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Author Topic:   Has natural selection really been tested and verified?
RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 172 of 302 (537251)
11-27-2009 10:37 PM
Reply to: Message 170 by Bolder-dash
11-27-2009 9:57 PM


Re: Back to Basics - so what do you want?
Bolder-dash,
Please consider that if not one person here understands what you are trying to talk about, that the fault is in your failure to communicate what you want to talk about.
I started the thread and I said I wanted to talk about NS as it relates to EVOLUTION.!
Does this mean that you want to talk about the effects of random mutations or not?
Do you want to discuss first what evolution is, and then what natural selection means in that context? Or do you want to discuss first what natural selection is, and then how that fits into the context of evolution?
Do you agree with this definition of evolution?
Evolution is the change in the frequency distribution of hereditary traits in breeding populations from generation to generation.
If not, why not?
Do you agree with this definition of natural selection?
Natural selection - Wikipedia
quote:
Natural selection is the process by which heritable traits that make it more likely for an organism to survive and successfully reproduce become more common in a population over successive generations.
If not, why not?
Do you agree with the rest of the article as it continues
quote:
... It is a key mechanism of evolution.
The natural genetic variation within a population of organisms means that some individuals will survive and reproduce more successfully than others in their current environment. For example, the peppered moth exists in both light and dark colors in the United Kingdom, but during the industrial revolution many of the trees on which the moths rested became blackened by soot, giving the dark-colored moths an advantage in hiding from predators. This gave dark-colored moths a better chance of surviving to produce dark-colored offspring, and in just a few generations the majority of the moths were dark. Factors which affect reproductive success are also important, an issue which Charles Darwin developed in his ideas on sexual selection.
Natural selection acts on the phenotype, or the observable characteristics of an organism, but the genetic (heritable) basis of any phenotype which gives a reproductive advantage will become more common in a population (see allele frequency). Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species. In other words, natural selection is an important process (though not the only process) by which evolution takes place within a population of organisms.
Natural selection is one of the cornerstones of modern biology. The term was introduced by Darwin in his groundbreaking 1859 book On the Origin of Species,[1] in which natural selection was described by analogy to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favored for reproduction. The concept of natural selection was originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, nothing was known of modern genetics. The union of traditional Darwinian evolution with subsequent discoveries in classical and molecular genetics is termed the modern evolutionary synthesis. Natural selection remains the primary explanation for adaptive evolution.
Is there any part of that which you disagree with? What and why?
See also the section on Evolution by means of natural selection - is this what you want to discuss?
There is also a section that relates to speciation, the formation of new species and how natural selection contributes to this process. This is where diversity increases - is this what you want to discuss?
Please give us something other than complaints to work with. I'm happy to discuss these things with you, but you need to lead the discussion with some idea of what you want to accomplish and what your expectations for resolution are.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 170 by Bolder-dash, posted 11-27-2009 9:57 PM Bolder-dash has not replied

Replies to this message:
 Message 175 by Arphy, posted 11-27-2009 11:53 PM RAZD has replied
 Message 176 by ICANT, posted 11-28-2009 12:19 AM RAZD has replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 173 of 302 (537255)
11-27-2009 11:35 PM
Reply to: Message 171 by herebedragons
11-27-2009 10:06 PM


Re: speciation questions
Hi again, herebedragons,
My second problem with NS is that it doesn't appear to always select the best trait for survival. By the definition of NS ...
...traits that improve the ability of the species to survive are selected for. And while I realize that it is somewhat speculative, I am not sure that traits we find in modern examples are always the most fit for survival.
Part of the problem is that "survival of the fittest" is a misleading paradigm, and a better one would be "survival of the barely able" -- any individual that survives and breeds passes on their genes to the next generation, so just good enough is enough to pass the NS "test".
Over time the more successful ones, if repeatedly tested will prevail in higher numbers, but the marginal ones will still be a part of the mix.
The example I am thinking of is bipedalism in humans....
It might be best to take this to another topic:
Evolutionary History of Apes is one that is open, and discusses ancient ancestors. See Message 18.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 171 by herebedragons, posted 11-27-2009 10:06 PM herebedragons has seen this message but not replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 239 of 302 (537410)
11-28-2009 11:18 AM
Reply to: Message 175 by Arphy
11-27-2009 11:53 PM


Re: Back to Basics - so what do you want?
Hi Arphy, thanks for trying to arbitrate, we'll see if Bolder-dash takes it in.
Isn't "Evolution is the change in the frequency distribution of hereditary traits in breeding populations from generation to generation." really just a definition of Natural selection? I mean, this doesn't really make make any reference to variation or mutations at all? What is the difference between your definition for evolution and your definition for NS "Natural selection is the process by which heritable traits that make it more likely for an organism to survive and successfully reproduce become more common in a population over successive generations."? It seems to say the same thing except using different words. I mean "change in frequencey" is basically natural selection. Isn't it?
The change in frequency of hereditary traits is the result of natural selection, of new mutations, of genetic drift, of random disasters, etc. When this change is observed we can say evolution has occurred.
Natural selection is one of the processes that cause evolution, and it specifically addresses survival and reproductive success of individuals - a small correction to your previous post: NS operates on individual phenotypes, the developed organism that results from their genotype and developmental process (thus including environmental factors and acquired factors in the selection process).
Certainly when NS occurs then evolution occurs, but evolution can also occur without NS.
When mutations occur, and add new hereditary traits, evolution occurs.
NS causes the change in frequency, evolution results from it being changed.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 175 by Arphy, posted 11-27-2009 11:53 PM Arphy has not replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 240 of 302 (537415)
11-28-2009 11:36 AM
Reply to: Message 176 by ICANT
11-28-2009 12:19 AM


Re: Back to Basics
Hi ICANT,
I understand this to say that if you start with one species of finches with small beaks they would develop the large beaks over a period of time.
No. Evolution is a response mechanism. Change occurs in response to a change in the ecology of the species. Random mutations and genetic drift can cause some difference in the average values of a population, but it is undirected (hence "random" and "drift" terms).
It shows 14 different species of finches that have different size beaks and during wet times the small beak finches increase in number and the large beak finches decrease in number. In dry times the large beak finches increase in number and the small beak finches decrease in number.
This is natural selection: those that are better adapted to the changed ecology survive and breed better than those that are not as well adapted.
Now if that is evolution I am sold.
Natural selection is a part of evolution. One part of many.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 176 by ICANT, posted 11-28-2009 12:19 AM ICANT has replied

Replies to this message:
 Message 265 by ICANT, posted 11-29-2009 1:26 AM RAZD has replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 272 of 302 (537538)
11-29-2009 8:43 AM
Reply to: Message 265 by ICANT
11-29-2009 1:26 AM


moderator request re topic
ICANT
I am following moderator request to stick to the original topic.
For me, this means waiting to see if Bolder-dash defines what he is looking for before making any further response.
For Bolder-dash -- please define what you think constitutes "evolutionary change" so we know what you want. Please be as specific as possible.
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 265 by ICANT, posted 11-29-2009 1:26 AM ICANT has not replied

Replies to this message:
 Message 273 by Bolder-dash, posted 11-29-2009 9:49 AM RAZD has replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 277 of 302 (537556)
11-29-2009 10:40 AM
Reply to: Message 273 by Bolder-dash
11-29-2009 9:49 AM


more information please
Hi Bolder-dash, thanks, and you'll excuse me if I am a bit dense here,
Scientifically solid evidence, not conjecture because we have no other theory, that NS (through the use of RM) is responsible for the complexity of life on earth.
Evidence of what specifically.
We have evidence that change occurs through the dual mechanisms of mutation and natural selection (plus others). They are distinct processes, but the action of both is more than the action of each individually: both are needed to change a species outside the ancestral pool of hereditary traits. Mutations are needed to add new hereditary traits to the mix available for natural selection to then act, and natural selection then has the opportunity to make use of new traits through their adaption\fitness to an existing ecology. Sometimes this occurs and sometimes it does not (stasis, for example). Ultimately this two step of changes from mutations and natural selection, can result in speciation, where daughter populations become reproductively isolated, either through genetic change/s, developmental change/s or behavioral change/s in the breeding within each of the daughter populations such that they do not breed with the other anymore.
We have evidence that speciation occurs, thus dividing one breeding population into two (or more) newly isolated breeding populations.
This is sufficient to show that common ancestry is an observed (in local time) result of evolution through mutation WITH natural selection.
Common ancestry explains the diversity of life we see on earth.
What type of change are you specifically looking for.
Message 256: So now science has to show, that not only can NS (by the use of RM!) make complex body parts through a RM creating some small advantage of survivial in a population, and slowly becoming selected for, and then as it becomes a more common trait in the population, a further mutation down the bloodline could be added to that mutation (if you don't agree this is the claim the ToE, ie. Dawkins and so man others, makes for how complex body parts can be formed, please provide your own idea of how the theory claims this is possible) to eventually shape this form.
You mention complexity, can you define what you mean by complexity? Please be more specific about what you want to see. The more specific you are the easier it will be for us to provide the evidence you seek.
Enjoy.
Edited by RAZD, : added
Edited by RAZD, : changed subtitle

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 273 by Bolder-dash, posted 11-29-2009 9:49 AM Bolder-dash has not replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 286 of 302 (537585)
11-29-2009 1:29 PM
Reply to: Message 285 by Bolder-dash
11-29-2009 12:55 PM


have fun
Hi Balder-dash,
The question was-what scientific proof do we have for NS being the great cause of the evolutionary cycle that makes up the diversity of life as we know it (an inference that I think was fairly obvious).
Which was answered. Or at least the part that was obvious and applicable to actual evolution, as actually used by scientiests ...
Have you figured out what "evolutionary change" is yet? Please let us know eh?
To answer this question, you need to explain NS more fully, not just in terms of making some beaks sizes more common at one time of the year, and less common at other times- but how can it make this complete package. Can it combine with RM, with genetic drift, without some other forces to do what we see? You can believe that it can if you wish, but can you really show that it has. That IT is the thing responsible for making eyes. That IT is what makes us attracted to tall Swedish girls in small bikinis?
Once again you are using natural selection to replace all of evolution, from process to science. All of this can be explained by the theory of evolution, ToE, which involves natural selection and mutation and etc etc etc, ... but not by natural selection alone, because NS ≠ ToE, and ToE > NE.
Have you figured out what "complexity" is yet? Let us know eh?
So this was a chance for some people to explain some incredible scientific studies they had seen, which really convinced them, that there is no other way to explain what is going on around us. I say to first prove this, you have to prove that the mutations are indeed random, because if they aren't then it really isn't NS making the decision at all, it is some other force. But alas, there isn't much, and what there is is open to interpretation in any number of ways. So that in itself is an answer.
Ah yes, we failed to explain every little thing to your satisfaction with natural selection, therefore evolution is a total failure? Sorry, the logic of this eludes me.
Cheers.
Does this mean that you have decided to declared victory and are now taking your leave .... before actually dealing with the questions of what you mean by "evolutionary change" and "complexity" .... one wonders why?
Enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 285 by Bolder-dash, posted 11-29-2009 12:55 PM Bolder-dash has replied

Replies to this message:
 Message 287 by hooah212002, posted 11-29-2009 1:54 PM RAZD has seen this message but not replied
 Message 288 by Bolder-dash, posted 11-29-2009 2:31 PM RAZD has replied

RAZD
Member (Idle past 1423 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 294 of 302 (537610)
11-29-2009 4:11 PM
Reply to: Message 288 by Bolder-dash
11-29-2009 2:31 PM


Summary
Non-summation hidden. --Admin
Edited by Admin, : Hide non-summation, it's actually a reply to Bolder-dash.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 288 by Bolder-dash, posted 11-29-2009 2:31 PM Bolder-dash has not replied

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