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Author Topic:   How do you define the word Evolution?
Taq
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Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


Message 861 of 936 (813683)
06-29-2017 5:46 PM
Reply to: Message 860 by caffeine
06-29-2017 4:23 PM


Re: Polyploidy -- evolution by doubling the genome
caffeine writes:
The reason Taq is so inordinately fond of these mice as an example of evolution, though, is that there is not one allele for dark colouration.
I would put that 3rd on the list of reasons I like this example. The 1st reason is that they were able to correlate the phenotypic change to mutations in a specific gene. The 2nd reason is that we know that this mutation could not have existed in ancestral pocket mice because the basalt outcroppings appeared in just the last few million years. Prior to these volcanic eruptions there were only brown mice because the black allele would have been selected against and removed from the population.

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Taq
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Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


Message 863 of 936 (813686)
06-29-2017 5:50 PM
Reply to: Message 862 by Faith
06-29-2017 5:48 PM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
In any case it is still true that to get one color means losing the other colors.
Getting a new color does not require the loss of the other color, as you have tried to claim.

This message is a reply to:
 Message 862 by Faith, posted 06-29-2017 5:48 PM Faith has replied

Replies to this message:
 Message 864 by Faith, posted 06-29-2017 5:56 PM Taq has replied

  
Taq
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Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 865 of 936 (813691)
06-29-2017 6:03 PM
Reply to: Message 864 by Faith
06-29-2017 5:56 PM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
In the population that must be black for the sake of survival it does mean either losing or severely reducing other colors.
But you don't need to eliminate the other color in order to have black mice, which is what you claimed before. It is the mutations that produce black fur, not the removal of the brown allele.

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 Message 864 by Faith, posted 06-29-2017 5:56 PM Faith has replied

Replies to this message:
 Message 866 by Faith, posted 06-29-2017 6:09 PM Taq has replied

  
Taq
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Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


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Message 869 of 936 (813742)
06-30-2017 11:53 AM
Reply to: Message 866 by Faith
06-29-2017 6:09 PM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
But for the black fur to characterize the whole population in the black environment . . .
That is not what we are talking about. You said that natural selection produces the black fur. This is false. It is mutations that produced the black fur, not selection.

This message is a reply to:
 Message 866 by Faith, posted 06-29-2017 6:09 PM Faith has replied

Replies to this message:
 Message 871 by Faith, posted 06-30-2017 11:59 AM Taq has replied

  
Taq
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Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


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Message 870 of 936 (813743)
06-30-2017 11:56 AM
Reply to: Message 868 by CRR
06-30-2017 4:27 AM


Re: Polyploidy -- evolution by doubling the genome
CRR writes:
Coat colour is controlled in large part by the interaction of two proteins, the melanocortin-1-receptor (MC1R) and the agouti-signaling protein. The mutations in mcr1 prevent this interaction resulting in dark coats. So it's not that the mice have gained the ability to produce dark coats but rather they have lost control of the colour resulting in dark coats. So it is a loss of function mutation; one that is beneficial when the mice live on dark rocks.
Dark coat colors are a gain in function:
"In the laboratory mouse, loss-of-function mutations at Mc1r are recessive and result in light color, whereas gain-of-function alleles are dominant and result in dark color (16)."
Just a moment...

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 Message 868 by CRR, posted 06-30-2017 4:27 AM CRR has replied

Replies to this message:
 Message 920 by CRR, posted 07-06-2017 6:49 PM Taq has replied

  
Taq
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Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


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Message 872 of 936 (813748)
06-30-2017 12:06 PM
Reply to: Message 871 by Faith
06-30-2017 11:59 AM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
I mean and always mean that A WHOLE POPULATION of a particular phenotype is produced by selection, not the black fur itself.
Would you also agree that black fur color was produced by a mutation, and that mutation is beneficial?
I've said over and over that it doesn't matter how the genetic diversity is produced, whether by mutation or built in alleles, when you have evolution, meaning the production of a population of new phenotypes, it can only happen by the reduction of genetic diversity.
At one point there was just brown mice. Due to a mutation, there is now black and brown mice. This is evolution. How is this a reduction in genetic diversity when you go from one phenotype to two phenotypes?

This message is a reply to:
 Message 871 by Faith, posted 06-30-2017 11:59 AM Faith has replied

Replies to this message:
 Message 873 by Faith, posted 06-30-2017 4:43 PM Taq has replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 912 of 936 (814255)
07-05-2017 12:41 PM
Reply to: Message 873 by Faith
06-30-2017 4:43 PM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
I don't know what to think of the mutation theory. It may be a mutation, but it doesn't matter.
It does matter. The paper lists the mutations in the Mcr1 gene that are associated with black fur. Do you have any reason to doubt that these mutations are the cause for black fur in these mice? Why are you so reluctant to accept these mutations as the source of black fur?
Again, it's the selection that reduces the genetic diversity, and it's the selection that creates the new population, or in some cases "species." In the new population there is only the one phenotype.
There are two phenotypes in this population where there used to be one. You keep ignoring this fact.

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 Message 873 by Faith, posted 06-30-2017 4:43 PM Faith has not replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


Message 913 of 936 (814257)
07-05-2017 12:45 PM
Reply to: Message 875 by Faith
06-30-2017 11:21 PM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
No no no no no. Loss of genetic diversity is necessary to evolution, to the formation of new phenotypes, new species etc.
These mice did not have lose their brown fur in order to evolve black fur. Before the mutations there was just brown fur. After the mutations, there are now mice with black and brown fur. How is this not an increase in genetic diversity?
you still have to reduce or get rid of the genetic material that is not part of the new phenotype/species.
Reduction of one allele is now considered a loss in genetic diversity? Really?
Before mutations: 100% brown allele
After mutations: 10% black fur, 90% brown fur
You are saying that after the mutations there is less genetic diversity?

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 Message 875 by Faith, posted 06-30-2017 11:21 PM Faith has not replied

Replies to this message:
 Message 916 by RAZD, posted 07-05-2017 1:26 PM Taq has replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 914 of 936 (814258)
07-05-2017 12:46 PM
Reply to: Message 886 by Faith
07-01-2017 12:42 PM


Re: Faith: Macroevolution is any new population beyond the boundary of the Kind
Faith writes:
My definition of the Kind is functional, defined by the point at which evolution runs out of genetic diversity.
Evolution never runs out of genetic diversity because new alleles are created by mutations all of the time.

This message is a reply to:
 Message 886 by Faith, posted 07-01-2017 12:42 PM Faith has not replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 915 of 936 (814259)
07-05-2017 12:48 PM
Reply to: Message 880 by Faith
07-01-2017 9:14 AM


Re: Polyploidy -- evolution by doubling the genome
Faith writes:
You don't need mutation for adaptations either, just new combinations of existing alleles.
What combinations of existing human alleles will produce an elephant?

This message is a reply to:
 Message 880 by Faith, posted 07-01-2017 9:14 AM Faith has not replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 917 of 936 (814273)
07-05-2017 3:10 PM
Reply to: Message 916 by RAZD
07-05-2017 1:26 PM


Re: Polyploidy -- evolution by doubling the genome
RAZD writes:
And ... black is dominant ... so, the Hardy-Weinberg equation gives us:
That was more of a guesstimate. The actual number is probably a bit lower since the black basalt outcroppings make up a small percentage of their overall range.
Edited by Taq, : No reason given.

This message is a reply to:
 Message 916 by RAZD, posted 07-05-2017 1:26 PM RAZD has replied

Replies to this message:
 Message 918 by RAZD, posted 07-06-2017 6:10 AM Taq has replied

  
Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 922 of 936 (814345)
07-07-2017 10:58 AM
Reply to: Message 920 by CRR
07-06-2017 6:49 PM


Re: MC1R gene and the agouti-signaling protein
CRR writes:
I was talking about loss of function between the MC1R gene and the agouti-signaling protein.
They are talking gain/loss of function as it relates to coat colour..
Dominant/recessive does not determine gain/loss of functional information. A normal light switch can be turned on or off. A broken light switch can result in a light permanently on (dominant) or permanently off (recessive); but the switch is broken in either case. Similarly with the MC1R gene.
You are claiming that any change, no matter what it is, is a broken switch. That is just denial.

This message is a reply to:
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Taq
Member
Posts: 9970
Joined: 03-06-2009
Member Rating: 5.6


(1)
Message 923 of 936 (814346)
07-07-2017 10:59 AM
Reply to: Message 918 by RAZD
07-06-2017 6:10 AM


Re: SRe: Polyploidy -- evolution by doubling the genome
RAZD writes:
So 90% of statistics used in arguments are made up on the spot?
+/- 1.8%. Don't forget the standard deviation.

This message is a reply to:
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