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Author Topic:   Stasis and Evolution
Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 28 of 61 (532850)
10-26-2009 10:22 PM
Reply to: Message 1 by Blue Jay
10-05-2009 11:17 AM


So, in summary, my position is that Arphy’s view (that stasis should not happen if things evolve) comes from an oversimplified understanding of evolution, and of the processes and functions of life.
G'day Bluejay.
Personally, I think it's a fine table!
If I have understood your post correctly, you are saying that stasis doesn't mean that evolution has stopped, that forces not reliant on phenotypic change are still at work on the population. Is that correct?
Undoubtedly this is true. I have long argued, for example, that one of the problems faced by evolution per se is that what might be termed the "Olympian" advantages (faster, stronger, higher, fiercer) are always going to count for more than the next-to-worthless budding of some speculative new anatomical feature.
I have to disagree with Arphy that if things are evolving then stasis shouldn't happen. I take your point that if the the organism is being successful, then natural selection should hold it in stasis.
Unfortunately, this creates two more significant problems for evolution.
The first is that, logically, if stasis indicates success, then phenotypic modification must indicate failure. An organism will only evolve when it is under survival stress. This makes every substantial evolutionary step a race against extinction.
The second problem is that vast amounts of time spent in stasis greatly reduce the time available to evolve. For example, Haldane's Dilemma sets a limit on human/common ancestor evolution over 10 million years of 1667 mutations. I believe Gould and Eldredge suggested that most organisms spend 99% of their life span in stasis. That would mean man would have to evolve from the common ancestor in just 17 mutations!
Stasis is obvious from the fossil record. It is observed and documented. Its ramifications for the ToE are that evolution has very little time to bring about phenotypic change, and can only do so while playing "chicken" with extinction.
Edited by Kaichos Man, : typos

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
 Message 1 by Blue Jay, posted 10-05-2009 11:17 AM Blue Jay has replied

Replies to this message:
 Message 29 by Coyote, posted 10-26-2009 10:51 PM Kaichos Man has replied
 Message 30 by Otto Tellick, posted 10-27-2009 1:31 AM Kaichos Man has replied
 Message 31 by Arphy, posted 10-27-2009 4:48 AM Kaichos Man has not replied
 Message 44 by Blue Jay, posted 10-27-2009 9:47 AM Kaichos Man has not replied

  
Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 38 of 61 (532917)
10-27-2009 8:53 AM
Reply to: Message 30 by Otto Tellick
10-27-2009 1:31 AM


Re: Haldane's Dilemma? Gould and Eldridge? What??
I did a quick wikipedia check on Haldane's dilemma
Haldane's Dilemma on Wikipedia is watched over by some troll who instantly changes the entry to a Robert Williams-friendly spiel every time someone tries to edit it.
No matter- Robert Williams is fine- in fact he accepts the figure of 1667 mutations and tries to argue that it is enough. You can google robert williams, but if you have trouble tell me and I'll find the reference.
This has no relation whatsoever to any notion of "stasis" over the life span of organisms within the population of a given species.
Sorry, this was clumsily put. I'm referring to the time span during which a species is in existence, obviously.
In any case, the next time you try to present conclusions based on quantities, you'd better "show your work" (e.g. "1% of 1667 = 17"),
Are you serious? I thought it would be insulting, not courteous!

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
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Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 39 of 61 (532918)
10-27-2009 9:09 AM
Reply to: Message 29 by Coyote
10-26-2009 10:51 PM


Likewise, when environmental conditions change quickly, then it is a race against extinction, and most species over many millions of years have lost that race. All living species today are still living exactly because they have won (so far) that race against extinction.
So where's the problem for evolution?
The problem for evolution lies in the fact that if I evolved from a microbe, then every one of my thousands of transitional ancestors must have played -and won- that game of chicken with extinction. And this is true -to a greater or lesser degree- for every creature alive today.
You will no doubt dismiss this as an "argument from incredulity", but remember that even mathematicians have established a working definition of impossibility. It's 1 to 1050. Which is interesting, because Hoyle and Wickramasinge calculated the chance creation of a single living cell as 1 to 1065.

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
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Replies to this message:
 Message 41 by bluescat48, posted 10-27-2009 9:30 AM Kaichos Man has replied
 Message 42 by Blue Jay, posted 10-27-2009 9:30 AM Kaichos Man has not replied
 Message 43 by Granny Magda, posted 10-27-2009 9:31 AM Kaichos Man has not replied
 Message 45 by Parasomnium, posted 10-27-2009 9:56 AM Kaichos Man has replied

  
Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 50 of 61 (533142)
10-29-2009 1:48 AM
Reply to: Message 45 by Parasomnium
10-27-2009 9:56 AM


Re: Someone must win
Nice avatar! I won't say anything unseemly in case its your daughter.
Clearly something with a chance of 1 in 1050 or less is still possible: the total result of two hundred coin flips in a row has a chance of about 1 in 1.6 x 1060, and I think you'll agree that it's a matter of minutes to flip a coin two hundred times. Whatever the outcome, it had a chance of 1 in 1.6 x 1060. Yet it happened.
The chance of the coin being flipped 200 times is 1. The probability of any given result is irrelevant unless it is specified. It is the same with the creation of a 1000 bp gene. The chance of 1000 base pairs existing is 1. The chance of them creating a gene that produces an enzyme (assuming there are about 20,000 possible enzymes) is 20,000 divided by 41000. Which makes it a stone cold certainty that they will create nothing at all.

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
 Message 45 by Parasomnium, posted 10-27-2009 9:56 AM Parasomnium has not replied

Replies to this message:
 Message 52 by cavediver, posted 10-29-2009 4:22 AM Kaichos Man has replied
 Message 54 by Blue Jay, posted 10-29-2009 11:06 AM Kaichos Man has replied
 Message 58 by Dr Jack, posted 11-05-2009 10:19 AM Kaichos Man has not replied

  
Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 51 of 61 (533143)
10-29-2009 1:57 AM
Reply to: Message 41 by bluescat48
10-27-2009 9:30 AM


there are 3 possibilities per mutation, harmful, neutral or beneficial thus there is a one in three chance of improving and 2 chances out of three of survival to go one step further.
Only if harmful, neutral and beneficial mutations occurred equally. The observation is that for every 175 mutations there are 3 deleterious, the other 172 being neutral or nearly neutral. Beneficial mutations are too rare, according to geneticist Motoo Kimura, to enter into calculations.

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
 Message 41 by bluescat48, posted 10-27-2009 9:30 AM bluescat48 has not replied

  
Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 53 of 61 (533184)
10-29-2009 8:03 AM
Reply to: Message 52 by cavediver
10-29-2009 4:22 AM


Re: Someone must win
Really? So what do all the other combinations produce? Nothing at all?
Not an enzyme. And I think you'd agree that for evolution from microbe to man to be possible, the odd enzyme would need to come into being.
And the probabilities show that that is marginally more probable than a talking ribosome

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
 Message 52 by cavediver, posted 10-29-2009 4:22 AM cavediver has not replied

  
Kaichos Man
Member (Idle past 4488 days)
Posts: 250
From: Tasmania, Australia
Joined: 10-03-2009


Message 55 of 61 (533483)
10-31-2009 8:42 AM
Reply to: Message 54 by Blue Jay
10-29-2009 11:06 AM


Re: Someone must win
Well, it certainly is irrelevant to this topic: stop discussing it here!
Alright. (Sulking) But I didn't start it...

"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

This message is a reply to:
 Message 54 by Blue Jay, posted 10-29-2009 11:06 AM Blue Jay has not replied

Replies to this message:
 Message 57 by Parasomnium, posted 11-01-2009 9:23 AM Kaichos Man has not replied

  
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