On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother effect of this modification is also "Moreover, mice expressing
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
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 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother effect of this modification is also "Moreover, mice expressing
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
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 2/29/24 3:55 AM, RonO wrote:
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother effect of this modification is also "Moreover, mice expressing
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
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
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.)
erik simpson was thinking very hard :
On 2/29/24 4:29 AM, FromTheRafters wrote:
It happens that RonO formulated :That can't be it. My dog has a long tail and has no trouble sitting.
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 upAnother 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,
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
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/
Were we talking about dogs?
On 2/29/24 3:55 AM, RonO wrote:
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother effect of this modification is also "Moreover, mice
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
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
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 Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother 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,
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
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
made bipedalism easier.
Indubitably.
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 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
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.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,
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
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
made bipedalism easier.
Indubitably.
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 Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
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.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,
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
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
made bipedalism easier.
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that >>>> outweigh potential 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.)
--
On 2024-03-01 10:49 AM, Bob Casanova wrote:
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>> made bipedalism easier.
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.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 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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that >>>>> outweigh potential 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.
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.)
--
--
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy must any fixed mutation have any advantage at all. It might have a
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>> made bipedalism easier.
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 betweenAnother 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."
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that >>>>>> outweigh potential 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.
and even slightly deleterious mutation can occasionally become fixed.
Because an existing advantage outweighs one which doesn't
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')
(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.)
--
--
On 2/29/24 4:29 AM, FromTheRafters wrote:
It happens that RonO formulated :That can't be it. My dog has a long tail and has no trouble sitting.
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 theAnother 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,
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
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 2024-03-02 10:56 PM, Bob Casanova wrote:
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy must any fixed mutation have any advantage at all. It might have a
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>> made bipedalism easier.
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 betweenAnother effect of this modification is also "Moreover, mice expressing
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
and even slightly deleterious mutation can occasionally become fixed.
Because an existing advantage outweighs one which doesn't
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') >>>
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
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.)
--
--
--
On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in"That could be a just-so story, but mutations
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-02 10:56 PM, Bob Casanova wrote:OK, my assumption was that we were talking about beneficial
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy must any fixed mutation have any advantage at all. It might have a
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate >>>> and even slightly deleterious mutation can occasionally become fixed.
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>>> made bipedalism easier.
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 6Another effect of this modification is also "Moreover, mice expressing
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
Because an existing advantage outweighs one which doesn't
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') >>>>
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
small disadvantage, which would be *less* than a non-existent mutation. (:p >>
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.)
--
--
--
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:OK, my assumption was that we were talking about beneficial
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy must any fixed mutation have any advantage at all. It might have a
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate >>>> and even slightly deleterious mutation can occasionally become fixed.
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>>> made bipedalism easier.
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 6Another effect of this modification is also "Moreover, mice expressing
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
Because an existing advantage outweighs one which doesn't
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') >>>>
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
small disadvantage, which would be *less* than a non-existent mutation. (:p >>
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.)
--
--
--
On 2024-03-03 1:22 PM, Bob Casanova wrote:
On Sat, 2 Mar 2024 23:45:12 -0600, the following appeared in"That could be a just-so story, but mutations
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-02 10:56 PM, Bob Casanova wrote:OK, my assumption was that we were talking about beneficial
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy must any fixed mutation have any advantage at all. It might have a
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate >>>>> and even slightly deleterious mutation can occasionally become fixed. >>>>>
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>>>> made bipedalism easier.
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 6Another effect of this modification is also "Moreover, mice expressing
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
Because an existing advantage outweighs one which doesn't
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') >>>>>
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
small disadvantage, which would be *less* than a non-existent mutation. (:p >>>
mutations/traits; that's what "advantage" means to me. If
advantage includes deleterious traits (IOW, DISadvantages),
I'll have to bow out.
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.)
--
--
--
--
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:OK, my assumption was that we were talking about beneficial
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy must any fixed mutation have any advantage at all. It might have a
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate >>>>> and even slightly deleterious mutation can occasionally become fixed. >>>>>
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>>>> made bipedalism easier.
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 6Another effect of this modification is also "Moreover, mice expressing
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
Because an existing advantage outweighs one which doesn't
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') >>>>>
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
small disadvantage, which would be *less* than a non-existent mutation. (:p >>>
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.)
--
--
--
--
On Sun, 3 Mar 2024 18:13:12 -0600, the following appeared inAnd I keyed on the *"must"*"have advantages".
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-03 1:22 PM, Bob Casanova wrote:OK. I keyed on the "advantages" part, which by definition
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:OK, my assumption was that we were talking about beneficial
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy 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
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate >>>>>> and even slightly deleterious mutation can occasionally become fixed. >>>>>>
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>>>>> made bipedalism easier.
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother effect of this modification is also "Moreover, mice expressing
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
Because an existing advantage outweighs one which doesn't
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')
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
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.
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.)
--
--
--
--
On 2024-03-03 11:49 PM, Bob Casanova wrote:
On Sun, 3 Mar 2024 18:13:12 -0600, the following appeared inAnd I keyed on the *"must"*"have advantages".
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-03 1:22 PM, Bob Casanova wrote:OK. I keyed on the "advantages" part, which by definition
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:OK, my assumption was that we were talking about beneficial
On Fri, 1 Mar 2024 13:10:52 -0600, the following appeared inWhy 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
talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-03-01 10:49 AM, Bob Casanova wrote:Not disputed.
On Thu, 29 Feb 2024 22:31:16 -0600, the following appearedThe math says that neutral mutations become fixed at the mutation rate >>>>>>> and even slightly deleterious mutation can occasionally become fixed. >>>>>>>
in talk.origins, posted by DB Cates <cates_db@hotmail.com>:
On 2024-02-29 1:17 PM, Bob Casanova wrote:No. But I didn't say it was; my comment was about advantages
On Thu, 29 Feb 2024 08:05:05 -0800, the following appeared >>>>>>>>>> in talk.origins, posted by erik simpsonReally? Drift is out?
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and theAnother effect of this modification is also "Moreover, mice expressing
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
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
made bipedalism easier.
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages that
outweigh potential 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.
Because an existing advantage outweighs one which doesn't
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')
(yet, or possibly ever) exist? Seems pretty straightforward
to me...
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.
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.)
--
--
--
--
--
On 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
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.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,
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
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
made bipedalism easier.
Indubitably.
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 3/9/24 7:16 AM, jillery wrote:
On Wed, 28 Feb 2024 17:21:19 -0600, RonO <rokimoto@cox.net> wrote:It seems that the Lorax also is tailless. I doubt it has anything to do with ALU.
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
In the following Youtube video, Gutsick Gibbon provides a 33-minute
anthropological perspective about the same article:
<https://www.youtube.com/watch?v=dImLB0ePWR8>
It turns out that losing their tails had happened to at least one
other primate group, between lorises and bushbabies. It would be
interesting to see if the tailless lorises have a similar ALU
transposon in the TBXT gene.
--
To know less than we don't know is the nature of most knowledge
On 01/03/2024 05:31, DB Cates wrote:
On 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have
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 transposonAnother effect of this modification is also "Moreover, mice
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
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
made bipedalism easier.
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages
that
outweigh potential advantages.
I don't know if drift is ever out but is it particularly plausible in
the case of tail loss, something that seems really rare in tetrapods?
Like, what lineages actually lost their tails - like, really lost, not "reduced" or "replaced by a non-bony appendage that serves a taily
function": frogs, apes, manx cats... bears are maybe on their way... who else?
Not to mention the article suggests tail loss could be associated with
neural tube defects, which would definitely make drift much less likely.
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.)
Not to mention the article suggests tail loss could be associated withCould you be more explicit here?
neural tube defects, which would definitely make drift much less likely.
On 2024-04-05 3:56 AM, Arkalen wrote:
On 01/03/2024 05:31, DB Cates wrote:Well, my reply was not specific to the 'tailless' idea but rather to the
On 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>> made bipedalism easier.
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 betweenAnother effect of this modification is also "Moreover, mice
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have advantages
that
outweigh potential advantages.
I don't know if drift is ever out but is it particularly plausible in
the case of tail loss, something that seems really rare in tetrapods?
Like, what lineages actually lost their tails - like, really lost, not
"reduced" or "replaced by a non-bony appendage that serves a taily
function": frogs, apes, manx cats... bears are maybe on their way...
who else?
more general statement "mutations that are adopted and fixed within a population must have advantages that outweigh potential advantages." and
the "Indubitably." reply.
However, you seem to making the claim that 'rare' fixed mutations are
less likely to be due to drift. It would seem to me that common (over
many lineages) fixed mutations, even if not identical but responsible
for very similar morphology, are almost certainly due to selection. Rare fixed mutations that have not been *demonstrated* to be associated with enhanced reproductive success are more likely to be due to drift.
Not to mention the article suggests tail loss could be associated withCould you be more explicit here?
neural tube defects, which would definitely make drift much less likely.
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 05/04/2024 23:07, DB Cates wrote:
On 2024-04-05 3:56 AM, Arkalen wrote:
On 01/03/2024 05:31, DB Cates wrote:Well, my reply was not specific to the 'tailless' idea but rather to the
On 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>> made bipedalism easier.
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 6Another effect of this modification is also "Moreover, mice
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have
advantages that
outweigh potential advantages.
I don't know if drift is ever out but is it particularly plausible in
the case of tail loss, something that seems really rare in tetrapods?
Like, what lineages actually lost their tails - like, really lost,
not "reduced" or "replaced by a non-bony appendage that serves a
taily function": frogs, apes, manx cats... bears are maybe on their
way... who else?
more general statement "mutations that are adopted and fixed within a
population must have advantages that outweigh potential advantages." and
the "Indubitably." reply.
Fair enough, I'd missed that context and I agree it was a reasonable
response to that sentence in isolation.
However, you seem to making the claim that 'rare' fixed mutations are
less likely to be due to drift. It would seem to me that common (over
many lineages) fixed mutations, even if not identical but responsible
for very similar morphology, are almost certainly due to selection. Rare
fixed mutations that have not been *demonstrated* to be associated with
enhanced reproductive success are more likely to be due to drift.
I'm not sure whether by "rare" mutation you mean "rarely found" or
"rarely occurs".
definitely much less likely to get fixed by drift than by natural
selection, because drift depends almost purely on statistics and those
are by definition not in favor of rare occurrences.
In terms of "rarely found" I don't think I'd say that; in principle both drift and selection can result in rare traits or common ones via
different dynamics.
The reason I think it speaks to drift in this case is *how rare* it is
over *how large* a population. Basically the possibilities seem to be:
- the base rate of occurrence of this mutation is extremely low - much
lower than that of mutations causing limb loss for example. It's
possible enough that the genetics & developmental pathways of tails in tetrapods make it so but it strikes me as implausible, and the mutation described in the article doesn't look like an unusually unlikely one.
- the base rate of occurrence of this mutation is higher than the number
of time it got fixed suggests, which in turn suggests the mutation is deleterious for almost all tetrapods - either because their tails are universally useful, or because this is a tricky developmental pathway to
mess with without negative impacts.
If the second is true then that leaves two non-mutually-exclusive
options for why it got fixed in the few cases it did: it was
particularly beneficial in those groups, or it wasn't deleterious for
them the way it is for other tetrapods. While the second *does* mean the trait could arise via drift, the fact it's not deleterious for them when
it is for *all other tetrapods* is itself an oddity that demands
explanation beyond "drift".
In the three clades I listed (still haven't thought of others, still interested to see if anyone does) tail loss seems pretty clearly
selective in frogs and pretty clearly due to drift in Manx cats but that latter case almost "proves the rule" - we have a clear founder effect, a
very recent trait in a small population that we can doubt would persist
over geologic time, and in a species that humans haven't been provably messing with as blatantly as dogs but still somewhat. I've never heard
of a notable bottleneck in early ape evolutionary history but it's
possible this isn't the kind of thing there would be much evidence for
or against this far out; the other two factors however are definitely
out for apes.
Actually this made me realize another reason to doubt the "base
likelihood happens to match up to 3 in all tetrapods" option: the fact
frogs went tail-less so much earlier than apes or Manx cats. Like, the
base rate is either high enough that the mutation would occur early in tetrapod history in a then-much-lower-and-less-diverse population and be available for selection to work on, OR it's low enough that it would
never drift to fixation once in non-amphibian tetrapods until apes.
Those are radically different base rates ! It's not impossible to be
fair, genetics change and the base rate could have been different in
early tetrapods vs amniotes for example. But those are some assumptions
we're adding there.
Not to mention the article suggests tail loss could be associatedCould you be more explicit here?
with neural tube defects, which would definitely make drift much less
likely.
It would make the trait deleterious, and while mildly deleterious traits
can fix through drift it's kind of core to the point of natural
selection that the probability of this happening drops sharply the more deleterious the trait is (founder effects aside).
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 05/04/2024 22:07, DB Cates wrote:
Not to mention the article suggests tail loss could be associatedCould you be more explicit here?
with neural tube defects, which would definitely make drift much less
likely.
I think that the idea is that a mutation associated with neural tube
defects is under strong enough negative selection that it would be fixed
by drift, and therefore there must be a countervailing selective
advantage to the mutation (and also selection for compensatory mutations preventing the neural tube defects).
On the other had, the mutation has been shown to be associated with
neural tube defects in one genetic background. Assuming that the
association carries over to other genetic backgrounds is a leap.
On 2024-04-06 2:55 AM, Arkalen wrote:
On 05/04/2024 23:07, DB Cates wrote:
On 2024-04-05 3:56 AM, Arkalen wrote:
On 01/03/2024 05:31, DB Cates wrote:Well, my reply was not specific to the 'tailless' idea but rather to the >>> more general statement "mutations that are adopted and fixed within a
On 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to have >>>>>>> made bipedalism easier.
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons and >>>>>>>>>> theAnother effect of this modification is also "Moreover, mice
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
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
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have
advantages that
outweigh potential advantages.
I don't know if drift is ever out but is it particularly plausible
in the case of tail loss, something that seems really rare in
tetrapods? Like, what lineages actually lost their tails - like,
really lost, not "reduced" or "replaced by a non-bony appendage that
serves a taily function": frogs, apes, manx cats... bears are maybe
on their way... who else?
population must have advantages that outweigh potential advantages." and >>> the "Indubitably." reply.
Fair enough, I'd missed that context and I agree it was a reasonable
response to that sentence in isolation.
However, you seem to making the claim that 'rare' fixed mutations are
less likely to be due to drift. It would seem to me that common (over
many lineages) fixed mutations, even if not identical but responsible
for very similar morphology, are almost certainly due to selection. Rare >>> fixed mutations that have not been *demonstrated* to be associated with
enhanced reproductive success are more likely to be due to drift.
I'm not sure whether by "rare" mutation you mean "rarely found" or
"rarely occurs".
We have a miscommunication. I was referring to *fixed* mutations only,
not mutations in general. I don't think there are such things as "rare mutations". There are some biases and special circumstances, but I think
it can be stated that mutations occur randomly without too much
violation of reality. The total number of mutations extant in a given population depends on mutation rate, genome size, and population size in
any cases meaning that every possible mutation happens regularly over
time. The *really* bad ones are eliminated early and are never observed.
Most are neutral or near neutral and are, at a very low probability,
randomly (biased by things like proximity to highly conserved areas)
fixed by drift. A significant number are deleterious and are eliminated before fixation by selection and a small number are useful in the extant environment and are positively selected and have a higher rate of fixation.
So my argument is that any *particular* mutation that becomes fixed in
one or a few populations is more likely to be due to drift while one
that becomes fixed in many diverse populations is much more likely to be
due to selection. This also applies to different mutations that have the
same or similar phenotypic effects.
In terms of "rarely occurs", such mutations areOkay, tell me where I'm wrong here and if I'm not wrong, justify your conclusion.
definitely much less likely to get fixed by drift than by natural
selection, because drift depends almost purely on statistics and those
are by definition not in favor of rare occurrences.
In terms of "rarely found" I don't think I'd say that; in principle
both drift and selection can result in rare traits or common ones via
different dynamics.
The reason I think it speaks to drift in this case is *how rare* it is
over *how large* a population. Basically the possibilities seem to be:
- the base rate of occurrence of this mutation is extremely low - much
lower than that of mutations causing limb loss for example. It's
possible enough that the genetics & developmental pathways of tails in
tetrapods make it so but it strikes me as implausible, and the
mutation described in the article doesn't look like an unusually
unlikely one.
- the base rate of occurrence of this mutation is higher than the
number of time it got fixed suggests, which in turn suggests the
mutation is deleterious for almost all tetrapods - either because
their tails are universally useful, or because this is a tricky
developmental pathway to mess with without negative impacts.
If the second is true then that leaves two non-mutually-exclusive
options for why it got fixed in the few cases it did: it was
particularly beneficial in those groups, or it wasn't deleterious for
them the way it is for other tetrapods. While the second *does* mean
the trait could arise via drift, the fact it's not deleterious for
them when it is for *all other tetrapods* is itself an oddity that
demands explanation beyond "drift".
In the three clades I listed (still haven't thought of others, still
interested to see if anyone does) tail loss seems pretty clearly
selective in frogs and pretty clearly due to drift in Manx cats but
that latter case almost "proves the rule" - we have a clear founder
effect, a very recent trait in a small population that we can doubt
would persist over geologic time, and in a species that humans haven't
been provably messing with as blatantly as dogs but still somewhat.
I've never heard of a notable bottleneck in early ape evolutionary
history but it's possible this isn't the kind of thing there would be
much evidence for or against this far out; the other two factors
however are definitely out for apes.
Actually this made me realize another reason to doubt the "base
likelihood happens to match up to 3 in all tetrapods" option: the fact
frogs went tail-less so much earlier than apes or Manx cats. Like, the
base rate is either high enough that the mutation would occur early in
tetrapod history in a then-much-lower-and-less-diverse population and
be available for selection to work on, OR it's low enough that it
would never drift to fixation once in non-amphibian tetrapods until
apes. Those are radically different base rates ! It's not impossible
to be fair, genetics change and the base rate could have been
different in early tetrapods vs amniotes for example. But those are
some assumptions we're adding there.
Not to mention the article suggests tail loss could be associatedCould you be more explicit here?
with neural tube defects, which would definitely make drift much
less likely.
It would make the trait deleterious, and while mildly deleterious
traits can fix through drift it's kind of core to the point of natural
selection that the probability of this happening drops sharply the
more deleterious the trait is (founder effects aside).
It seems to me that you are claiming that association with a severely deleterious effect would prevent fixation by drift but selection in the
same circumstances would work.
Selection will fix a severely deleterious mutation??
On 07/04/2024 00:16, DB Cates wrote:
On 2024-04-06 2:55 AM, Arkalen wrote:
On 05/04/2024 23:07, DB Cates wrote:
On 2024-04-05 3:56 AM, Arkalen wrote:
On 01/03/2024 05:31, DB Cates wrote:Well, my reply was not specific to the 'tailless' idea but rather to
On 2024-02-29 1:17 PM, Bob Casanova wrote:
On Thu, 29 Feb 2024 08:05:05 -0800, the following appearedReally? Drift is out?
in talk.origins, posted by erik simpson
<eastside.erik@gmail.com>:
On 2/29/24 3:55 AM, RonO wrote:No causal link there... ;-)
On 2/28/2024 5:41 PM, erik simpson wrote:I believe the article mentions that bipedalism is speculated to >>>>>>>> have
On 2/28/24 3:21 PM, RonO wrote:
It turns out that the common ancestor that between gibbons >>>>>>>>>>> and theAnother effect of this modification is also "Moreover, mice >>>>>>>>>> expressing
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
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
made bipedalism easier.
Indubitably.
That could be a just-so story, but mutations
that are adopted and fixed within a population must have
advantages that
outweigh potential advantages.
I don't know if drift is ever out but is it particularly plausible
in the case of tail loss, something that seems really rare in
tetrapods? Like, what lineages actually lost their tails - like,
really lost, not "reduced" or "replaced by a non-bony appendage
that serves a taily function": frogs, apes, manx cats... bears are
maybe on their way... who else?
the
more general statement "mutations that are adopted and fixed within
a population must have advantages that outweigh potential
advantages." and
the "Indubitably." reply.
Fair enough, I'd missed that context and I agree it was a reasonable
response to that sentence in isolation.
However, you seem to making the claim that 'rare' fixed mutations are
less likely to be due to drift. It would seem to me that common
(over many lineages) fixed mutations, even if not identical but
responsible
for very similar morphology, are almost certainly due to selection.
Rare
fixed mutations that have not been *demonstrated* to be associated with >>>> enhanced reproductive success are more likely to be due to drift.
I'm not sure whether by "rare" mutation you mean "rarely found" or
"rarely occurs".
We have a miscommunication. I was referring to *fixed* mutations only,
not mutations in general. I don't think there are such things as "rare
mutations". There are some biases and special circumstances, but I
think it can be stated that mutations occur randomly without too much
violation of reality. The total number of mutations extant in a given
population depends on mutation rate, genome size, and population size
in any cases meaning that every possible mutation happens regularly
over time. The *really* bad ones are eliminated early and are never
observed. Most are neutral or near neutral and are, at a very low
probability, randomly (biased by things like proximity to highly
conserved areas) fixed by drift. A significant number are deleterious
and are eliminated before fixation by selection and a small number are
useful in the extant environment and are positively selected and have
a higher rate of fixation.
So my argument is that any *particular* mutation that becomes fixed in
one or a few populations is more likely to be due to drift while one
that becomes fixed in many diverse populations is much more likely to
be due to selection. This also applies to different mutations that
have the same or similar phenotypic effects.
I'm not sure I completely follow/agree but I might be being biased by
the fact I came into this talking about a phenotypic trait not a
mutation and that gets back to how the whole thing started with a misunderstanding anyway, and it might be best to leave it at that.
In terms of "rarely occurs", such mutations areOkay, tell me where I'm wrong here and if I'm not wrong, justify your
definitely much less likely to get fixed by drift than by natural
selection, because drift depends almost purely on statistics and
those are by definition not in favor of rare occurrences.
In terms of "rarely found" I don't think I'd say that; in principle
both drift and selection can result in rare traits or common ones via
different dynamics.
The reason I think it speaks to drift in this case is *how rare* it
is over *how large* a population. Basically the possibilities seem to
be:
- the base rate of occurrence of this mutation is extremely low -
much lower than that of mutations causing limb loss for example. It's
possible enough that the genetics & developmental pathways of tails
in tetrapods make it so but it strikes me as implausible, and the
mutation described in the article doesn't look like an unusually
unlikely one.
- the base rate of occurrence of this mutation is higher than the
number of time it got fixed suggests, which in turn suggests the
mutation is deleterious for almost all tetrapods - either because
their tails are universally useful, or because this is a tricky
developmental pathway to mess with without negative impacts.
If the second is true then that leaves two non-mutually-exclusive
options for why it got fixed in the few cases it did: it was
particularly beneficial in those groups, or it wasn't deleterious for
them the way it is for other tetrapods. While the second *does* mean
the trait could arise via drift, the fact it's not deleterious for
them when it is for *all other tetrapods* is itself an oddity that
demands explanation beyond "drift".
In the three clades I listed (still haven't thought of others, still
interested to see if anyone does) tail loss seems pretty clearly
selective in frogs and pretty clearly due to drift in Manx cats but
that latter case almost "proves the rule" - we have a clear founder
effect, a very recent trait in a small population that we can doubt
would persist over geologic time, and in a species that humans
haven't been provably messing with as blatantly as dogs but still
somewhat. I've never heard of a notable bottleneck in early ape
evolutionary history but it's possible this isn't the kind of thing
there would be much evidence for or against this far out; the other
two factors however are definitely out for apes.
Actually this made me realize another reason to doubt the "base
likelihood happens to match up to 3 in all tetrapods" option: the
fact frogs went tail-less so much earlier than apes or Manx cats.
Like, the base rate is either high enough that the mutation would
occur early in tetrapod history in a then-much-lower-and-less-diverse
population and be available for selection to work on, OR it's low
enough that it would never drift to fixation once in non-amphibian
tetrapods until apes. Those are radically different base rates ! It's
not impossible to be fair, genetics change and the base rate could
have been different in early tetrapods vs amniotes for example. But
those are some assumptions we're adding there.
Not to mention the article suggests tail loss could be associatedCould you be more explicit here?
with neural tube defects, which would definitely make drift much
less likely.
It would make the trait deleterious, and while mildly deleterious
traits can fix through drift it's kind of core to the point of
natural selection that the probability of this happening drops
sharply the more deleterious the trait is (founder effects aside).
conclusion.
It seems to me that you are claiming that association with a severely
deleterious effect would prevent fixation by drift but selection in
the same circumstances would work.
Selection will fix a severely deleterious mutation??
No, selection will *weed out* a severely deleterious mutation, thus preventing it getting fixed via drift.
<snip>
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