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Author Topic:   Can mutation and selection increase information?
CRR
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Posts: 537
From: Australia
Joined: 10-19-2016
Member Rating: 1.3


Message 136 of 161 (816825)
08-11-2017 6:03 PM
Reply to: Message 133 by Taq
08-10-2017 10:37 AM


Re: random and non-random mutations
If it is a random search then it is not goal directed. Goal directed means making specific mutations to a specific gene with a known specific outcome.

You can have a search that is goal directed but can be random, systematic, or guided.

A friend of mine found a journal written by the notorious pirate, Short Jim Pewter. This recorded how SJP buried his treasure on a certain island, but unfortunately the last page with the map to the precise location was missing. Searching for this treasure is goal directed but it is also a blind search. It could be a random search or systematic but it would still be blind. When my friend started digging random holes looking for the treasure a very old parrot sitting in a tree started calling out "colder" or "warmer" with each hole. Relying on the parrot it now became a guided search and soon my friend found the treasure; 1000 jars of Vegemite. My friend took the parrot home and kept it in parrot luxury until it died.

Now consider the bacteria responding to an environmental stress. It begins to hypermutate certain regions of the genome in order to adapt. The goal is to adapt to the stress; although I don't suggest the bacteria has a conscious intention to to do this. The search space is restricted to certain parts of the genome. Within this space we assume the search is blind and random.


This message is a reply to:
 Message 133 by Taq, posted 08-10-2017 10:37 AM Taq has responded

Replies to this message:
 Message 137 by JonF, posted 08-11-2017 6:08 PM CRR has not yet responded
 Message 138 by Taq, posted 08-11-2017 6:15 PM CRR has responded

  
JonF
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Posts: 3901
Joined: 06-23-2003
Member Rating: 3.2


Message 137 of 161 (816826)
08-11-2017 6:08 PM
Reply to: Message 136 by CRR
08-11-2017 6:03 PM


Re: random and non-random mutations
Still nothing to do with the fact that the mutations are random with respect to fitness.

You need evidence, not analogies.

You admitted you have none.

You have failed.

When, you've dug yourself into a hole, what should you do?


This message is a reply to:
 Message 136 by CRR, posted 08-11-2017 6:03 PM CRR has not yet responded

  
Taq
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Posts: 7034
Joined: 03-06-2009
Member Rating: 3.8


Message 138 of 161 (816828)
08-11-2017 6:15 PM
Reply to: Message 136 by CRR
08-11-2017 6:03 PM


Re: random and non-random mutations
CRR writes:

You can have a search that is goal directed but can be random, systematic, or guided.

No, you can't. Words mean things. In biology, a goal directed mutation is one that is non-random. It is a specific change to a specific base in a specific gene that results in a specific outcome. That is what "goal directed" means in biology. A random mutation is just the opposite.

Now consider the bacteria responding to an environmental stress. It begins to hypermutate certain regions of the genome in order to adapt. The goal is to adapt to the stress; although I don't suggest the bacteria has a conscious intention to to do this. The search space is restricted to certain parts of the genome. Within this space we assume the search is blind and random.

Those are random mutations, not goal directed mutations. Increasing the random mutation rate is an increase in random mutations. Those mutations will include beneficial, neutral, and deleterious mutations. Increasing the rate at which a random number generator operates does not turn it into a non-random number generator.


This message is a reply to:
 Message 136 by CRR, posted 08-11-2017 6:03 PM CRR has responded

Replies to this message:
 Message 139 by CRR, posted 08-13-2017 2:01 AM Taq has responded

  
CRR
Member
Posts: 537
From: Australia
Joined: 10-19-2016
Member Rating: 1.3


Message 139 of 161 (816888)
08-13-2017 2:01 AM
Reply to: Message 138 by Taq
08-11-2017 6:15 PM


Re: random and non-random mutations
In biology, a goal directed mutation is one that is non-random. It is a specific change to a specific base in a specific gene that results in a specific outcome. That is what "goal directed" means in biology.

Perhaps it does but I couldn't find it in a glossary of biological terms.
Perhaps you could supply a link to a suitable definition.

However I think you might be confusing "goal directed search" with a "guided search". In fact if the organism can go to a specific base in a specific gene to get a specific outcome it's not a search at all.

I tried to show the differences in my story about Short Jim Pewter.

Another example is the immune system. In response to an infection the immune system starts producing many variations looking for an antibody for the invader. This is goal directed but the immune system can't go directly to the specific mutation that will produce the antibody and it might have to use a blind search to find an antibody that works. (Not a perfect analogy since the immune system starts with a library of antibodies that have worked for past infections.)

In a blind search humans will often use a systematic search instead of a purely random search but this is still different to a guided search in which information is supplied to enable the search target to be reached more efficiently. A blind search can still have a goal as in "A blind search (also called an uninformed search) is a search that has no information about its domain. The only thing that a blind search can do is distinguish a non-goal state from a goal state." ref.


This message is a reply to:
 Message 138 by Taq, posted 08-11-2017 6:15 PM Taq has responded

Replies to this message:
 Message 140 by JonF, posted 08-13-2017 8:23 AM CRR has responded
 Message 144 by Taq, posted 08-14-2017 11:08 AM CRR has not yet responded

  
JonF
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Posts: 3901
Joined: 06-23-2003
Member Rating: 3.2


Message 140 of 161 (816903)
08-13-2017 8:23 AM
Reply to: Message 139 by CRR
08-13-2017 2:01 AM


Re: random and non-random mutations
The issue is with the word "directed".

quote:
1. guided, regulated, or managed:a carefully directed program.
2. subject to direction, guidance, regulation, etc.

All the evidence we have is there is nothing guiding, regulating, or managing the mutations we are discussing.

Got any evidence for your position?


This message is a reply to:
 Message 139 by CRR, posted 08-13-2017 2:01 AM CRR has responded

Replies to this message:
 Message 141 by CRR, posted 08-13-2017 7:21 PM JonF has responded

  
CRR
Member
Posts: 537
From: Australia
Joined: 10-19-2016
Member Rating: 1.3


Message 141 of 161 (816933)
08-13-2017 7:21 PM
Reply to: Message 140 by JonF
08-13-2017 8:23 AM


Re: random and non-random mutations
goal–directed: aimed toward a goal or toward completion of a task.

As I have explained a search can have a goal while still being a blind search, as opposed to a guided search. And a blind search can be a random search.
(Maybe I should be writing "goal-directed" rather than "goal directed".)


This message is a reply to:
 Message 140 by JonF, posted 08-13-2017 8:23 AM JonF has responded

Replies to this message:
 Message 142 by JonF, posted 08-13-2017 7:44 PM CRR has not yet responded
 Message 143 by New Cat's Eye, posted 08-13-2017 10:47 PM CRR has not yet responded
 Message 145 by Taq, posted 08-14-2017 11:09 AM CRR has responded
 Message 146 by Percy, posted 08-15-2017 7:39 AM CRR has not yet responded

  
JonF
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Posts: 3901
Joined: 06-23-2003
Member Rating: 3.2


(1)
Message 142 of 161 (816934)
08-13-2017 7:44 PM
Reply to: Message 141 by CRR
08-13-2017 7:21 PM


Re: random and non-random mutations
The subject is not the universe of possible searches. The subject is a particular "search" (not everyone thinks it is a search).

Mutation rate can increase under stress. Do you have any evidence those mutations are not random with respect to fitness?

{Rhetorical question. You have admitted you don't. So all this current blathering is off topic and pointless.)


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 Message 141 by CRR, posted 08-13-2017 7:21 PM CRR has not yet responded

  
New Cat's Eye
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Posts: 11675
From: near St. Louis
Joined: 01-27-2005
Member Rating: 2.6


Message 143 of 161 (816938)
08-13-2017 10:47 PM
Reply to: Message 141 by CRR
08-13-2017 7:21 PM


Re: random and non-random mutations
goal–directed: aimed toward a goal or toward completion of a task.
As I have explained a search can have a goal while still being a blind search, as opposed to a guided search. And a blind search can be a random search.
(Maybe I should be writing "goal-directed" rather than "goal directed".)

That's cool, but if you're talking about the Theory of Evolution, you should understand that when mutations are referred to as random, it means with respect to fitness.

Going on about some other kind of randomness isn't talking about the Theory of Evolution.

Like I said, it's cool, postulate all you want. Just don't act like your talking about what the theory says.


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 Message 141 by CRR, posted 08-13-2017 7:21 PM CRR has not yet responded

  
Taq
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Posts: 7034
Joined: 03-06-2009
Member Rating: 3.8


(1)
Message 144 of 161 (816972)
08-14-2017 11:08 AM
Reply to: Message 139 by CRR
08-13-2017 2:01 AM


Re: random and non-random mutations
CRR writes:

Perhaps it does but I couldn't find it in a glossary of biological terms.
Perhaps you could supply a link to a suitable definition.

If you are using them to mean the very same thing, then just use the term "random mutations".

However I think you might be confusing "goal directed search" with a "guided search". In fact if the organism can go to a specific base in a specific gene to get a specific outcome it's not a search at all.

If mutations are produced without any meaningful connection to what would help or hurt the organism, then it is random with respect to fitness.

Another example is the immune system. In response to an infection the immune system starts producing many variations looking for an antibody for the invader. This is goal directed but the immune system can't go directly to the specific mutation that will produce the antibody and it might have to use a blind search to find an antibody that works. (Not a perfect analogy since the immune system starts with a library of antibodies that have worked for past infections.)

Those are random mutations. It is not goal directed mutagenesis.


This message is a reply to:
 Message 139 by CRR, posted 08-13-2017 2:01 AM CRR has not yet responded

  
Taq
Member
Posts: 7034
Joined: 03-06-2009
Member Rating: 3.8


(1)
Message 145 of 161 (816973)
08-14-2017 11:09 AM
Reply to: Message 141 by CRR
08-13-2017 7:21 PM


Re: random and non-random mutations
CRR writes:

goal–directed: aimed toward a goal or toward completion of a task.
As I have explained a search can have a goal while still being a blind search, as opposed to a guided search. And a blind search can be a random search.
(Maybe I should be writing "goal-directed" rather than "goal directed".)

There is already a term that describes this process. It is called random mutagenesis.

All you are doing is redefining terms to make them sound more guided when they aren't.


This message is a reply to:
 Message 141 by CRR, posted 08-13-2017 7:21 PM CRR has responded

Replies to this message:
 Message 147 by CRR, posted 08-16-2017 6:51 PM Taq has responded

  
Percy
Member
Posts: 15706
From: New Hampshire
Joined: 12-23-2000
Member Rating: 2.6


Message 146 of 161 (817033)
08-15-2017 7:39 AM
Reply to: Message 141 by CRR
08-13-2017 7:21 PM


Re: random and non-random mutations
Mutations occur randomly with respect to fitness. It's natural selection that's goal-directed with respect to fitness.

--Percy


This message is a reply to:
 Message 141 by CRR, posted 08-13-2017 7:21 PM CRR has not yet responded

    
CRR
Member
Posts: 537
From: Australia
Joined: 10-19-2016
Member Rating: 1.3


Message 147 of 161 (817345)
08-16-2017 6:51 PM
Reply to: Message 145 by Taq
08-14-2017 11:09 AM


Re: random and non-random mutations
Taq writes:

CRR writes:

goal–directed: aimed toward a goal or toward completion of a task.
As I have explained a search can have a goal while still being a blind search, as opposed to a guided search. And a blind search can be a random search.
(Maybe I should be writing "goal-directed" rather than "goal directed".)

There is already a term that describes this process. It is called random mutagenesis.

All you are doing is redefining terms to make them sound more guided when they aren't.

I have already made the distinction between a goal-directed search and a guided search. A search can be goal-directed and unguided, completely random, at the same time. The mistake you are making is to assume that a random search is necessarily not goal-directed. Rather than "redefining terms" I am using already established terms in their normal way.

But the question is Can mutation and selection increase information?


This message is a reply to:
 Message 145 by Taq, posted 08-14-2017 11:09 AM Taq has responded

Replies to this message:
 Message 148 by JonF, posted 08-16-2017 7:42 PM CRR has responded
 Message 151 by Percy, posted 08-17-2017 8:49 AM CRR has responded
 Message 152 by Taq, posted 08-17-2017 11:15 AM CRR has not yet responded

  
JonF
Member
Posts: 3901
Joined: 06-23-2003
Member Rating: 3.2


Message 148 of 161 (817349)
08-16-2017 7:42 PM
Reply to: Message 147 by CRR
08-16-2017 6:51 PM


Re: random and non-random mutations
It doesn't matter what any "random" search may or may not be. We are discussing one particular "search". You have admitted you have no evidence that particular "search" is related to a goal in any way.

Blathering on about anything other than that particular "search" is pointless. Please address the subject.


This message is a reply to:
 Message 147 by CRR, posted 08-16-2017 6:51 PM CRR has responded

Replies to this message:
 Message 149 by CRR, posted 08-16-2017 9:36 PM JonF has responded

  
CRR
Member
Posts: 537
From: Australia
Joined: 10-19-2016
Member Rating: 1.3


Message 149 of 161 (817357)
08-16-2017 9:36 PM
Reply to: Message 148 by JonF
08-16-2017 7:42 PM


Re: random and non-random mutations
You have admitted you have no evidence that particular "search" is related to a goal in any way.

Incorrect.

This is relating to hypermutation of selected areas of the genome in response to an environmental stress trigger.
It appears this is a mechanism to adapt to the event and that makes it goal-directed; the goal being to adapt. I also pointed out that some parts of the genome are preferentially targeted for mutation rather than being random across the entire genome. It might be that the mutations within those target areas are random, but maybe not. At this stage I don't think there is specific evidence either way.


This message is a reply to:
 Message 148 by JonF, posted 08-16-2017 7:42 PM JonF has responded

Replies to this message:
 Message 150 by JonF, posted 08-17-2017 8:45 AM CRR has not yet responded

  
JonF
Member
Posts: 3901
Joined: 06-23-2003
Member Rating: 3.2


Message 150 of 161 (817370)
08-17-2017 8:45 AM
Reply to: Message 149 by CRR
08-16-2017 9:36 PM


Re: random and non-random mutations
You have admitted you have no evidence that particular "search" is related to a goal in any way.

Incorrect.

O rly?

Similarly when mutations increase in selected regions in response to an environmental stress there is a good chance that the goal is to adapt to the stressor, even if the mutations are essentially random. Since the hypermutation targets certain areas it is likely these areas have a higher probability of producing a favourable mutation. Conversely hypermutation in other areas of the genome are less likely to produce a mutation favourable to adaptation.

This is a hypothesis. There is insufficient evidence at this time to accept it, but there is even less evidence to reject it.

{Of course there is lots of evidence to reject it; ignoring it doesn't make that go away).

It appears this is a mechanism to adapt to the event and that makes it goal-directed; the goal being to adapt.

For which there is absolutely no evidence. I already posted one paper demonstrating your hypothesis is false; how many more shall I post?

At this stage I don't think there is specific evidence either way.

Another admission of having no evidence for your claim.


This message is a reply to:
 Message 149 by CRR, posted 08-16-2017 9:36 PM CRR has not yet responded

  
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