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Author Topic:   What mutations are needed for a particular trait (e.g. wings) to arise?
dwise1
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Posts: 4391
Joined: 05-02-2006
Member Rating: 5.6


Message 13 of 111 (345102)
08-30-2006 4:16 PM
Reply to: Message 11 by skepticfaith
08-30-2006 3:53 PM


Re: Is it possible mathematically?
quote:
Thus your analogy to the lottery is incorrect. The analogy is more like the same person winning the lottery 1000 or more times..This is why I want to KNOW approximately how much mutations is necessary ..A mathematical model could be build testing the probably of this even occurring...(the event being the evolution of the bird from a reptilian ancestor)..

I disagree. As we understand the process, evolution does not work through individuals (which implies "within a single generation"), but rather through populations of individuals over several generations. So your analogy is highly incorrect, in that you have a single individual "winning" all the mutations. A mathematical model based on that analogy would not model the event in question.

A more accurate model would be a few individuals within the population winning the lottery, which their offspring then inherit as would then their offspring (also being the offspring of others who "married into the fortune" rather than having acquired it themselves). And some lottery-inheriting descendents would at some point also marry the descendents of another lottery-winner, combining those two lottery-inheriting qualities. Such that in time, a sizable portion of the population would consist of descendents of a lottery winner.


This message is a reply to:
 Message 11 by skepticfaith, posted 08-30-2006 3:53 PM skepticfaith has responded

Replies to this message:
 Message 14 by skepticfaith, posted 08-30-2006 4:38 PM dwise1 has responded

  
dwise1
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Posts: 4391
Joined: 05-02-2006
Member Rating: 5.6


Message 26 of 111 (345230)
08-30-2006 8:25 PM
Reply to: Message 14 by skepticfaith
08-30-2006 4:38 PM


Re: Is it possible mathematically?
quote:
quote:
A more accurate model would be a few individuals within the population winning the lottery, which their offspring then inherit as would then their offspring (also being the offspring of others who "married into the fortune" rather than having acquired it themselves).

Of course of of these offspring would have to win the next lottery to aquire the next trait and so on and on.

I assume in that typo that you meant to say "Of course all of these offspring ... " -- that is the only possible actual meaning that I can think of; please correct me if I am mistaken.

As such, your statement is still wrong. Once one lottery is won, all (or at least most, depending on how we model inheritance) of the winner's descendents will have that trait and, as Gary pointed out, if it is selected for then it will spread throughout the population. As other winners appear, their descendents will also inherit and that trait will also spread and so on until many, if not most, members of the population possess most all of these traits. There is no need for every single sequential offspring to also win a lottery; if you believe that evolutionary theory says that that must be the case, then please support that claim.

quote:
For mutations to produce traits that are beneficial - the genetic code would have to be designed this way too.

How do you arrive at that idea? Remembering back to John Maynard Smith's textbook, "Evolutionary Genetics" (which deals directly with the subject of the mathematics of population genetics), the only kind of mutation that is of interest in evolution is genetic mutation (not developmental mutations, which are not heritable) and that there are basically four kinds of genetic mutation (I would need to go look that up again; it will be a few days before I'd have time). At the genetic level, there's nothing to judge a mutation as being either beneficial or detrimental; it is only through the expression of that changed genetic code that such a judgement can be made. BTW, many mutations (eg, base substitutions) are neutral, as evidenced by there being so many different versions of the same proteins. Ditto with gene duplication.

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dwise1
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Posts: 4391
Joined: 05-02-2006
Member Rating: 5.6


Message 28 of 111 (345232)
08-30-2006 8:29 PM
Reply to: Message 15 by Gary
08-30-2006 4:43 PM


Re: feathers and flight
quote:
We get a distorted view of the probabilities of these events because the fossil record is limited by various factors, like the rarity of fossilization, while modern animals all look different because they are the tips of the branches on the evolutionary tree. We don't see too many of the dead ends deep in the evolutionary tree (though we've found a few, like pterosaurs) and we also fail to see that the way things are now is only one way, out of a practically infinite number of possibilities, that things could have turned out.

Another one is that the fossil record normally only shows us the morphology and not the genetic code, the genetic code being where the actual mutations take place.

Several years ago in either Science or Nature there was an article about "green fossils", magnolia leaves that had been encased in mud such that some of their proteins survived. The morphology of the leaves showed very little if any change, whereas the protein sequences did show change.


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 Message 15 by Gary, posted 08-30-2006 4:43 PM Gary has not yet responded

  
dwise1
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Posts: 4391
Joined: 05-02-2006
Member Rating: 5.6


Message 29 of 111 (345237)
08-30-2006 8:39 PM
Reply to: Message 20 by PaulK
08-30-2006 5:56 PM


Re: Is it possible mathematically?
quote:
quote:
Thus your analogy to the lottery is incorrect. The analogy is more like the same person winning the lottery 1000 or more times..

You don't provide any argument that would justify the "thus". Not surprisingly because you are completely wrong. There is nothing equivalent to the SAME person winning the lottery multiple times. All you are doing is picking out a pattern in hindsight - which would be quite easy to do with any random data. All that is required is that SOME traits evolve which involve multiple mutations - which will be interspersed among mutations contributing to other traits. Really you are making the same mistake again. What actually happened is "very unlikely" - but like lottery winners it is very likely that you will find SOME sequences that, in hindsight are "very unlikely" - just as it is unlikely that a particular person will win the lottery - but very likely that someone will win the lottery.

Another way of looking at it when working with a population is not by finding the probability of something happening, but rather the probability of it not happening, whereupon we find the probability of it happening by subtracting that probability from one.

In a fair-sized population over multiple generation, the probability that nobody ever wins becomes becomes extremely small. That there won't be any one who inherits from multiple winners also becomes very small. Which would make the chances of the population having descendents of multiple winners very good.


This message is a reply to:
 Message 20 by PaulK, posted 08-30-2006 5:56 PM PaulK has not yet responded

  
dwise1
Member
Posts: 4391
Joined: 05-02-2006
Member Rating: 5.6


Message 106 of 111 (347474)
09-08-2006 1:32 AM
Reply to: Message 100 by Someone who cares
09-07-2006 11:38 PM


Re: Is it possible mathematically?
quote:
99.9% sounds like a good enough mathematical impossibility.
...
You know what I think personally? I think they only left that 0.1% or less to give evolutionists at least some little hope to cling to...

OK, let's take that 0.1% and do the math.

p = Probability of a beneficial mutation appearing in an individual
p = 0.1% = 0.001
q = probability it will not appear (includes harmful mutations)
q = 1 - p = 0.999

Now, for a beneficial mutation to not appear in a population of n individuals would require that it not happen n times in a row. For it to not happen over g generations would require that it not happen ng times in a row. That probability Q would be:
Q = q(ng)
And hence the probability P that a beneficial mutation would occur at least once over g generations of a population of n individuals would be:
P = 1 - Q = 1 - q(ng)

For n = 1000 and g = 100,
Q = 0.999(1000 * 100) = 3.53852*10-44
P = 1 - Q = very nearly 100% (calc rounded it off to 1; it can't handle subtracting such a small number from 1)

Now, I feel that those values of n and g are reasonable. Let's try a much smaller case and less reasonable case, such as n = 100 and g =10:

Q = 0.999(100 * 10) = 36.77%
P = 1 - Q = 63.23%
It's still twice as probable that a beneficial mutation would occur than not.

What? You make such a sweeping statement about something being "mathematically impossible", and you couldn't be bothered to do the basic math?

Well, you've let us know loud and clear how much weight your claims carry. None at all.

Consider this (as I hope your colleagues will): If the claims you make that we can check (eg, claims about science and the natural universe) all turn out to be rubbish, then how could you ever expect us to accept the claims you make that we cannot check (eg, claims about the supernatural, including claims about your God). When will you ever learn that making false claims can only work against your cause and against the Cause of Christ?

If you really did care, then you would be scrambling to clean up your act as quickly as possible. That you will undoubtedly not do that, is just more evil fruit for the Matt 7:20 test.

Edited by dwise1, : No reason given.

Edited by dwise1, : No reason given.

Edited by dwise1, : No reason given.

Edited by dwise1, : Finally cleaning up of the HTML


This message is a reply to:
 Message 100 by Someone who cares, posted 09-07-2006 11:38 PM Someone who cares has not yet responded

  
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