, while they fully control your ankle/foot. Now you can't fully turn your body to face your opponent.
For a sufficiently flexible tail, that would not be the case. Some could be behind you and control your tail near the tip, and you could still fully turn into your attacker with your torso.
This isn't to say that a tail can't become a liability.
If you grab someone's leg, especially near the foot/ankle, you are relying on the rigidity of the joints to be able to control their torso (and therefore their ability to fight back). The most disadvantageous position to be in is to have someone behind you, while they fully control your ankle/foot. Now you can't fully turn your body to face your opponent.
For a sufficiently flexible tail, that would not be the case. Some could be behind you and control your tail near the tip, and you could still fully turn into your attacker with your torso.
This isn't to say that a tail can't become a liability.
We have two legs, so grabbing one is a good way to get kicked in the face (or elsewhere).
A flexible tail doesn’t have that disadvantage to the grabber, especially if longer than a leg.
A flexible tail doesn’t have that disadvantage to the grabber, especially if longer than a leg.
You can’t land a kick when someone has your foot. Gravity exists, you will immediately fall onto your butt as soon as you lift the other leg.
On the ground is perfect for kicking them in the nuts, leg/torso strikes, sweeping their legs, or various control locks. It's a near ideal place to be to also get your opponent on the ground. You can also get a solid kick or sweep in, or throw them off balance on the way down too, if you're ready for it.
You might find BJJ pretty interesting. [https://renzogracieacademy.com/about/what-is-brazilian-jiu-j...], [https://www.youtube.com/watch?v=u0edxg2fFmw]
Judo teaches how to deal with it quite well too.
The legs are the strongest part of a human, the arms don't compare at all. And fighting from the ground can be VERY effective if you know what you're doing. Or don't just curl up and wait to die.
Ideally you'd be on your feet and able to move faster of course, and I wouldn't recommend against an opponent with a spear or other ranged weapon - but then they wouldn't be trying to grab my foot or leg anyway eh?
You might find BJJ pretty interesting. [https://renzogracieacademy.com/about/what-is-brazilian-jiu-j...], [https://www.youtube.com/watch?v=u0edxg2fFmw]
Judo teaches how to deal with it quite well too.
The legs are the strongest part of a human, the arms don't compare at all. And fighting from the ground can be VERY effective if you know what you're doing. Or don't just curl up and wait to die.
Ideally you'd be on your feet and able to move faster of course, and I wouldn't recommend against an opponent with a spear or other ranged weapon - but then they wouldn't be trying to grab my foot or leg anyway eh?
Although when striking is involved, leg locks loose much of their effectiveness.
It's always a race to get the critical hit or lock in.
But unless the 'grabee' doesn't do anything, someone grabbing one foot from someone is likely using both hands (and most of their upper body) to attempt to control it - and there is a second foot/leg out there free to cause a lot of damage if they're willing.
It's not a 'one and done'/'game over' scenario by any stretch of the imagination if the party is even a little motivated.
Though I suspect most folks in this thread have no exposure to an actual fight beyond watching a video somewhere, so....
But unless the 'grabee' doesn't do anything, someone grabbing one foot from someone is likely using both hands (and most of their upper body) to attempt to control it - and there is a second foot/leg out there free to cause a lot of damage if they're willing.
It's not a 'one and done'/'game over' scenario by any stretch of the imagination if the party is even a little motivated.
Though I suspect most folks in this thread have no exposure to an actual fight beyond watching a video somewhere, so....
Coming from a stand-up striking Muay Thai perspective the only low risk way to grab a leg is intercepting a kick. You are then out of range of their upper body attacks and have total leverage physically and tactically. At that point unless the fighter whose leg is grabbed is extremely experienced in keeping a one foot balance by avoiding sweeps (ignoring the fact that one can bring the fight to the ground in MMA or BJJ etc - which imo is not preferable in a street fight) they're in a supremely disadvantaged position and at the will of the grabber. In a tournament, though, these situations usually resolve very quickly one way way or the other.
With your background. Can you extrapolate on how a tail would impact you? Would it be a big negative to have something that can be grabbed.
Also. Chimps/Primates. Don't they fight more in packs.
So if the competition was 5 on 1, would the tail become an even greater disadvantage. It would be even harder to maneuver or run, become someone could grab the tail.
Also. Chimps/Primates. Don't they fight more in packs.
So if the competition was 5 on 1, would the tail become an even greater disadvantage. It would be even harder to maneuver or run, become someone could grab the tail.
I have two separate thoughts on the matter. One is whether a tail would provide me with additional balance and/or striking power. Potentially as a counterweight during round housed kicks or spinning back kicks. The second is that a tail by itself would be an inferior weapon to punches, elbows, knees, and kicks due to its relative fragility and potentially high nerve density.
So this leads to a utilitarian equation - is the additional counterbalance going to provide a sufficient edge to override the risk it adds of a relatively weak limb that can be grabbed?
So this leads to a utilitarian equation - is the additional counterbalance going to provide a sufficient edge to override the risk it adds of a relatively weak limb that can be grabbed?
As long as we're inventing limbs, why not put spikes at the end of the tail, like a stegosaurus' thagomizer. I bet that would be pretty fun to fight with.
Having done muay thai for several years - this is why muay thai doesn’t do well in less regulated environments, like MMA or actual street fights.
Because muay thai has a very structured set of rules and an environment which constrains it so that is the case. much less so than western boxing obviously, but the issue is even more obvious there.
generally still way better than no training of course.
BJJ folks consistently beat Muay Thai competitors in MMA for this reason.
being able to do both, plus some krav maga strikes? even better! though most krav maga if done with full earnestness would get you thrown in jail outside of a legit self defense scenario.
Because muay thai has a very structured set of rules and an environment which constrains it so that is the case. much less so than western boxing obviously, but the issue is even more obvious there.
generally still way better than no training of course.
BJJ folks consistently beat Muay Thai competitors in MMA for this reason.
being able to do both, plus some krav maga strikes? even better! though most krav maga if done with full earnestness would get you thrown in jail outside of a legit self defense scenario.
I agree with the octagon scenario, but not with a streetfight. If you're outnumbered, it is not advisable to go to ground. That is when rapid high damage strikes and the ability to dodge, block, or soak hits make you not just a physical weapon but psychological.
By the way, in full traditional muay thai, both quick and prolonged stand-up grappling is trained for.
By the way, in full traditional muay thai, both quick and prolonged stand-up grappling is trained for.
For me the main example of leg locks failing in MMA is Ilia Toporia's knockout of Ryan Hall in the UFC.
Also, many powerful leg locks entries fail to succeed in MMA, due to overcommitment of limbs.
Also, many powerful leg locks entries fail to succeed in MMA, due to overcommitment of limbs.
There are also a large number of banned moves in MMA. Nothing is perfect. Grabbing someones foot/leg isn't a one and done deal, either way, because we do actually have two and they're pretty powerful.
Right, but if we're seriously talking about the liabilities that having a tail has in a fight, then presumably most of the scenarios would involve attacking from behind. Remember also that this would be mostly quadraped animals too. Legs would have been strong, but likely still arboreally adapted, so a relatively strong upper body as well.
In such a scenario, you'd probably attack from behind from a bit of an angle to force strikes from the other leg to be severely cross body.
My original point was not that attacking the leg was easy, my point is that a flexible tail doesn't give you much leverage and control and may not be as much of a liability as you think, since if you could access the tail anyways, you probably also had their back.
In such a scenario, you'd probably attack from behind from a bit of an angle to force strikes from the other leg to be severely cross body.
My original point was not that attacking the leg was easy, my point is that a flexible tail doesn't give you much leverage and control and may not be as much of a liability as you think, since if you could access the tail anyways, you probably also had their back.
Legs have a lot more muscle to allow the owner to resist, along with the downward weight of the body somewhat adding to stability?
Replace tail by arm in your comment and see what is wrong about it.
Arms are powerful but tails are not.
Seriously? Cost benefit. Arms have more benefit but not this cost.
Monkeys have tails to swing and walk in trees.
Yet there's plenty of animals that have tails and don't spend time in trees, such as dogs, horses and cows.
The tail seems like vestigial anatomy (originally useful in fish) that has three possible states in mammals: 1. Repurposed for a new function (tree swinging, signals) 2. Not much used but still in the repo (mice) 3. Garbage collected (apes).
I'm curious about the "garbage collected" theory as there doesn't seem like a lot of selection pressure to remove tails simply due to them not being useful and consuming energy to grow. The appendix is a far more likely candidate for garbage collection as it has no obvious function and can easily cause death if it bursts.
I suspect that there's another reason that apes lost their tails - most likely related to walking on two feet.
Edit: According to this study (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/), the tailed chap had difficulty/pain when sitting and during other activites
I suspect that there's another reason that apes lost their tails - most likely related to walking on two feet.
Edit: According to this study (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/), the tailed chap had difficulty/pain when sitting and during other activites
In that study the tail was not innervated so there would be no way to voluntarily move the tail out of the way when sitting.
> The appendix is a far more likely candidate for garbage collection as it has no obvious function
Preserving the gut microbiome through diarrhoea and vomiting.
Preserving the gut microbiome through diarrhoea and vomiting.
I didn't know about that, but it seems a poor trade-off to me. Acute appendicitis is the most common abdominal surgical emergency in the world.
Yet most people never suffer it, while I'd assume 100% of the population suffered bouts of vomiting/diarrhea. Looks like the trade-off is alright.
Yeah, I suspect a lot more people have experienced diarrhea than appendicitis. If preserving gut bacteria is important enough, then the appendix clearly does have a function.
But it might not be that important at all; do people with an appendectomy struggle more to recover from diarrhea?
But it might not be that important at all; do people with an appendectomy struggle more to recover from diarrhea?
Tails are extremely useful to mice, especially for balance and climbing: https://www.theguardian.com/lifeandstyle/2019/apr/30/why--mi...
Be careful with assuming functionlessness, in general. Evolution does not like spending energy on sticky-out bits that are prone to injury, or good handles for predators to catch, unless they provide some serious advantage.
Be careful with assuming functionlessness, in general. Evolution does not like spending energy on sticky-out bits that are prone to injury, or good handles for predators to catch, unless they provide some serious advantage.
#1 covers a whole range of different possible functions, of course.
Balance and navigation (birds, cats, etc) is still somewhat related to the original function in fish.
Sexual attraction/signalling
Grabbing stuff
A third leg in kangaroos
Fly swatter (cows and other large grazers)
For kids to hold onto their parent (elephants)
I'm sure there's a lot of other creative applications of tails that I'm missing.
Balance and navigation (birds, cats, etc) is still somewhat related to the original function in fish.
Sexual attraction/signalling
Grabbing stuff
A third leg in kangaroos
Fly swatter (cows and other large grazers)
For kids to hold onto their parent (elephants)
I'm sure there's a lot of other creative applications of tails that I'm missing.
Kangaroos use their tails as a fifth leg - https://phys.org/news/2014-07-tale-kangaroo-tail.html
Also used to distract and confuse (deer and rabbits)
Yet, according to TFA, apes had already lost their tail while they were still tree dwellers.
Presumably as primates got bigger, tails were less useful (not strong enough to be prehensile appendages, and not as handy for balance if you climb methodically instead of carefree leaping).
Can't wait for the first Furry Liberation movement to take hold and campaign for their future kids to grow tails.
The decision to modify an embryo to have cat ears and a tail is a decision between doctor and parent!
As long as you get a doctor involved, no modification is too horrific.
As long as you get a doctor involved, no modification is too horrific.
Getting closer and closer to getting catgirls
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If we're doing germline edits, the obvious thing to fix first is vitamin synthesis. There are a bunch of useful things other living things synthesise from first principles, and we don't so we need to eat something that has already synthesised the thing we wanted, and we can't cook or preserve it in any way that destroys the material we needed or it won't work. That's what scurvy is, a tree or a lizard just makes its own vitamin C, but humans don't, so, if you're stuck on a ship eating preserved food for months your body runs out of vitamin C and you get very sick and eventually die. But synthesising vitamin C isn't hard per se, it's just that the synthesis instructions can be deleted and the humans are descended from an ancestor who had such a deletion, we can put it back.
Once vitamin synthesis is back working, next up is amino acid synthesis. Amino acids are the constituent parts of proteins, your DNA is a bunch of instructions to fasten together a series of 22 different coded amino acids to make proteins. When you eat something, any proteins are broken back down into amino acids. Given some amino acids you can in principle make the others, but humans only make about half of them this way. As a result if your protein mix is wrong you are eating amino acids, and your body needs amino acids but some of them are different amino acids - and instead of synthesising the ones needed from spares you don't need using energy, which is abundant in most human societies, you just get sick and eventually (if you don't fix your diet) die. We should fix that.
Once vitamin synthesis is back working, next up is amino acid synthesis. Amino acids are the constituent parts of proteins, your DNA is a bunch of instructions to fasten together a series of 22 different coded amino acids to make proteins. When you eat something, any proteins are broken back down into amino acids. Given some amino acids you can in principle make the others, but humans only make about half of them this way. As a result if your protein mix is wrong you are eating amino acids, and your body needs amino acids but some of them are different amino acids - and instead of synthesising the ones needed from spares you don't need using energy, which is abundant in most human societies, you just get sick and eventually (if you don't fix your diet) die. We should fix that.
I'm surprised how the conversation shifted from genetics to unethical germline editing of things that barely have clinical relevance. The rates of scurvy in the 21th century are low and definitely don't warrant super invasive editing germline cells (!), changes which become hereditary. Adding vitamin synethesis is super complex: it's not just a single SNP change but would require a whole new enzyme system. It's a very fine line from opening up a big old can of eugenics worms. Adding extra tRNAs is sometimes done in microbiology but any health benefits are extremely questionable. I've never before seen germline editing be a proposed 'solution' to malnutrition.
Vitamin synthesis is one of the most pointless things to add because it is something that is lost in many lineages over evolutionary time. The reason is that as long as there are environmental sources of a molecule the pressure to retain the ability to synthesize that molecule natively is zero or even negative, because the synthesis pathways for some of those molecules are quite nasty. You could do it, but those people would probably have increased cancer rates due to running nasty biochemistry in their own cells and eventually their descendants would lose the ability the synthesize it again because vitamin C is naturally present in their environment unless they are e.g. British sailors stuck on a boat for months with a evolutionary strange diet.
The main issue is that evolutionary pressures have optimized for and against certain things that have fragile interplay of consequences with other genes.
While it will become possible to restore auto-synthesis functionality, there are unknown risks associated with germ line edits reengineering Vit C or essential AA synthesis.
It's currently illegal to do so in 70 countries. Specific, very positive beneficial edits that protect against infections, malnutrition, or pathological diseases should be allowed.
While it will become possible to restore auto-synthesis functionality, there are unknown risks associated with germ line edits reengineering Vit C or essential AA synthesis.
It's currently illegal to do so in 70 countries. Specific, very positive beneficial edits that protect against infections, malnutrition, or pathological diseases should be allowed.
and then, crispr cat ears
Not the bombardier beetle's hydrogen peroxide cannon? I'll never understand furries.
(earflattens very slightly in Cat, otherwise impassive)
Don't judge.
Don't judge.
I mean, do you want Zootopia, or do you want that weird (strangely enjoyable) Jamie Foxx Netflix movie? Because one might be mundane, but at least you don't have to worry about some guy blowing you across the block with his shrimp powers.
Like that might be a bit problematic due to the existing ears but whatever - like, if designed well you might as well have an extra pair of fluffy cat/dog/fox ears and use it for improved echolocation. ;-)
Makes you wonder why we naturally selected for ancestors who didn't have the vitamin synthesis machinery. Clearly there must have been some evolutionary disadvantage associated with vitamin synthesis, or else as you say it's clear benefits should have conferred an evolutionary advantage and still be with us today.
Not necessarily. If any early human diet that produced enough calories for them to live and procreate also happened to have plenty of vitamins, then synthesizing your own really didn't confer any evolutionary advantage.
I'd also note I don't see any reason we'd want to synthesize our own vitamins now. It's virtually impossible to get a vitamin deficiency unless you try to eat a very restrictive diet for some other reason.
I'd also note I don't see any reason we'd want to synthesize our own vitamins now. It's virtually impossible to get a vitamin deficiency unless you try to eat a very restrictive diet for some other reason.
There was little selection selecting against the loss it when it was abundant in out ancestors diet at that particular time and place. so by the time it became an issue it was already missing from the gene pool and as it is easier for a mutaion to break a gene than it is to gain function so its unlikely to mutate back into the genome by chance.
If we are on this topic then we need to discuss a genetically modified gut microbiota. We do not need to edit genetically ourselves for some pityful vitamins. Microbiota could give us all we want. It could enable us to digest plastic, so we could eat food without removing its packaging. We could reduce severity of our waste problems by digesting plastic into relatively harmless poop.
Sounds unappetizing. Would you want to eat packaging if not for the - for now inevitable - digestion issues?
Yeah, you are right, it is not cool. How about to eat your fork? Can microbiota digest iron?
Maybe fix uricase production as well (eliminating gout).
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now all we need is for the tailbone/coccyx to disappear.
How long until humans have an actual "shelve" (indentation) on their pinkie at birth to rest their phone on?
Never.
Actually, considering how low the birth rates in developed countries are, humans would probably (very slowly) become less and less suitable for modern life.
Actually, considering how low the birth rates in developed countries are, humans would probably (very slowly) become less and less suitable for modern life.
I would hope that phones would not remain the last point in the evolution of a personal computing device in so far as to make it able to steer the evolution of humans.
Never.
Individuals with that kind of mutation have to be born per random chance, and then selected via sexual preference.
a long time? You probably need at least 7-9 generations to select "strong pinky shelf" as desirable and I'm not sure any culture is yet?
>You probably need at least 7-9 generations to select "strong pinky shelf" as desirable
It not only has to be convenient, but also to be sexually selected (partners with that seen as more attractive) or helping with survivability (partners with that live longer and get to reproduce more), which ain't really applicable anyway.
Which is the reason we don't have traits for any other minor "convenience" attribute either, but instead for long standing evolutionary benefits.
It not only has to be convenient, but also to be sexually selected (partners with that seen as more attractive) or helping with survivability (partners with that live longer and get to reproduce more), which ain't really applicable anyway.
Which is the reason we don't have traits for any other minor "convenience" attribute either, but instead for long standing evolutionary benefits.
It’s fascinating that most people don’t get that about evolution. It needs to be a matter of life and death, if it doesn’t, then it has no impact.
Surely it's more to do with the chances of raising viable offspring. A change that makes a person more desirable to the opposite sex is very likely to be selected for even if it makes the person more likely to die in their 50s.
‘It’s complicated’.
Blue eyes, for example.
Blue eyes, for example.
Don't blue eyes support the "sexual selection" over "life or death" view of evolution though? Blue eyes don't provide any benefits to the owner other than possible sexual selection and surprisingly, they evolved before fair skin (which does provide a benefit for people in northern latitudes to produce enough vitamin D).
>Don't blue eyes support the "sexual selection" over "life or death" view of evolution though?
Is it a choice? Evolution has both "life and death" and "sexual selection" aspects.
And "sexual selection" itself is tied to "life and death" - it just concerns the life and death (or rather: existence or non-existence) of the offspring and not the person.
So, in any case, it has to be big enough to affect whether the person gets an advantage in living more themselves, or gets an advantage for having children come to life.
Is it a choice? Evolution has both "life and death" and "sexual selection" aspects.
And "sexual selection" itself is tied to "life and death" - it just concerns the life and death (or rather: existence or non-existence) of the offspring and not the person.
So, in any case, it has to be big enough to affect whether the person gets an advantage in living more themselves, or gets an advantage for having children come to life.
Well yes, it's both.
I was replying to jeromegv's earlier comment of:
> It’s fascinating that most people don’t get that about evolution. It needs to be a matter of life and death, if it doesn’t, then it has no impact.
I was replying to jeromegv's earlier comment of:
> It’s fascinating that most people don’t get that about evolution. It needs to be a matter of life and death, if it doesn’t, then it has no impact.
I'd even generalize it to 'it's about passing on ones genes'.
Death before one has had a chance to do so (or before any necessary utility towards one's offspring has passed) is evolutionarily 'bad'.
Things that help reproduction and success for one's offspring? Evolutionarily 'good'.
The tricky part is that a large portion of ANY human population is, near as I can tell, 'excess'/'hedging' population, and so will be 'doing poorly' in any given set of circumstances. Think of it as 'build time attribute randomization' when there is a random situation picked that people couldn't predict in advance.
That means that population wide, when circumstances change, the portion that is doing poorly vs doing very well can shift appropriately so the overall population survives. It is quite expensive, but seems necessary for us to have survived so long overall with the sheer number of apocalypses we know of (from plagues to invading armies), and the undoubtably countless ones we have forgotten.
This is true of any group or subgroup.
Death before one has had a chance to do so (or before any necessary utility towards one's offspring has passed) is evolutionarily 'bad'.
Things that help reproduction and success for one's offspring? Evolutionarily 'good'.
The tricky part is that a large portion of ANY human population is, near as I can tell, 'excess'/'hedging' population, and so will be 'doing poorly' in any given set of circumstances. Think of it as 'build time attribute randomization' when there is a random situation picked that people couldn't predict in advance.
That means that population wide, when circumstances change, the portion that is doing poorly vs doing very well can shift appropriately so the overall population survives. It is quite expensive, but seems necessary for us to have survived so long overall with the sheer number of apocalypses we know of (from plagues to invading armies), and the undoubtably countless ones we have forgotten.
This is true of any group or subgroup.
blue eyes have better night vision. video related
https://www.youtube.com/watch?v=FgAIWpVSAM8
https://www.youtube.com/watch?v=FgAIWpVSAM8
Thanks, I did not know that.
Lower chance of cataracts too.
Lower chance of cataracts too.
Even in case something helps with survivability, the benefit must be strong enough to be selected for. Even today people are dying because of appendicitis, can't imagine the death rate in the pre-modern era.
Given evolution? Thousands of years...
It takes metabolic resources to grow a tail. If the benefit was less than the cost, mutations that prevented the tail from growing were selected for.
And they're unhygenic. Sheep farmers for instance routinely cut the tails of their flock because it is difficult to shear and becomes a breeding ground for blowfly larvae. That said, i saw a movie called Shallow Hal(2001) which had a scene in which a man was shown to have a tail. Now it may have been cgi, but it made me think that there must be a minority of humans with that mutation.
but it made me think that there must be a minority of humans with that mutation
There certainly are, but it is extremely rare: https://en.wikipedia.org/wiki/Tail#Human_tails
There certainly are, but it is extremely rare: https://en.wikipedia.org/wiki/Tail#Human_tails
Its not because of the tail but because of the farms. Sad state of how we do farming at scale.
If someone can think of a better way to feed 8 billion people into obesity and early death cheaply then we'll do that instead.
whythre(6)
There is no "why" -- it happened and was not selected against; it may have been adaptive and that is a kind of why, I guess. I think it would be better to be clear about this in science communication.
The article itself states that this may be the case, or that it might have had some evolutionary advantage that we're just not aware of.
> There is no "why"
Of course there is a why. It happend and not only was it not selected against, presence of a tail was selected against. Meaning it was, or came along with a beneficial adaptation. That benefit is why it took over our gene pool and why we don't have tails now.
Of course there is a why. It happend and not only was it not selected against, presence of a tail was selected against. Meaning it was, or came along with a beneficial adaptation. That benefit is why it took over our gene pool and why we don't have tails now.
There has to be more to it.
If it’s not selected against, it wouldn’t spread at the cost of the tail gene.
Somehow, somewhere along the genome line, non-tailers overtook tailers.
If it’s not selected against, it wouldn’t spread at the cost of the tail gene.
Somehow, somewhere along the genome line, non-tailers overtook tailers.
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@dang Editorialized title; original title for the CNN article is "Why don’t humans have tails? Scientists find answers in an unlikely place"
So they hired radicals to genetically engineer a retrovirus, to remove the tail. This worked, but due to unconsidered balance issues, all tail devoid children lost the capability for bipedal balance and therefore walking.
Most of these children, during their formative years spent their time on all fours, and thud their hand dexterity was pitiful, and society crumbled when they came of age.
It was another 46k years before a brain mutation emerged, re-enabling bipedal balance, but by that time all traces of the old civilization was lost, and thus, progress began anew.