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Scientists have traced human tail loss to a short sequence of genetic code

cnn.com

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Re: Scientists have traced human tail loss to a short sequence of genetic code

#211

Post by mcv »

dboreham wrote: post #67
ndsipa_pomu wrote: post #50

Earlier quoted context omitted.

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).

#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.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#212

Post by PunchTornado »

j7ake wrote: post #155

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

Is that normal? I imagine the poor bastards wanted to put it on their CV for their next job.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#213

Post by withinboredom »

tzs wrote: post #60

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/

NSFW, in case you are thinking about checking the link out.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#214

Post by ItCouldBeWorse »

npstr wrote: post #170
KennyBlanken wrote: post #164

Earlier quoted context omitted.

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...

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...

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.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#215

Post by gus_massa »

underlipton wrote: post #160
gus_massa wrote: post #154

Earlier quoted context omitted.

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.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#216

Post by FrustratedMonky »

datameta wrote: post #99
lazide wrote: post #90

Earlier quoted context omitted.

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 l…

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 B…

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.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#217

Post by dtech »

temporalparts wrote: post #181
npstr wrote: post #170

Earlier quoted context omitted.

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...

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?

There are many crabs because of convergent evolution, in this analogy that has nothing to do with refactoring. That is more similar to competing products having a lot of the same features.

Re: Scientists have traced human tail loss to a short sequence of genetic code

#218

Post by m4rtink »

ruined wrote: post #80
tialaramex wrote: post #69

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…

and then, crispr cat ears

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. ;-)

Re: Scientists have traced human tail loss to a short sequence of genetic code

#219

Post by swader999 »

joshuamcginnis wrote: post #139

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.

At what age would it be too late to try this? Asking for a friend...
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