It turns out that the common ancestor that between gibbons and the great
apes had an ALU transposon jump into the intron between exon 6 and exon
7 of the TBXT gene. There was already an transposon between exon 5 and
exon 6. Monkeys and apes have the ALU insertion in the intron between
exon 5 and exon 6, but the apes have the second ALU insertion in the
intron between exons 6 and 7. So it turns out that apes still have the
exon 6 sequence in the TBXT gene, but the two ALU transposon sequences
form a stem loop structure in the RNA transcript that messes up
processing so exon 6 is skipped and exon 5 is stuck to exon 7 in the
final ape mRNA. So part of what makes us human is due to a transposon
insertion mutation into the TBXT gene.

The insertion happened in the common ancestor of all extant apes, and
has been retained by the extant ape lineages.

https://www.nature.com/articles/s41586-024-07095-8

The article is open access.

Ron Okimoto

On 2/28/24 3:21 PM, RonO wrote:
> It turns out that the common ancestor that between gibbons and the great
> apes had an ALU transposon jump into the intron between exon 6 and exon
> 7 of the TBXT gene.  There was already an transposon between exon 5 and
> exon 6.  Monkeys and apes have the ALU insertion in the intron between
> exon 5 and exon 6, but the apes have the second ALU insertion in the
> intron between exons 6 and 7.  So it turns out that apes still have the
> exon 6 sequence in the TBXT gene, but the two ALU transposon sequences
> form a stem loop structure in the RNA transcript that messes up
> processing so exon 6 is skipped and exon 5 is stuck to exon 7 in the
> final ape mRNA.  So part of what makes us human is due to a transposon
> insertion mutation into the TBXT gene.
>
> The insertion happened in the common ancestor of all extant apes, and
> has been retained by the extant ape lineages.
>
> https://www.nature.com/articles/s41586-024-07095-8
>
> The article is open access.
>
> Ron Okimoto
>
Another effect of this modification is also "Moreover, mice expressing
the exon-skipped Tbxt isoform develop neural tube defects, a condition
that affects approximately 1 in 1,000 neonates in humans10. Thus,
tail-loss evolution may have been associated with an adaptive cost of
the potential for neural tube defects, which continue to affect human
health today."

Evidently, the advantages of losing the tail outweigh the disadvantage
of the neural tube defects.

On 2/28/2024 5:41 PM, erik simpson wrote:
> On 2/28/24 3:21 PM, RonO wrote:
>> It turns out that the common ancestor that between gibbons and the
>> great apes had an ALU transposon jump into the intron between exon 6
>> and exon 7 of the TBXT gene.  There was already an transposon between
>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>> intron between exon 5 and exon 6, but the apes have the second ALU
>> insertion in the intron between exons 6 and 7.  So it turns out that
>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>> transposon sequences form a stem loop structure in the RNA transcript
>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>> to a transposon insertion mutation into the TBXT gene.
>>
>> The insertion happened in the common ancestor of all extant apes, and
>> has been retained by the extant ape lineages.
>>
>> https://www.nature.com/articles/s41586-024-07095-8
>>
>> The article is open access.
>>
>> Ron Okimoto
>>
> Another effect of this modification is also "Moreover, mice expressing
> the exon-skipped Tbxt isoform develop neural tube defects, a condition
> that affects approximately 1 in 1,000 neonates in humans10. Thus,
> tail-loss evolution may have been associated with an adaptive cost of
> the potential for neural tube defects, which continue to affect human
> health today."
>
> Evidently, the advantages of losing the tail outweigh the disadvantage
> of the neural tube defects.
>

What were the advantages?

Some other simian lineages have lost their tails, but what is the advantage?

Apes did become brachiators, but other simian lineages did not, and some
simian lineages that adopted a similar lifestyle for supporting
themselves in the trees, actually developed prehensile tails as a fifth
limb for supporting themselves hanging from branches.

For birds there was a selective advantage in terms of weight, and the
tailbones degenerated and fused into a small nub. The tail was not
lost, and birds still have a nub that they call a pygostyle that still
supports the muscles that control the tail movements and so the feathers
associated with the tail.

Ron Okimoto

It happens that RonO formulated :
> On 2/28/2024 5:41 PM, erik simpson wrote:
>> On 2/28/24 3:21 PM, RonO wrote:
>>> It turns out that the common ancestor that between gibbons and the great
>>> apes had an ALU transposon jump into the intron between exon 6 and exon 7
>>> of the TBXT gene.  There was already an transposon between exon 5 and exon
>>> 6.  Monkeys and apes have the ALU insertion in the intron between exon 5
>>> and exon 6, but the apes have the second ALU insertion in the intron
>>> between exons 6 and 7.  So it turns out that apes still have the exon 6
>>> sequence in the TBXT gene, but the two ALU transposon sequences form a
>>> stem loop structure in the RNA transcript that messes up processing so
>>> exon 6 is skipped and exon 5 is stuck to exon 7 in the final ape mRNA.  So
>>> part of what makes us human is due to a transposon insertion mutation into
>>> the TBXT gene.
>>>
>>> The insertion happened in the common ancestor of all extant apes, and has
>>> been retained by the extant ape lineages.
>>>
>>> https://www.nature.com/articles/s41586-024-07095-8
>>>
>>> The article is open access.
>>>
>>> Ron Okimoto
>>>
>> Another effect of this modification is also "Moreover, mice expressing the
>> exon-skipped Tbxt isoform develop neural tube defects, a condition that
>> affects approximately 1 in 1,000 neonates in humans10. Thus, tail-loss
>> evolution may have been associated with an adaptive cost of the potential
>> for neural tube defects, which continue to affect human health today."
>>
>> Evidently, the advantages of losing the tail outweigh the disadvantage of
>> the neural tube defects.
>>
>
> What were the advantages?
>
> Some other simian lineages have lost their tails, but what is the advantage?
>
> Apes did become brachiators, but other simian lineages did not, and some
> simian lineages that adopted a similar lifestyle for supporting themselves in
> the trees, actually developed prehensile tails as a fifth limb for supporting
> themselves hanging from branches.
>
> For birds there was a selective advantage in terms of weight, and the
> tailbones degenerated and fused into a small nub. The tail was not lost, and
> birds still have a nub that they call a pygostyle that still supports the
> muscles that control the tail movements and so the feathers associated with
> the tail.
>
> Ron Okimoto

I suppose sitting is much easier without a tail.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/

On 28/02/2024 23:41, erik simpson wrote:
> On 2/28/24 3:21 PM, RonO wrote:
>> It turns out that the common ancestor that between gibbons and the
>> great apes had an ALU transposon jump into the intron between exon 6
>> and exon 7 of the TBXT gene.  There was already an transposon between
>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>> intron between exon 5 and exon 6, but the apes have the second ALU
>> insertion in the intron between exons 6 and 7.  So it turns out that
>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>> transposon sequences form a stem loop structure in the RNA transcript
>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>> to a transposon insertion mutation into the TBXT gene.
>>
>> The insertion happened in the common ancestor of all extant apes, and
>> has been retained by the extant ape lineages.
>>
>> https://www.nature.com/articles/s41586-024-07095-8
>>
>> The article is open access.
>>
>> Ron Okimoto
>>
> Another effect of this modification is also "Moreover, mice expressing
> the exon-skipped Tbxt isoform develop neural tube defects, a condition
> that affects approximately 1 in 1,000 neonates in humans10. Thus,
> tail-loss evolution may have been associated with an adaptive cost of
> the potential for neural tube defects, which continue to affect human
> health today."

The association of neural tube defects with the loss of the tail is a
leap. That exon deletion on a murine genetic background results in
neural tube defects doesn't necessarily mean that it does so on a simian
genetic background. One could inquire of the baseline rate of neural
tube defects in cercopithecids and murids.

Another leap is dating the loss of the tail to the
cercopithecoid/hominoid split, rather than later. Referring to wiki I
find that propliopithecids are now considered basal catarrhines rather
than basal apes, so there's no example of a tailed ape that I can point
to. (I am now led to ask what evidence do we have that apes outside the
hominoid crown group were tailless - naively one would have to have a
fused os coccyx preserved to answer the question.)
>
> Evidently, the advantages of losing the tail outweigh the disadvantage
> of the neural tube defects.
>

The existence of nearly-neutral evolution has to be remembered.

--
alias Ernest Major

On 2/29/24 3:55 AM, RonO wrote:
> On 2/28/2024 5:41 PM, erik simpson wrote:
>> On 2/28/24 3:21 PM, RonO wrote:
>>> It turns out that the common ancestor that between gibbons and the
>>> great apes had an ALU transposon jump into the intron between exon 6
>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>> transposon sequences form a stem loop structure in the RNA transcript
>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>> to a transposon insertion mutation into the TBXT gene.
>>>
>>> The insertion happened in the common ancestor of all extant apes, and
>>> has been retained by the extant ape lineages.
>>>
>>> https://www.nature.com/articles/s41586-024-07095-8
>>>
>>> The article is open access.
>>>
>>> Ron Okimoto
>>>
>> Another effect of this modification is also "Moreover, mice expressing
>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>> tail-loss evolution may have been associated with an adaptive cost of
>> the potential for neural tube defects, which continue to affect human
>> health today."
>>
>> Evidently, the advantages of losing the tail outweigh the disadvantage
>> of the neural tube defects.
>>
>
> What were the advantages?
>
> Some other simian lineages have lost their tails, but what is the
> advantage?
>
> Apes did become brachiators, but other simian lineages did not, and some
> simian lineages that adopted a similar lifestyle for supporting
> themselves in the trees, actually developed prehensile tails as a fifth
> limb for supporting themselves hanging from branches.
>
> For birds there was a selective advantage in terms of weight, and the
> tailbones degenerated and fused into a small nub.  The tail was not
> lost, and birds still have a nub that they call a pygostyle that still
> supports the muscles that control the tail movements and so the feathers
> associated with the tail.
>
> Ron Okimoto
>
I believe the article mentions that bipedalism is speculated to have
made bipedalism easier. That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential advantages. Aside from posture I can't think of what
the advantages might be. Pants are easier? (Note to literalists: I
don't seriously suggest that.)

On 2/29/24 4:29 AM, FromTheRafters wrote:
> It happens that RonO formulated :
>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>> On 2/28/24 3:21 PM, RonO wrote:
>>>> It turns out that the common ancestor that between gibbons and the
>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>> and exon 7 of the TBXT gene.  There was already an transposon
>>>> between exon 5 and exon 6.  Monkeys and apes have the ALU insertion
>>>> in the intron between exon 5 and exon 6, but the apes have the
>>>> second ALU insertion in the intron between exons 6 and 7.  So it
>>>> turns out that apes still have the exon 6 sequence in the TBXT gene,
>>>> but the two ALU transposon sequences form a stem loop structure in
>>>> the RNA transcript that messes up processing so exon 6 is skipped
>>>> and exon 5 is stuck to exon 7 in the final ape mRNA.  So part of
>>>> what makes us human is due to a transposon insertion mutation into
>>>> the TBXT gene.
>>>>
>>>> The insertion happened in the common ancestor of all extant apes,
>>>> and has been retained by the extant ape lineages.
>>>>
>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>
>>>> The article is open access.
>>>>
>>>> Ron Okimoto
>>>>
>>> Another effect of this modification is also "Moreover, mice
>>> expressing the exon-skipped Tbxt isoform develop neural tube defects,
>>> a condition that affects approximately 1 in 1,000 neonates in
>>> humans10. Thus, tail-loss evolution may have been associated with an
>>> adaptive cost of the potential for neural tube defects, which
>>> continue to affect human health today."
>>>
>>> Evidently, the advantages of losing the tail outweigh the
>>> disadvantage of the neural tube defects.
>>>
>>
>> What were the advantages?
>>
>> Some other simian lineages have lost their tails, but what is the
>> advantage?
>>
>> Apes did become brachiators, but other simian lineages did not, and
>> some simian lineages that adopted a similar lifestyle for supporting
>> themselves in the trees, actually developed prehensile tails as a
>> fifth limb for supporting themselves hanging from branches.
>>
>> For birds there was a selective advantage in terms of weight, and the
>> tailbones degenerated and fused into a small nub.  The tail was not
>> lost, and birds still have a nub that they call a pygostyle that still
>> supports the muscles that control the tail movements and so the
>> feathers associated with the tail.
>>
>> Ron Okimoto
>
> I suppose sitting is much easier without a tail.
>
> https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/
>
That can't be it. My dog has a long tail and has no trouble sitting.

erik simpson was thinking very hard :
> On 2/29/24 4:29 AM, FromTheRafters wrote:
>> It happens that RonO formulated :
>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>> It turns out that the common ancestor that between gibbons and the great
>>>>> apes had an ALU transposon jump into the intron between exon 6 and exon
>>>>> 7 of the TBXT gene.  There was already an transposon between exon 5 and
>>>>> exon 6.  Monkeys and apes have the ALU insertion in the intron between
>>>>> exon 5 and exon 6, but the apes have the second ALU insertion in the
>>>>> intron between exons 6 and 7.  So it turns out that apes still have the
>>>>> exon 6 sequence in the TBXT gene, but the two ALU transposon sequences
>>>>> form a stem loop structure in the RNA transcript that messes up
>>>>> processing so exon 6 is skipped and exon 5 is stuck to exon 7 in the
>>>>> final ape mRNA.  So part of what makes us human is due to a transposon
>>>>> insertion mutation into the TBXT gene.
>>>>>
>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>> has been retained by the extant ape lineages.
>>>>>
>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>
>>>>> The article is open access.
>>>>>
>>>>> Ron Okimoto
>>>>>
>>>> Another effect of this modification is also "Moreover, mice expressing
>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>> tail-loss evolution may have been associated with an adaptive cost of the
>>>> potential for neural tube defects, which continue to affect human health
>>>> today."
>>>>
>>>> Evidently, the advantages of losing the tail outweigh the disadvantage of
>>>> the neural tube defects.
>>>>
>>>
>>> What were the advantages?
>>>
>>> Some other simian lineages have lost their tails, but what is the
>>> advantage?
>>>
>>> Apes did become brachiators, but other simian lineages did not, and some
>>> simian lineages that adopted a similar lifestyle for supporting themselves
>>> in the trees, actually developed prehensile tails as a fifth limb for
>>> supporting themselves hanging from branches.
>>>
>>> For birds there was a selective advantage in terms of weight, and the
>>> tailbones degenerated and fused into a small nub.  The tail was not lost,
>>> and birds still have a nub that they call a pygostyle that still supports
>>> the muscles that control the tail movements and so the feathers associated
>>> with the tail.
>>>
>>> Ron Okimoto
>>
>> I suppose sitting is much easier without a tail.
>>
>> https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/
>>
> That can't be it. My dog has a long tail and has no trouble sitting.

Were we talking about dogs?

On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:

>On 2/29/24 3:55 AM, RonO wrote:
>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>> On 2/28/24 3:21 PM, RonO wrote:
>>>> It turns out that the common ancestor that between gibbons and the
>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>> to a transposon insertion mutation into the TBXT gene.
>>>>
>>>> The insertion happened in the common ancestor of all extant apes, and
>>>> has been retained by the extant ape lineages.
>>>>
>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>
>>>> The article is open access.
>>>>
>>>> Ron Okimoto
>>>>
>>> Another effect of this modification is also "Moreover, mice expressing
>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>> tail-loss evolution may have been associated with an adaptive cost of
>>> the potential for neural tube defects, which continue to affect human
>>> health today."
>>>
>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>> of the neural tube defects.
>>>
>>
>> What were the advantages?
>>
>> Some other simian lineages have lost their tails, but what is the
>> advantage?
>>
>> Apes did become brachiators, but other simian lineages did not, and some
>> simian lineages that adopted a similar lifestyle for supporting
>> themselves in the trees, actually developed prehensile tails as a fifth
>> limb for supporting themselves hanging from branches.
>>
>> For birds there was a selective advantage in terms of weight, and the
>> tailbones degenerated and fused into a small nub.  The tail was not
>> lost, and birds still have a nub that they call a pygostyle that still
>> supports the muscles that control the tail movements and so the feathers
>> associated with the tail.
>>
>> Ron Okimoto
>>
>I believe the article mentions that bipedalism is speculated to have
>made bipedalism easier.
>
No causal link there... ;-)
>
> That could be a just-so story, but mutations
>that are adopted and fixed within a population must have advantages that
>outweigh potential advantages.
>
Indubitably.
>
> Aside from posture I can't think of what
>the advantages might be. Pants are easier? (Note to literalists: I
>don't seriously suggest that.)
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

On Thu, 29 Feb 2024 13:43:34 -0500, the following appeared
in talk.origins, posted by FromTheRafters
<FTR@nomail.afraid.org>:

>erik simpson was thinking very hard :
>> On 2/29/24 4:29 AM, FromTheRafters wrote:
>>> It happens that RonO formulated :
>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>> It turns out that the common ancestor that between gibbons and the great
>>>>>> apes had an ALU transposon jump into the intron between exon 6 and exon
>>>>>> 7 of the TBXT gene.  There was already an transposon between exon 5 and
>>>>>> exon 6.  Monkeys and apes have the ALU insertion in the intron between
>>>>>> exon 5 and exon 6, but the apes have the second ALU insertion in the
>>>>>> intron between exons 6 and 7.  So it turns out that apes still have the
>>>>>> exon 6 sequence in the TBXT gene, but the two ALU transposon sequences
>>>>>> form a stem loop structure in the RNA transcript that messes up
>>>>>> processing so exon 6 is skipped and exon 5 is stuck to exon 7 in the
>>>>>> final ape mRNA.  So part of what makes us human is due to a transposon
>>>>>> insertion mutation into the TBXT gene.
>>>>>>
>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>> has been retained by the extant ape lineages.
>>>>>>
>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>
>>>>>> The article is open access.
>>>>>>
>>>>>> Ron Okimoto
>>>>>>
>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>> tail-loss evolution may have been associated with an adaptive cost of the
>>>>> potential for neural tube defects, which continue to affect human health
>>>>> today."
>>>>>
>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage of
>>>>> the neural tube defects.
>>>>>
>>>>
>>>> What were the advantages?
>>>>
>>>> Some other simian lineages have lost their tails, but what is the
>>>> advantage?
>>>>
>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>> simian lineages that adopted a similar lifestyle for supporting themselves
>>>> in the trees, actually developed prehensile tails as a fifth limb for
>>>> supporting themselves hanging from branches.
>>>>
>>>> For birds there was a selective advantage in terms of weight, and the
>>>> tailbones degenerated and fused into a small nub.  The tail was not lost,
>>>> and birds still have a nub that they call a pygostyle that still supports
>>>> the muscles that control the tail movements and so the feathers associated
>>>> with the tail.
>>>>
>>>> Ron Okimoto
>>>
>>> I suppose sitting is much easier without a tail.
>>>
>>> https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/
>>>
>> That can't be it. My dog has a long tail and has no trouble sitting.
>
>Were we talking about dogs?
>
No, about sitting with tails.
>
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

On 2/29/2024 10:05 AM, erik simpson wrote:
> On 2/29/24 3:55 AM, RonO wrote:
>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>> On 2/28/24 3:21 PM, RonO wrote:
>>>> It turns out that the common ancestor that between gibbons and the
>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>> and exon 7 of the TBXT gene.  There was already an transposon
>>>> between exon 5 and exon 6.  Monkeys and apes have the ALU insertion
>>>> in the intron between exon 5 and exon 6, but the apes have the
>>>> second ALU insertion in the intron between exons 6 and 7.  So it
>>>> turns out that apes still have the exon 6 sequence in the TBXT gene,
>>>> but the two ALU transposon sequences form a stem loop structure in
>>>> the RNA transcript that messes up processing so exon 6 is skipped
>>>> and exon 5 is stuck to exon 7 in the final ape mRNA.  So part of
>>>> what makes us human is due to a transposon insertion mutation into
>>>> the TBXT gene.
>>>>
>>>> The insertion happened in the common ancestor of all extant apes,
>>>> and has been retained by the extant ape lineages.
>>>>
>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>
>>>> The article is open access.
>>>>
>>>> Ron Okimoto
>>>>
>>> Another effect of this modification is also "Moreover, mice
>>> expressing the exon-skipped Tbxt isoform develop neural tube defects,
>>> a condition that affects approximately 1 in 1,000 neonates in
>>> humans10. Thus, tail-loss evolution may have been associated with an
>>> adaptive cost of the potential for neural tube defects, which
>>> continue to affect human health today."
>>>
>>> Evidently, the advantages of losing the tail outweigh the
>>> disadvantage of the neural tube defects.
>>>
>>
>> What were the advantages?
>>
>> Some other simian lineages have lost their tails, but what is the
>> advantage?
>>
>> Apes did become brachiators, but other simian lineages did not, and
>> some simian lineages that adopted a similar lifestyle for supporting
>> themselves in the trees, actually developed prehensile tails as a
>> fifth limb for supporting themselves hanging from branches.
>>
>> For birds there was a selective advantage in terms of weight, and the
>> tailbones degenerated and fused into a small nub.  The tail was not
>> lost, and birds still have a nub that they call a pygostyle that still
>> supports the muscles that control the tail movements and so the
>> feathers associated with the tail.
>>
>> Ron Okimoto
>>
> I believe the article mentions that bipedalism is speculated to have
> made bipedalism easier.  That could be a just-so story, but mutations
> that are adopted and fixed within a population must have advantages that
> outweigh potential advantages.  Aside from posture I can't think of what
> the advantages might be.  Pants are easier? (Note to literalists: I
> don't seriously suggest that.)
>

Bipedalism evolved long after our lineage lost it's tail. The paper
indicates that the mutation occurred over 18 million years ago, and
bipedal apes may not have started to evolve until around 8 million years
ago.

It is untrue that deleterious variants need to have some advantage to be
fixed. Wright published a paper on how deleterious chromosomal variants
could be fixed in spite of things like half the gametes being inviable
for the carriers. You just need a small enough population and genetic
drift and the worst karyotype changes could be fixed in a population.
It would be a form of sympatric speciation. Once the variant was fixed
hybrids with the normal population would be less viable.

Kangaroos kept their tails and so did bipedal dinos.

Ron Okimoto

On 2024-02-29 1:17 PM, Bob Casanova wrote:
> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
> in talk.origins, posted by erik simpson
> <eastside.erik@gmail.com>:
>
>> On 2/29/24 3:55 AM, RonO wrote:
>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>> It turns out that the common ancestor that between gibbons and the
>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>
>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>> has been retained by the extant ape lineages.
>>>>>
>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>
>>>>> The article is open access.
>>>>>
>>>>> Ron Okimoto
>>>>>
>>>> Another effect of this modification is also "Moreover, mice expressing
>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>> the potential for neural tube defects, which continue to affect human
>>>> health today."
>>>>
>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>> of the neural tube defects.
>>>>
>>>
>>> What were the advantages?
>>>
>>> Some other simian lineages have lost their tails, but what is the
>>> advantage?
>>>
>>> Apes did become brachiators, but other simian lineages did not, and some
>>> simian lineages that adopted a similar lifestyle for supporting
>>> themselves in the trees, actually developed prehensile tails as a fifth
>>> limb for supporting themselves hanging from branches.
>>>
>>> For birds there was a selective advantage in terms of weight, and the
>>> tailbones degenerated and fused into a small nub.  The tail was not
>>> lost, and birds still have a nub that they call a pygostyle that still
>>> supports the muscles that control the tail movements and so the feathers
>>> associated with the tail.
>>>
>>> Ron Okimoto
>>>
>> I believe the article mentions that bipedalism is speculated to have
>> made bipedalism easier.
>>
> No causal link there... ;-)
>>
>> That could be a just-so story, but mutations
>> that are adopted and fixed within a population must have advantages that
>> outweigh potential advantages.
>>
> Indubitably.
>>
Really? Drift is out?

>> Aside from posture I can't think of what
>> the advantages might be. Pants are easier? (Note to literalists: I
>> don't seriously suggest that.)

--
--
Don Cates ("he's a cunning rascal" PN)

On Thu, 29 Feb 2024 13:43:34 -0500, FromTheRafters
<FTR@nomail.afraid.org> wrote:

>erik simpson was thinking very hard :
>> On 2/29/24 4:29 AM, FromTheRafters wrote:
>>> It happens that RonO formulated :
>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>> It turns out that the common ancestor that between gibbons and the great
>>>>>> apes had an ALU transposon jump into the intron between exon 6 and exon
>>>>>> 7 of the TBXT gene.  There was already an transposon between exon 5 and
>>>>>> exon 6.  Monkeys and apes have the ALU insertion in the intron between
>>>>>> exon 5 and exon 6, but the apes have the second ALU insertion in the
>>>>>> intron between exons 6 and 7.  So it turns out that apes still have the
>>>>>> exon 6 sequence in the TBXT gene, but the two ALU transposon sequences
>>>>>> form a stem loop structure in the RNA transcript that messes up
>>>>>> processing so exon 6 is skipped and exon 5 is stuck to exon 7 in the
>>>>>> final ape mRNA.  So part of what makes us human is due to a transposon
>>>>>> insertion mutation into the TBXT gene.
>>>>>>
>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>> has been retained by the extant ape lineages.
>>>>>>
>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>
>>>>>> The article is open access.
>>>>>>
>>>>>> Ron Okimoto
>>>>>>
>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>> tail-loss evolution may have been associated with an adaptive cost of the
>>>>> potential for neural tube defects, which continue to affect human health
>>>>> today."
>>>>>
>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage of
>>>>> the neural tube defects.
>>>>>
>>>>
>>>> What were the advantages?
>>>>
>>>> Some other simian lineages have lost their tails, but what is the
>>>> advantage?
>>>>
>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>> simian lineages that adopted a similar lifestyle for supporting themselves
>>>> in the trees, actually developed prehensile tails as a fifth limb for
>>>> supporting themselves hanging from branches.
>>>>
>>>> For birds there was a selective advantage in terms of weight, and the
>>>> tailbones degenerated and fused into a small nub.  The tail was not lost,
>>>> and birds still have a nub that they call a pygostyle that still supports
>>>> the muscles that control the tail movements and so the feathers associated
>>>> with the tail.
>>>>
>>>> Ron Okimoto
>>>
>>> I suppose sitting is much easier without a tail.
>>>
>>> https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/
>>>
>> That can't be it. My dog has a long tail and has no trouble sitting.
>
>Were we talking about dogs?

The immediate point is about sitting with tails. The previous point
is about gibbon ancestors losing their tails. A point relevant to
both is gibbons have no problems sitting with their tails either.

--
To know less than we don't know is the nature of most knowledge

On Thu, 29 Feb 2024 08:05:05 -0800, erik simpson
<eastside.erik@gmail.com> wrote:

>On 2/29/24 3:55 AM, RonO wrote:
>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>> On 2/28/24 3:21 PM, RonO wrote:
>>>> It turns out that the common ancestor that between gibbons and the
>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>> to a transposon insertion mutation into the TBXT gene.
>>>>
>>>> The insertion happened in the common ancestor of all extant apes, and
>>>> has been retained by the extant ape lineages.
>>>>
>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>
>>>> The article is open access.
>>>>
>>>> Ron Okimoto
>>>>
>>> Another effect of this modification is also "Moreover, mice expressing
>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>> tail-loss evolution may have been associated with an adaptive cost of
>>> the potential for neural tube defects, which continue to affect human
>>> health today."
>>>
>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>> of the neural tube defects.
>>>
>>
>> What were the advantages?
>>
>> Some other simian lineages have lost their tails, but what is the
>> advantage?
>>
>> Apes did become brachiators, but other simian lineages did not, and some
>> simian lineages that adopted a similar lifestyle for supporting
>> themselves in the trees, actually developed prehensile tails as a fifth
>> limb for supporting themselves hanging from branches.
>>
>> For birds there was a selective advantage in terms of weight, and the
>> tailbones degenerated and fused into a small nub.  The tail was not
>> lost, and birds still have a nub that they call a pygostyle that still
>> supports the muscles that control the tail movements and so the feathers
>> associated with the tail.
>>
>> Ron Okimoto
>>
>I believe the article mentions that bipedalism is speculated to have
>made bipedalism easier.

If it did, perhaps it was from ChatGPT.

>That could be a just-so story, but mutations
>that are adopted and fixed within a population must have advantages that
>outweigh potential advantages. Aside from posture I can't think of what
>the advantages might be. Pants are easier? (Note to literalists: I
>don't seriously suggest that.)

--
To know less than we don't know is the nature of most knowledge

On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:

>On 2024-02-29 1:17 PM, Bob Casanova wrote:
>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>> in talk.origins, posted by erik simpson
>> <eastside.erik@gmail.com>:
>>
>>> On 2/29/24 3:55 AM, RonO wrote:
>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>
>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>> has been retained by the extant ape lineages.
>>>>>>
>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>
>>>>>> The article is open access.
>>>>>>
>>>>>> Ron Okimoto
>>>>>>
>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>> the potential for neural tube defects, which continue to affect human
>>>>> health today."
>>>>>
>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>> of the neural tube defects.
>>>>>
>>>>
>>>> What were the advantages?
>>>>
>>>> Some other simian lineages have lost their tails, but what is the
>>>> advantage?
>>>>
>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>> simian lineages that adopted a similar lifestyle for supporting
>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>> limb for supporting themselves hanging from branches.
>>>>
>>>> For birds there was a selective advantage in terms of weight, and the
>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>> supports the muscles that control the tail movements and so the feathers
>>>> associated with the tail.
>>>>
>>>> Ron Okimoto
>>>>
>>> I believe the article mentions that bipedalism is speculated to have
>>> made bipedalism easier.
>>>
>> No causal link there... ;-)
>>>
>>> That could be a just-so story, but mutations
>>> that are adopted and fixed within a population must have advantages that
>>> outweigh potential advantages.
>>>
>> Indubitably.
>>>
>Really? Drift is out?
>
No. But I didn't say it was; my comment was about advantages
vs. potential advantages, the "bird in the hand" idea. I
may, of course, be mistaken; I'm not a biologist, nor have I
ever played one on TV. And my days of staying in chain
motels/hotels are behind me.
>
>>> Aside from posture I can't think of what
>>> the advantages might be. Pants are easier? (Note to literalists: I
>>> don't seriously suggest that.)
>
>--
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

On 2024-03-01 10:49 AM, Bob Casanova wrote:
> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>
>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>> in talk.origins, posted by erik simpson
>>> <eastside.erik@gmail.com>:
>>>
>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>
>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>> has been retained by the extant ape lineages.
>>>>>>>
>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>
>>>>>>> The article is open access.
>>>>>>>
>>>>>>> Ron Okimoto
>>>>>>>
>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>> health today."
>>>>>>
>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>> of the neural tube defects.
>>>>>>
>>>>>
>>>>> What were the advantages?
>>>>>
>>>>> Some other simian lineages have lost their tails, but what is the
>>>>> advantage?
>>>>>
>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>> limb for supporting themselves hanging from branches.
>>>>>
>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>> supports the muscles that control the tail movements and so the feathers
>>>>> associated with the tail.
>>>>>
>>>>> Ron Okimoto
>>>>>
>>>> I believe the article mentions that bipedalism is speculated to have
>>>> made bipedalism easier.
>>>>
>>> No causal link there... ;-)
>>>>
>>>> That could be a just-so story, but mutations
>>>> that are adopted and fixed within a population must have advantages that
>>>> outweigh potential advantages.
>>>>
>>> Indubitably.
>>>>
>> Really? Drift is out?
>>
> No. But I didn't say it was; my comment was about advantages
> vs. potential advantages, the "bird in the hand" idea. I
> may, of course, be mistaken; I'm not a biologist, nor have I
> ever played one on TV. And my days of staying in chain
> motels/hotels are behind me.
>>
The math says that neutral mutations become fixed at the mutation rate
and even slightly deleterious mutation can occasionally become fixed.

and why is it "indubitable" some fixed mutation ("bird in the hand"?)
have advantages that outweigh that of some mutation that didn't happen?
(Assuming that "potential advantage" is due to some 'potential mutation')

>>>> Aside from posture I can't think of what
>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>> don't seriously suggest that.)
>>
>> --

--
--
Don Cates ("he's a cunning rascal" PN)

On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
talk.origins, posted by DB Cates <cates_db@hotmail.com>:

>On 2024-03-01 10:49 AM, Bob Casanova wrote:
>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>
>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>> in talk.origins, posted by erik simpson
>>>> <eastside.erik@gmail.com>:
>>>>
>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>
>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>
>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>
>>>>>>>> The article is open access.
>>>>>>>>
>>>>>>>> Ron Okimoto
>>>>>>>>
>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>> health today."
>>>>>>>
>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>> of the neural tube defects.
>>>>>>>
>>>>>>
>>>>>> What were the advantages?
>>>>>>
>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>> advantage?
>>>>>>
>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>> limb for supporting themselves hanging from branches.
>>>>>>
>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>> associated with the tail.
>>>>>>
>>>>>> Ron Okimoto
>>>>>>
>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>> made bipedalism easier.
>>>>>
>>>> No causal link there... ;-)
>>>>>
>>>>> That could be a just-so story, but mutations
>>>>> that are adopted and fixed within a population must have advantages that
>>>>> outweigh potential advantages.
>>>>>
>>>> Indubitably.
>>>>>
>>> Really? Drift is out?
>>>
>> No. But I didn't say it was; my comment was about advantages
>> vs. potential advantages, the "bird in the hand" idea. I
>> may, of course, be mistaken; I'm not a biologist, nor have I
>> ever played one on TV. And my days of staying in chain
>> motels/hotels are behind me.
>>>
>The math says that neutral mutations become fixed at the mutation rate
>and even slightly deleterious mutation can occasionally become fixed.
>
Not disputed.
>
>and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>have advantages that outweigh that of some mutation that didn't happen?
>(Assuming that "potential advantage" is due to some 'potential mutation')
>
Because an existing advantage outweighs one which doesn't
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
>
>>>>> Aside from posture I can't think of what
>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>> don't seriously suggest that.)
>>>
>>> --
>
>--
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

On 2024-03-02 10:56 PM, Bob Casanova wrote:
> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>
>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>
>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>> in talk.origins, posted by erik simpson
>>>>> <eastside.erik@gmail.com>:
>>>>>
>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>
>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>
>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>
>>>>>>>>> The article is open access.
>>>>>>>>>
>>>>>>>>> Ron Okimoto
>>>>>>>>>
>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>> health today."
>>>>>>>>
>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>> of the neural tube defects.
>>>>>>>>
>>>>>>>
>>>>>>> What were the advantages?
>>>>>>>
>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>> advantage?
>>>>>>>
>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>
>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>> associated with the tail.
>>>>>>>
>>>>>>> Ron Okimoto
>>>>>>>
>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>> made bipedalism easier.
>>>>>>
>>>>> No causal link there... ;-)
>>>>>>
>>>>>> That could be a just-so story, but mutations
>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>> outweigh potential advantages.
>>>>>>
>>>>> Indubitably.
>>>>>>
>>>> Really? Drift is out?
>>>>
>>> No. But I didn't say it was; my comment was about advantages
>>> vs. potential advantages, the "bird in the hand" idea. I
>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>> ever played one on TV. And my days of staying in chain
>>> motels/hotels are behind me.
>>>>
>> The math says that neutral mutations become fixed at the mutation rate
>> and even slightly deleterious mutation can occasionally become fixed.
>>
> Not disputed.
>>
>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>> have advantages that outweigh that of some mutation that didn't happen?
>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>
> Because an existing advantage outweighs one which doesn't
> (yet, or possibly ever) exist? Seems pretty straightforward
> to me...
>>
Why must any fixed mutation have any advantage at all. It might have a
small disadvantage, which would be *less* than a non-existent mutation. (:p

>>>>>> Aside from posture I can't think of what
>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>> don't seriously suggest that.)
>>>>
>>>> --
>>
>> --

--
--
Don Cates ("he's a cunning rascal" PN)

On 2024-02-29 16:06:49 +0000, erik simpson said:

> On 2/29/24 4:29 AM, FromTheRafters wrote:
>> It happens that RonO formulated :
>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>> It turns out that the common ancestor that between gibbons and the
>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due to
>>>>> a transposon insertion mutation into the TBXT gene.
>>>>>
>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>> has been retained by the extant ape lineages.
>>>>>
>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>
>>>>> The article is open access.
>>>>>
>>>>> Ron Okimoto
>>>>>
>>>> Another effect of this modification is also "Moreover, mice expressing
>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>> the potential for neural tube defects, which continue to affect human
>>>> health today."
>>>>
>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>> of the neural tube defects.
>>>>
>>>
>>> What were the advantages?
>>>
>>> Some other simian lineages have lost their tails, but what is the advantage?
>>>
>>> Apes did become brachiators, but other simian lineages did not, and
>>> some simian lineages that adopted a similar lifestyle for supporting
>>> themselves in the trees, actually developed prehensile tails as a fifth
>>> limb for supporting themselves hanging from branches.
>>>
>>> For birds there was a selective advantage in terms of weight, and the
>>> tailbones degenerated and fused into a small nub.  The tail was not
>>> lost, and birds still have a nub that they call a pygostyle that still
>>> supports the muscles that control the tail movements and so the
>>> feathers associated with the tail.
>>>
>>> Ron Okimoto
>>
>> I suppose sitting is much easier without a tail.
>>
>> https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6417348/
>>
> That can't be it. My dog has a long tail and has no trouble sitting.

Virtually all (non-Manx) cats likewise.

--
Athel -- French and British, living in Marseilles for 36 years; mainly
in England until 1987.

On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in
talk.origins, posted by DB Cates <cates_db@hotmail.com>:

>On 2024-03-02 10:56 PM, Bob Casanova wrote:
>> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>
>>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>
>>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>>> in talk.origins, posted by erik simpson
>>>>>> <eastside.erik@gmail.com>:
>>>>>>
>>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>>
>>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>>
>>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>>
>>>>>>>>>> The article is open access.
>>>>>>>>>>
>>>>>>>>>> Ron Okimoto
>>>>>>>>>>
>>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>>> health today."
>>>>>>>>>
>>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>>> of the neural tube defects.
>>>>>>>>>
>>>>>>>>
>>>>>>>> What were the advantages?
>>>>>>>>
>>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>>> advantage?
>>>>>>>>
>>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>>
>>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>>> associated with the tail.
>>>>>>>>
>>>>>>>> Ron Okimoto
>>>>>>>>
>>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>>> made bipedalism easier.
>>>>>>>
>>>>>> No causal link there... ;-)
>>>>>>>
>>>>>>> That could be a just-so story, but mutations
>>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>>> outweigh potential advantages.
>>>>>>>
>>>>>> Indubitably.
>>>>>>>
>>>>> Really? Drift is out?
>>>>>
>>>> No. But I didn't say it was; my comment was about advantages
>>>> vs. potential advantages, the "bird in the hand" idea. I
>>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>>> ever played one on TV. And my days of staying in chain
>>>> motels/hotels are behind me.
>>>>>
>>> The math says that neutral mutations become fixed at the mutation rate
>>> and even slightly deleterious mutation can occasionally become fixed.
>>>
>> Not disputed.
>>>
>>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>>> have advantages that outweigh that of some mutation that didn't happen?
>>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>>
>> Because an existing advantage outweighs one which doesn't
>> (yet, or possibly ever) exist? Seems pretty straightforward
>> to me...
>>>
>Why must any fixed mutation have any advantage at all. It might have a
>small disadvantage, which would be *less* than a non-existent mutation. (:p
>
OK, my assumption was that we were talking about beneficial
mutations/traits; that's what "advantage" means to me. If
advantage includes deleterious traits (IOW, DISadvantages),
I'll have to bow out.
>
>>>>>>> Aside from posture I can't think of what
>>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>>> don't seriously suggest that.)
>>>>>
>>>>> --
>>>
>>> --
>
>--
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

On 2024-03-03 1:22 PM, Bob Casanova wrote:
> On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in
> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>
>> On 2024-03-02 10:56 PM, Bob Casanova wrote:
>>> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
>>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>
>>>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>>
>>>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>>>> in talk.origins, posted by erik simpson
>>>>>>> <eastside.erik@gmail.com>:
>>>>>>>
>>>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>>>
>>>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>>>
>>>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>>>
>>>>>>>>>>> The article is open access.
>>>>>>>>>>>
>>>>>>>>>>> Ron Okimoto
>>>>>>>>>>>
>>>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>>>> health today."
>>>>>>>>>>
>>>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>>>> of the neural tube defects.
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> What were the advantages?
>>>>>>>>>
>>>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>>>> advantage?
>>>>>>>>>
>>>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>>>
>>>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>>>> associated with the tail.
>>>>>>>>>
>>>>>>>>> Ron Okimoto
>>>>>>>>>
>>>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>>>> made bipedalism easier.
>>>>>>>>
>>>>>>> No causal link there... ;-)
>>>>>>>>
>>>>>>>> That could be a just-so story, but mutations
>>>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>>>> outweigh potential advantages.
>>>>>>>>
>>>>>>> Indubitably.
>>>>>>>>
>>>>>> Really? Drift is out?
>>>>>>
>>>>> No. But I didn't say it was; my comment was about advantages
>>>>> vs. potential advantages, the "bird in the hand" idea. I
>>>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>>>> ever played one on TV. And my days of staying in chain
>>>>> motels/hotels are behind me.
>>>>>>
>>>> The math says that neutral mutations become fixed at the mutation rate
>>>> and even slightly deleterious mutation can occasionally become fixed.
>>>>
>>> Not disputed.
>>>>
>>>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>>>> have advantages that outweigh that of some mutation that didn't happen?
>>>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>>>
>>> Because an existing advantage outweighs one which doesn't
>>> (yet, or possibly ever) exist? Seems pretty straightforward
>>> to me...
>>>>
>> Why must any fixed mutation have any advantage at all. It might have a
>> small disadvantage, which would be *less* than a non-existent mutation. (:p
>>
> OK, my assumption was that we were talking about beneficial
> mutations/traits; that's what "advantage" means to me. If
> advantage includes deleterious traits (IOW, DISadvantages),
> I'll have to bow out.
>>
"That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential advantages."
is what you posted "Indubitably." to in response. The implication, to
me, is that 'fixed mutations'...'must have advantages' which is not true.

>>>>>>>> Aside from posture I can't think of what
>>>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>>>> don't seriously suggest that.)
>>>>>>
>>>>>> --
>>>>
>>>> --
>>
>> --

--
--
Don Cates ("he's a cunning rascal" PN)

On 2024-03-03 1:22 PM, Bob Casanova wrote:
> On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in
> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>
>> On 2024-03-02 10:56 PM, Bob Casanova wrote:
>>> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
>>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>
>>>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>>
>>>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>>>> in talk.origins, posted by erik simpson
>>>>>>> <eastside.erik@gmail.com>:
>>>>>>>
>>>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>>>
>>>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>>>
>>>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>>>
>>>>>>>>>>> The article is open access.
>>>>>>>>>>>
>>>>>>>>>>> Ron Okimoto
>>>>>>>>>>>
>>>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>>>> health today."
>>>>>>>>>>
>>>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>>>> of the neural tube defects.
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>> What were the advantages?
>>>>>>>>>
>>>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>>>> advantage?
>>>>>>>>>
>>>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>>>
>>>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>>>> associated with the tail.
>>>>>>>>>
>>>>>>>>> Ron Okimoto
>>>>>>>>>
>>>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>>>> made bipedalism easier.
>>>>>>>>
>>>>>>> No causal link there... ;-)
>>>>>>>>
>>>>>>>> That could be a just-so story, but mutations
>>>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>>>> outweigh potential advantages.
>>>>>>>>
>>>>>>> Indubitably.
>>>>>>>>
>>>>>> Really? Drift is out?
>>>>>>
>>>>> No. But I didn't say it was; my comment was about advantages
>>>>> vs. potential advantages, the "bird in the hand" idea. I
>>>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>>>> ever played one on TV. And my days of staying in chain
>>>>> motels/hotels are behind me.
>>>>>>
>>>> The math says that neutral mutations become fixed at the mutation rate
>>>> and even slightly deleterious mutation can occasionally become fixed.
>>>>
>>> Not disputed.
>>>>
>>>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>>>> have advantages that outweigh that of some mutation that didn't happen?
>>>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>>>
>>> Because an existing advantage outweighs one which doesn't
>>> (yet, or possibly ever) exist? Seems pretty straightforward
>>> to me...
>>>>
>> Why must any fixed mutation have any advantage at all. It might have a
>> small disadvantage, which would be *less* than a non-existent mutation. (:p
>>
> OK, my assumption was that we were talking about beneficial
> mutations/traits; that's what "advantage" means to me. If
> advantage includes deleterious traits (IOW, DISadvantages),
> I'll have to bow out.

More succinctly (I hope); It seemed to me that that we were talking
about 'fixed mutations' and the 'advantageous' bit is what I was
complaining about.

>>
>>>>>>>> Aside from posture I can't think of what
>>>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>>>> don't seriously suggest that.)
>>>>>>
>>>>>> --
>>>>
>>>> --
>>
>> --

--
--
Don Cates ("he's a cunning rascal" PN)

On Sun, 3 Mar 2024 18:09:02 -0600, the following appeared in
talk.origins, posted by DB Cates <cates_db@hotmail.com>:

>On 2024-03-03 1:22 PM, Bob Casanova wrote:
>> On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in
>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>
>>> On 2024-03-02 10:56 PM, Bob Casanova wrote:
>>>> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
>>>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>
>>>>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>>>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>>>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>>>
>>>>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>>>>> in talk.origins, posted by erik simpson
>>>>>>>> <eastside.erik@gmail.com>:
>>>>>>>>
>>>>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>>>>
>>>>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>>>>
>>>>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>>>>
>>>>>>>>>>>> The article is open access.
>>>>>>>>>>>>
>>>>>>>>>>>> Ron Okimoto
>>>>>>>>>>>>
>>>>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>>>>> health today."
>>>>>>>>>>>
>>>>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>>>>> of the neural tube defects.
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> What were the advantages?
>>>>>>>>>>
>>>>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>>>>> advantage?
>>>>>>>>>>
>>>>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>>>>
>>>>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>>>>> associated with the tail.
>>>>>>>>>>
>>>>>>>>>> Ron Okimoto
>>>>>>>>>>
>>>>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>>>>> made bipedalism easier.
>>>>>>>>>
>>>>>>>> No causal link there... ;-)
>>>>>>>>>
>>>>>>>>> That could be a just-so story, but mutations
>>>>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>>>>> outweigh potential advantages.
>>>>>>>>>
>>>>>>>> Indubitably.
>>>>>>>>>
>>>>>>> Really? Drift is out?
>>>>>>>
>>>>>> No. But I didn't say it was; my comment was about advantages
>>>>>> vs. potential advantages, the "bird in the hand" idea. I
>>>>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>>>>> ever played one on TV. And my days of staying in chain
>>>>>> motels/hotels are behind me.
>>>>>>>
>>>>> The math says that neutral mutations become fixed at the mutation rate
>>>>> and even slightly deleterious mutation can occasionally become fixed.
>>>>>
>>>> Not disputed.
>>>>>
>>>>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>>>>> have advantages that outweigh that of some mutation that didn't happen?
>>>>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>>>>
>>>> Because an existing advantage outweighs one which doesn't
>>>> (yet, or possibly ever) exist? Seems pretty straightforward
>>>> to me...
>>>>>
>>> Why must any fixed mutation have any advantage at all. It might have a
>>> small disadvantage, which would be *less* than a non-existent mutation. (:p
>>>
>> OK, my assumption was that we were talking about beneficial
>> mutations/traits; that's what "advantage" means to me. If
>> advantage includes deleterious traits (IOW, DISadvantages),
>> I'll have to bow out.
>>>
>"That could be a just-so story, but mutations
>that are adopted and fixed within a population must have advantages that
>outweigh potential advantages."
>is what you posted "Indubitably." to in response. The implication, to
>me, is that 'fixed mutations'...'must have advantages' which is not true.
>
Not my intent, which, as I noted, was that fixed advantages
outweigh potential ones. Note: advantages, which by
definition are positive. Also as noted.
>
>>>>>>>>> Aside from posture I can't think of what
>>>>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>>>>> don't seriously suggest that.)
>>>>>>>
>>>>>>> --
>>>>>
>>>>> --
>>>
>>> --
>
>--
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

On Sun, 3 Mar 2024 18:13:12 -0600, the following appeared in
talk.origins, posted by DB Cates <cates_db@hotmail.com>:

>On 2024-03-03 1:22 PM, Bob Casanova wrote:
>> On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in
>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>
>>> On 2024-03-02 10:56 PM, Bob Casanova wrote:
>>>> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
>>>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>
>>>>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>>>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>>>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>>>
>>>>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>>>>> in talk.origins, posted by erik simpson
>>>>>>>> <eastside.erik@gmail.com>:
>>>>>>>>
>>>>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>>>>
>>>>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>>>>
>>>>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>>>>
>>>>>>>>>>>> The article is open access.
>>>>>>>>>>>>
>>>>>>>>>>>> Ron Okimoto
>>>>>>>>>>>>
>>>>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>>>>> health today."
>>>>>>>>>>>
>>>>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>>>>> of the neural tube defects.
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> What were the advantages?
>>>>>>>>>>
>>>>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>>>>> advantage?
>>>>>>>>>>
>>>>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>>>>
>>>>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>>>>> associated with the tail.
>>>>>>>>>>
>>>>>>>>>> Ron Okimoto
>>>>>>>>>>
>>>>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>>>>> made bipedalism easier.
>>>>>>>>>
>>>>>>>> No causal link there... ;-)
>>>>>>>>>
>>>>>>>>> That could be a just-so story, but mutations
>>>>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>>>>> outweigh potential advantages.
>>>>>>>>>
>>>>>>>> Indubitably.
>>>>>>>>>
>>>>>>> Really? Drift is out?
>>>>>>>
>>>>>> No. But I didn't say it was; my comment was about advantages
>>>>>> vs. potential advantages, the "bird in the hand" idea. I
>>>>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>>>>> ever played one on TV. And my days of staying in chain
>>>>>> motels/hotels are behind me.
>>>>>>>
>>>>> The math says that neutral mutations become fixed at the mutation rate
>>>>> and even slightly deleterious mutation can occasionally become fixed.
>>>>>
>>>> Not disputed.
>>>>>
>>>>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>>>>> have advantages that outweigh that of some mutation that didn't happen?
>>>>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>>>>
>>>> Because an existing advantage outweighs one which doesn't
>>>> (yet, or possibly ever) exist? Seems pretty straightforward
>>>> to me...
>>>>>
>>> Why must any fixed mutation have any advantage at all. It might have a
>>> small disadvantage, which would be *less* than a non-existent mutation. (:p
>>>
>> OK, my assumption was that we were talking about beneficial
>> mutations/traits; that's what "advantage" means to me. If
>> advantage includes deleterious traits (IOW, DISadvantages),
>> I'll have to bow out.
>
>More succinctly (I hope); It seemed to me that that we were talking
>about 'fixed mutations' and the 'advantageous' bit is what I was
>complaining about.
>
OK. I keyed on the "advantages" part, which by definition
means beneficial changes (although mutations which become
fixed aren't usually egregiously disadvantageous or they
wouldn't become fixed).
>>>
>>>>>>>>> Aside from posture I can't think of what
>>>>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>>>>> don't seriously suggest that.)
>>>>>>>
>>>>>>> --
>>>>>
>>>>> --
>>>
>>> --
>
>--
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

On 2024-03-03 11:49 PM, Bob Casanova wrote:
> On Sun, 3 Mar 2024 18:13:12 -0600, the following appeared in
> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>
>> On 2024-03-03 1:22 PM, Bob Casanova wrote:
>>> On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in
>>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>
>>>> On 2024-03-02 10:56 PM, Bob Casanova wrote:
>>>>> On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared in
>>>>> talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>>
>>>>>> On 2024-03-01 10:49 AM, Bob Casanova wrote:
>>>>>>> On Thu, 29 Feb 2024 22:31:16 -0600, the following appeared
>>>>>>> in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
>>>>>>>
>>>>>>>> On 2024-02-29 1:17 PM, Bob Casanova wrote:
>>>>>>>>> On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared
>>>>>>>>> in talk.origins, posted by erik simpson
>>>>>>>>> <eastside.erik@gmail.com>:
>>>>>>>>>
>>>>>>>>>> On 2/29/24 3:55 AM, RonO wrote:
>>>>>>>>>>> On 2/28/2024 5:41 PM, erik simpson wrote:
>>>>>>>>>>>> On 2/28/24 3:21 PM, RonO wrote:
>>>>>>>>>>>>> It turns out that the common ancestor that between gibbons and the
>>>>>>>>>>>>> great apes had an ALU transposon jump into the intron between exon 6
>>>>>>>>>>>>> and exon 7 of the TBXT gene.  There was already an transposon between
>>>>>>>>>>>>> exon 5 and exon 6.  Monkeys and apes have the ALU insertion in the
>>>>>>>>>>>>> intron between exon 5 and exon 6, but the apes have the second ALU
>>>>>>>>>>>>> insertion in the intron between exons 6 and 7.  So it turns out that
>>>>>>>>>>>>> apes still have the exon 6 sequence in the TBXT gene, but the two ALU
>>>>>>>>>>>>> transposon sequences form a stem loop structure in the RNA transcript
>>>>>>>>>>>>> that messes up processing so exon 6 is skipped and exon 5 is stuck to
>>>>>>>>>>>>> exon 7 in the final ape mRNA.  So part of what makes us human is due
>>>>>>>>>>>>> to a transposon insertion mutation into the TBXT gene.
>>>>>>>>>>>>>
>>>>>>>>>>>>> The insertion happened in the common ancestor of all extant apes, and
>>>>>>>>>>>>> has been retained by the extant ape lineages.
>>>>>>>>>>>>>
>>>>>>>>>>>>> https://www.nature.com/articles/s41586-024-07095-8
>>>>>>>>>>>>>
>>>>>>>>>>>>> The article is open access.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Ron Okimoto
>>>>>>>>>>>>>
>>>>>>>>>>>> Another effect of this modification is also "Moreover, mice expressing
>>>>>>>>>>>> the exon-skipped Tbxt isoform develop neural tube defects, a condition
>>>>>>>>>>>> that affects approximately 1 in 1,000 neonates in humans10. Thus,
>>>>>>>>>>>> tail-loss evolution may have been associated with an adaptive cost of
>>>>>>>>>>>> the potential for neural tube defects, which continue to affect human
>>>>>>>>>>>> health today."
>>>>>>>>>>>>
>>>>>>>>>>>> Evidently, the advantages of losing the tail outweigh the disadvantage
>>>>>>>>>>>> of the neural tube defects.
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> What were the advantages?
>>>>>>>>>>>
>>>>>>>>>>> Some other simian lineages have lost their tails, but what is the
>>>>>>>>>>> advantage?
>>>>>>>>>>>
>>>>>>>>>>> Apes did become brachiators, but other simian lineages did not, and some
>>>>>>>>>>> simian lineages that adopted a similar lifestyle for supporting
>>>>>>>>>>> themselves in the trees, actually developed prehensile tails as a fifth
>>>>>>>>>>> limb for supporting themselves hanging from branches.
>>>>>>>>>>>
>>>>>>>>>>> For birds there was a selective advantage in terms of weight, and the
>>>>>>>>>>> tailbones degenerated and fused into a small nub.  The tail was not
>>>>>>>>>>> lost, and birds still have a nub that they call a pygostyle that still
>>>>>>>>>>> supports the muscles that control the tail movements and so the feathers
>>>>>>>>>>> associated with the tail.
>>>>>>>>>>>
>>>>>>>>>>> Ron Okimoto
>>>>>>>>>>>
>>>>>>>>>> I believe the article mentions that bipedalism is speculated to have
>>>>>>>>>> made bipedalism easier.
>>>>>>>>>>
>>>>>>>>> No causal link there... ;-)
>>>>>>>>>>
>>>>>>>>>> That could be a just-so story, but mutations
>>>>>>>>>> that are adopted and fixed within a population must have advantages that
>>>>>>>>>> outweigh potential advantages.
>>>>>>>>>>
>>>>>>>>> Indubitably.
>>>>>>>>>>
>>>>>>>> Really? Drift is out?
>>>>>>>>
>>>>>>> No. But I didn't say it was; my comment was about advantages
>>>>>>> vs. potential advantages, the "bird in the hand" idea. I
>>>>>>> may, of course, be mistaken; I'm not a biologist, nor have I
>>>>>>> ever played one on TV. And my days of staying in chain
>>>>>>> motels/hotels are behind me.
>>>>>>>>
>>>>>> The math says that neutral mutations become fixed at the mutation rate
>>>>>> and even slightly deleterious mutation can occasionally become fixed.
>>>>>>
>>>>> Not disputed.
>>>>>>
>>>>>> and why is it "indubitable" some fixed mutation ("bird in the hand"?)
>>>>>> have advantages that outweigh that of some mutation that didn't happen?
>>>>>> (Assuming that "potential advantage" is due to some 'potential mutation')
>>>>>>
>>>>> Because an existing advantage outweighs one which doesn't
>>>>> (yet, or possibly ever) exist? Seems pretty straightforward
>>>>> to me...
>>>>>>
>>>> Why must any fixed mutation have any advantage at all. It might have a
>>>> small disadvantage, which would be *less* than a non-existent mutation. (:p
>>>>
>>> OK, my assumption was that we were talking about beneficial
>>> mutations/traits; that's what "advantage" means to me. If
>>> advantage includes deleterious traits (IOW, DISadvantages),
>>> I'll have to bow out.
>>
>> More succinctly (I hope); It seemed to me that that we were talking
>> about 'fixed mutations' and the 'advantageous' bit is what I was
>> complaining about.
>>
> OK. I keyed on the "advantages" part, which by definition
> means beneficial changes (although mutations which become
> fixed aren't usually egregiously disadvantageous or they
> wouldn't become fixed).
>>>>
And I keyed on the *"must"*"have advantages".

>>>>>>>>>> Aside from posture I can't think of what
>>>>>>>>>> the advantages might be. Pants are easier? (Note to literalists: I
>>>>>>>>>> don't seriously suggest that.)
>>>>>>>>
>>>>>>>> --
>>>>>>
>>>>>> --
>>>>
>>>> --
>>
>> --