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Old 09-16-2009, 02:36 PM   #614164  /  #1
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Default A snake with a claw?



Interesting. PZ Myers has the following explanation:

Quote:
How can this happen? Genes are pleiotropic — they tend to have lots of different functions. The genes involved in making a limb are also expressed in other places; for instance, the Hox genes that specify identity along the length of the body are also reused in specifying identity along the length of the limb. What that means is that when the snake evolved limblessness, it didn't do so by simply throwing away a collection of leg genes — it couldn't, not without also destroying genes that functioned in generating its body plan. Instead, it evolved genes or modified the regulation of genes to actively suppress limb development…but the genes to build a limb are still in the genome, and still functional, and still actively working in other ways.

What most likely happened here is that some environmental agent suppressed the suppressor, allowing the old developmental program for a limb to be re-expressed. The retention of such programs is, of course, evidence that this animal evolved from limbed ancestors.
conversely, Jerry Coyne argues for a different explanation:

Quote:
I saw this a few days ago, but refrained from posting about it because I wasn't sure if it was real. If it is, it's a great example of a re-expression of ancestral genes. But look--the limb comes out right after a bulge--as if the snake had ingested some prey object. And the limb is simply TOO perfect: digits, claws, etc. When snakes (or whales) do show atavistic limb formation, the limbs are never this good. AND, the limb appears too far anterior, I think, for it to be vestigial (look at where python "claws" are). I doubt that genetic information for limb formation would have been preserved intact so long that it could form a limb this perfect.

I suspect that this snake ingested a lizard, and that the lizard's limb simply burst through the side of the snake. I may be wrong, and I hope so, because this is great evidence for evolution.
http://scienceblogs.com/pharyngula/2...ropy_handy.php

Additional info can be found here:

http://www.telegraph.co.uk/earth/wil...-in-China.html

this may be relevant:

Quote:
"I woke up and heard a strange scratching sound. I turned on the light and saw this monster working its way along the wall using his claw," said Mrs Duan of Suining, southwest China.
What do you think?

Last edited by SteveF; 09-16-2009 at 02:40 PM.
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Old 09-16-2009, 02:44 PM   #614173  /  #2
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Lizard limb popping through the snake's abdominal wall.
That's my best guess given the limited data available.
It should also be really really easy to determine.
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Old 09-16-2009, 03:44 PM   #614232  /  #3
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That would be my (uninformed) guess.

Snakes don't always think before they eat.





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Old 09-16-2009, 04:14 PM   #614257  /  #4
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Quote:
Originally Posted by Febble View Post
Snakes don't always think before they eat.
They may not be utterly unique in this.
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Old 09-16-2009, 05:32 PM   #614312  /  #5
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That's a hindlimb, it's facing forward, and not anywhere near the pelvic girdle. It is possible it is a leg from a swallowed lizard, but it might also be a doctored specimen and thus a shitty taxidermy job.
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Old 09-17-2009, 01:59 PM   #615171  /  #6
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Quote:
Originally Posted by SteveF View Post


Interesting. PZ Myers has the following explanation:

Quote:
How can this happen? Genes are pleiotropic — they tend to have lots of different functions. The genes involved in making a limb are also expressed in other places; for instance, the Hox genes that specify identity along the length of the body are also reused in specifying identity along the length of the limb. What that means is that when the snake evolved limblessness, it didn't do so by simply throwing away a collection of leg genes — it couldn't, not without also destroying genes that functioned in generating its body plan. Instead, it evolved genes or modified the regulation of genes to actively suppress limb development…but the genes to build a limb are still in the genome, and still functional, and still actively working in other ways.

What most likely happened here is that some environmental agent suppressed the suppressor, allowing the old developmental program for a limb to be re-expressed. The retention of such programs is, of course, evidence that this animal evolved from limbed ancestors.
conversely, Jerry Coyne argues for a different explanation:

Quote:
I saw this a few days ago, but refrained from posting about it because I wasn't sure if it was real. If it is, it's a great example of a re-expression of ancestral genes. But look--the limb comes out right after a bulge--as if the snake had ingested some prey object. And the limb is simply TOO perfect: digits, claws, etc. When snakes (or whales) do show atavistic limb formation, the limbs are never this good. AND, the limb appears too far anterior, I think, for it to be vestigial (look at where python "claws" are). I doubt that genetic information for limb formation would have been preserved intact so long that it could form a limb this perfect.

I suspect that this snake ingested a lizard, and that the lizard's limb simply burst through the side of the snake. I may be wrong, and I hope so, because this is great evidence for evolution.
http://scienceblogs.com/pharyngula/2...ropy_handy.php

Additional info can be found here:

http://www.telegraph.co.uk/earth/wil...-in-China.html

this may be relevant:

Quote:
"I woke up and heard a strange scratching sound. I turned on the light and saw this monster working its way along the wall using his claw," said Mrs Duan of Suining, southwest China.
What do you think?
Myers is right...this is just an environmentally-caused defect. Darwinists must be wondering how a fully-formed leg and foot emerged -- I thought accidents were supposed to add body parts one random bit at a time. This limb is obviously part of the snake's programming. Snakes surely used to have limbs...(probably in the Garden of Eden)....and they may still possess the capability of getting them back in the right environment. All it would take is the right mental cue.
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Old 09-17-2009, 02:11 PM   #615191  /  #7
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Quote:
Originally Posted by supersport View Post
Quote:
Originally Posted by SteveF View Post


Interesting. PZ Myers has the following explanation:

Quote:
How can this happen? Genes are pleiotropic — they tend to have lots of different functions. The genes involved in making a limb are also expressed in other places; for instance, the Hox genes that specify identity along the length of the body are also reused in specifying identity along the length of the limb. What that means is that when the snake evolved limblessness, it didn't do so by simply throwing away a collection of leg genes — it couldn't, not without also destroying genes that functioned in generating its body plan. Instead, it evolved genes or modified the regulation of genes to actively suppress limb development…but the genes to build a limb are still in the genome, and still functional, and still actively working in other ways.

What most likely happened here is that some environmental agent suppressed the suppressor, allowing the old developmental program for a limb to be re-expressed. The retention of such programs is, of course, evidence that this animal evolved from limbed ancestors.
conversely, Jerry Coyne argues for a different explanation:



http://scienceblogs.com/pharyngula/2...ropy_handy.php

Additional info can be found here:

http://www.telegraph.co.uk/earth/wil...-in-China.html

this may be relevant:

Quote:
"I woke up and heard a strange scratching sound. I turned on the light and saw this monster working its way along the wall using his claw," said Mrs Duan of Suining, southwest China.
What do you think?
Myers is right...this is just an environmentally-caused defect. Darwinists must be wondering how a fully-formed leg and foot emerged -- I thought accidents were supposed to add body parts one random bit at a time.
No. You must know this by now.

Quote:
This limb is obviously part of the snake's programming. Snakes surely used to have limbs...(probably in the Garden of Eden)....and they may still possess the capability of getting them back in the right environment. All it would take is the right environmental cue
fify
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Old 09-17-2009, 02:16 PM   #615202  /  #8
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just surreal. Someone has been watching too many Godzilla movies.

And Genesis is allegorical...the struggle is within supersport...but you always were true to your cause, trolling.
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Old 09-17-2009, 02:41 PM   #615236  /  #9
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We should hybridize this thread with the "catarpillars as onychophorans" thread
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Old 09-17-2009, 03:02 PM   #615264  /  #10
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Quote:
Originally Posted by Febble View Post
Quote:
Originally Posted by supersport View Post
Quote:
Originally Posted by SteveF View Post


Interesting. PZ Myers has the following explanation:



conversely, Jerry Coyne argues for a different explanation:



http://scienceblogs.com/pharyngula/2...ropy_handy.php

Additional info can be found here:

http://www.telegraph.co.uk/earth/wil...-in-China.html

this may be relevant:



What do you think?
Myers is right...this is just an environmentally-caused defect. Darwinists must be wondering how a fully-formed leg and foot emerged -- I thought accidents were supposed to add body parts one random bit at a time.
No. You must know this by now.
not following that. do you agree with Myer's statement?
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Old 09-17-2009, 03:17 PM   #615289  /  #11
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Chernobyl snake?
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Old 09-17-2009, 03:49 PM   #615330  /  #12
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Quote:
Originally Posted by supersport View Post
Quote:
Originally Posted by Febble View Post
Quote:
Originally Posted by supersport View Post

Myers is right...this is just an environmentally-caused defect. Darwinists must be wondering how a fully-formed leg and foot emerged -- I thought accidents were supposed to add body parts one random bit at a time.
No. You must know this by now.
not following that. do you agree with Myer's statement?
Well, it looks more like the snake swallowed a lizard to me, but if it really is part of the snake, Myers' explanation seems good to me.

It's your last sentence that is wrong. Nobody is proposing that "accidents" are "supposed to add body parts one random bit at a time".
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Old 09-17-2009, 04:33 PM   #615432  /  #13
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If it is a limb from an ingested animal, why isn't it decomposing?
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Old 09-17-2009, 04:46 PM   #615450  /  #14
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Quote:
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If it is a limb from an ingested animal, why isn't it decomposing?
It's (they've?) been beaten to death with a shoe and preserved in alcohol.
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Old 09-17-2009, 04:52 PM   #615466  /  #15
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also it's a picture
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Old 09-17-2009, 05:07 PM   #615495  /  #16
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Quote:
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If it is a limb from an ingested animal, why isn't it decomposing?
Maybe it is.
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Old 09-17-2009, 05:12 PM   #615505  /  #17
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Quote:
Originally Posted by Febble View Post
That would be my (uninformed) guess.

Snakes don't always think before they eat.





]
Those pictures are very informative regarding the present subject.

The picture in the OP suggests that a lizard which had been swallowed live kept trying to scape from the insides of the snake, being able during its struggle to break the stomack and skin, from the inside out.
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Old 09-17-2009, 05:24 PM   #615526  /  #18
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The leg didn't necessarily rupture the body wall via struggle. The snake was beaten with a goddamned shoe and you can see other damage to the body elsewhere. Given that that's a hindlimb, though, and the direction in which it is facing, this fits with the idea that it's from an ingested food item.
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Old 09-17-2009, 10:43 PM   #615936  /  #19
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No. You must know this by now.
not following that. do you agree with Myer's statement?
Well, it looks more like the snake swallowed a lizard to me, but if it really is part of the snake, Myers' explanation seems good to me.

It's your last sentence that is wrong. Nobody is proposing that "accidents" are "supposed to add body parts one random bit at a time".
then what does Dawkins mean by "cumulative selection?" why does he think the eye formed by 1000 small, random (yet selected) steps?
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Old 09-17-2009, 11:13 PM   #615974  /  #20
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Quote:
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not following that. do you agree with Myer's statement?
Well, it looks more like the snake swallowed a lizard to me, but if it really is part of the snake, Myers' explanation seems good to me.

It's your last sentence that is wrong. Nobody is proposing that "accidents" are "supposed to add body parts one random bit at a time".
then what does Dawkins mean by "cumulative selection?" why does he think the eye formed by 1000 small, random (yet selected) steps?
I hate to butt in with a troll but here goes:

1) you know by now that natural selection is a non-random process.
2) the fact that evolution by natural selection is a cumulative process.
3) that cumulative selection can produce novel useful complex structures in relatively short periods of time.

Feeble, he/she is playing you against statements that are compeling and excepted at remedial evolutionary theory...but I didn't have to tell you this.
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Old 09-17-2009, 11:47 PM   #616020  /  #21
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The leg didn't necessarily rupture the body wall via struggle. The snake was beaten with a goddamned shoe and you can see other damage to the body elsewhere. Given that that's a hindlimb, though, and the direction in which it is facing, this fits with the idea that it's from an ingested food item.
Yes.

I put it to you that after beating the snake to death, they saw the lump, wondered what the snake had eaten, slit the snake with a knife, pulled out the limb, took a photo.
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Old 09-18-2009, 12:15 AM   #616050  /  #22
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Quote:
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The leg didn't necessarily rupture the body wall via struggle. The snake was beaten with a goddamned shoe and you can see other damage to the body elsewhere. Given that that's a hindlimb, though, and the direction in which it is facing, this fits with the idea that it's from an ingested food item.
Yes.

I put it to you that after beating the snake to death, they saw the lump, wondered what the snake had eaten, slit the snake with a knife, pulled out the limb, took a photo.
that's possible as well, who knows if the beating would not have created and evisceration as well.
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Old 09-18-2009, 01:55 AM   #616167  /  #23
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The "thing it ate" has the same coloration as the snake. This doesn't seem likely.
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Old 09-18-2009, 01:57 AM   #616170  /  #24
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The "thing it ate" has the same coloration as the snake. This doesn't seem likely.
Why not, we don't even have the species of the snake or range of the snake and prey?
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Old 09-18-2009, 02:00 AM   #616179  /  #25
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I actually had two semesters of herpetology, one semester regional, one omni, and I can't make out that snake. Though it was 30 years ago.
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