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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

#81

Post by klyrs »

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

Not the bombardier beetle's hydrogen peroxide cannon? I'll never understand furries.

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

#83

Post by lazide »

ndsipa_pomu wrote: post #58
coldtea wrote: post #57

Earlier quoted context omitted.

> 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 pers…

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'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.

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

#84

Post by LorenzoGood »

lazide wrote: post #79
kjkjadksj wrote: post #74

Earlier quoted context omitted.

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... ], [ http…

Although when striking is involved, leg locks loose much of their effectiveness.

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

#85

Post by thaumasiotes »

t-3 wrote: post #27
FrustratedMonky wrote: post #5

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.

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 a…

> 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?

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

#87

Post by canadiantim »

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…

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.

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

#88

Post by BoiledCabbage »

ngvrnd wrote: post #42

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.

> 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.

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

#89

Post by samatman »

ginko wrote: post #32

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.

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

#90

Post by lazide »

LorenzoGood wrote: post #84
lazide wrote: post #79

Earlier quoted context omitted.

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... ], [ http…

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....

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