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Author Topic:   Has natural selection really been tested and verified?
Peg
Member (Idle past 4929 days)
Posts: 2703
From: melbourne, australia
Joined: 11-22-2008


Message 151 of 302 (537130)
11-27-2009 4:54 AM
Reply to: Message 150 by Huntard
11-27-2009 4:43 AM


Re: Here's mine
Huntard writes:
No, the DNA is inheritable traits. Mutations are changes to those inheritable traits. When there are changes, NS starts to work on them, because the environment hasn't changed, but the traits of the individual have. Whether it is a positive or negative trait doesn't matter, NS will act upon it. It will also act when the environment changes, yet the traits remain the same.
ok, so there must be a lot of mutation occuring in order for there to be so much diveristy in life forms
Is this an accurate assumption?

This message is a reply to:
 Message 150 by Huntard, posted 11-27-2009 4:43 AM Huntard has replied

Replies to this message:
 Message 152 by Huntard, posted 11-27-2009 5:04 AM Peg has not replied

Huntard
Member (Idle past 2294 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 152 of 302 (537134)
11-27-2009 5:04 AM
Reply to: Message 151 by Peg
11-27-2009 4:54 AM


Re: Here's mine
Peg writes:
ok, so there must be a lot of mutation occuring in order for there to be so much diveristy in life forms
Is this an accurate assumption?
Well, I've heard Wounded King mention that each individual has about 100 mutations that their parents don't have. But you really should ask him about that, I don't really know.

I hunt for the truth
I am the one Orgasmatron, the outstretched grasping hand
My image is of agony, my servants rape the land
Obsequious and arrogant, clandestine and vain
Two thousand years of misery, of torture in my name
Hypocrisy made paramount, paranoia the law
My name is called religion, sadistic, sacred whore.
-Lyrics by Lemmy Kilmister of Motorhead

This message is a reply to:
 Message 151 by Peg, posted 11-27-2009 4:54 AM Peg has not replied

Replies to this message:
 Message 153 by DevilsAdvocate, posted 11-27-2009 6:20 AM Huntard has not replied

DevilsAdvocate
Member (Idle past 3101 days)
Posts: 1548
Joined: 06-05-2008


Message 153 of 302 (537139)
11-27-2009 6:20 AM
Reply to: Message 152 by Huntard
11-27-2009 5:04 AM


Re: Here's mine
Huntard writes:
Well, I've heard Wounded King mention that each individual has about 100 mutations that their parents don't have. But you really should ask him about that, I don't really know
I have read elsewhere that on average it is about 30 new mutations per individual (source: 30 New Mutations per Lifetime. However only DNA mutations in the gametes (egg and sperm), heriditary germline mutations, are inheritable which probably equals to less than 1 new mutation per individual that is inheritable, I am guessing. This is not counting the hundreds or thousands of previous heriditary germline mutations that are passed down from preceding generations.
Of course this average is not counting people under extreme circumstances i.e. those exposed to excess radiation, etc which tends to push these numbers of new inheritable mutations higher.
Just my thoughts. Wounded King, correct me if I am wrong in my assumptions here.
Edited by DevilsAdvocate, : No reason given.

One of the saddest lessons of history is this: If we've been bamboozled long enough, we tend to reject any evidence of the bamboozle. We're no longer interested in finding out the truth. The bamboozle has captured us. It is simply too painful to acknowledge -- even to ourselves -- that we've been so credulous. - Carl Sagan, The Fine Art of Baloney Detection
"You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep seated need to believe." - Carl Sagan
"It is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring." - Carl Sagan, The Demon-Haunted World

This message is a reply to:
 Message 152 by Huntard, posted 11-27-2009 5:04 AM Huntard has not replied

Replies to this message:
 Message 154 by Wounded King, posted 11-27-2009 7:09 AM DevilsAdvocate has replied

Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 154 of 302 (537143)
11-27-2009 7:09 AM
Reply to: Message 153 by DevilsAdvocate
11-27-2009 6:20 AM


Mutation rates
I have to say that 30 somatic mutations in a lifetime sounds implausibly low to me. I think historically such estimates have been based on techniques where phenotypic changes have been identified and used as a proxy for somatic mutation rather than actual measurements of change at the genetic level. These changes are often based on 1 or 2 marker proteins which may or may not be representative of mutation rate throughout the genome. One recent paper that looked at actual sequence level changes suggests that somatic mutation rates are actually 10-1000 times as high as traditional methods have estimated and their distibution is affected by factors such as the expression level of gene (Sylva et al., 2009).
However only DNA mutations in the gametes (egg and sperm), heriditary germline mutations, are inheritable which probably equals to less than 1 new mutation per individual that is inheritable, I am guessing.
I'm afraid your guesswork is wrong, probably due in part to the very low level of somatic mutation you are using as a base line. There is plenty of research suggesting that the total number of new mutations per diploid human genome per generation is ~100 (Kondrashov, 2002). These estimates are based both on cross species comparisons between humans and chimps and on the spontaneous rate of de novo mutations causing heritable Mendelian diseases.
TTFN,
WK

This message is a reply to:
 Message 153 by DevilsAdvocate, posted 11-27-2009 6:20 AM DevilsAdvocate has replied

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 Message 155 by DevilsAdvocate, posted 11-27-2009 7:22 AM Wounded King has not replied

DevilsAdvocate
Member (Idle past 3101 days)
Posts: 1548
Joined: 06-05-2008


Message 155 of 302 (537144)
11-27-2009 7:22 AM
Reply to: Message 154 by Wounded King
11-27-2009 7:09 AM


Re: Mutation rates
Awesome, thanks for the correction WK. I do learn alot from posting here as shown by these posts. Thanks for the links.

One of the saddest lessons of history is this: If we've been bamboozled long enough, we tend to reject any evidence of the bamboozle. We're no longer interested in finding out the truth. The bamboozle has captured us. It is simply too painful to acknowledge -- even to ourselves -- that we've been so credulous. - Carl Sagan, The Fine Art of Baloney Detection
"You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep seated need to believe." - Carl Sagan
"It is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring." - Carl Sagan, The Demon-Haunted World

This message is a reply to:
 Message 154 by Wounded King, posted 11-27-2009 7:09 AM Wounded King has not replied

Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 156 of 302 (537148)
11-27-2009 8:16 AM
Reply to: Message 136 by Granny Magda
11-26-2009 8:00 PM


Re: Back to Basics
You know, I really think you have a lot of nerve. First you have tried to say that I asked about natural selection, and NOT evolution. When I have pointed out to you that I VERY clearly asked about evolution-it is YOU who moves the goalposts by now saying that I never asked about RM! Then you dig even deeper to say that NO ONE has said I can't talk about RM, when there have been TEN people saying I shouldn't be allowed to talk about RM, and one even reported it to the moderator.
Meanwhile, very disingenuously many of you have tried to somehow separate the concept of Natural Selection from RM, exact for the fact that no one can show how you can have natural selection work in your evolution theory without them.
It must be very convenient for you evolutionists, you get to tell me what I can talk about, you get to tell me what I said, and you get to be moderated by another evolutionist who not only allows you all to inject numerous ad hominum attacks on everyone with a dissenting voice, but more importantly does nothing to stop all of you from derailing this thread (how many posts of there now been from people complaing that I am talking about RM when talking about evolution 50?-that's contributing to the topic???).
You can't talk about evolution without RM, your theory doesn't exist without them!!! If it does please explain it clearly how it can.
I guess under such terms, it is no surprise that you all are convinced your theory has nothing to explain-you silence anyone who challenges it!

This message is a reply to:
 Message 136 by Granny Magda, posted 11-26-2009 8:00 PM Granny Magda has replied

Replies to this message:
 Message 157 by Huntard, posted 11-27-2009 8:59 AM Bolder-dash has replied
 Message 159 by Granny Magda, posted 11-27-2009 9:09 AM Bolder-dash has not replied
 Message 160 by Tanndarr, posted 11-27-2009 9:12 AM Bolder-dash has not replied
 Message 163 by Admin, posted 11-27-2009 9:38 AM Bolder-dash has replied

Huntard
Member (Idle past 2294 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 157 of 302 (537151)
11-27-2009 8:59 AM
Reply to: Message 156 by Bolder-dash
11-27-2009 8:16 AM


Let's try one more time
Bolder-dash writes:
Meanwhile, very disingenuously many of you have tried to somehow separate the concept of Natural Selection from RM, exact for the fact that no one can show how you can have natural selection work in your evolution theory without them.
But nobody says evolution can work without RM. We say NS can work without RM, which is true.
It must be very convenient for you evolutionists, you get to tell me what I can talk about, you get to tell me what I said, and you get to be moderated by another evolutionist who not only allows you all to inject numerous ad hominum attacks on everyone with a dissenting voice, but more importantly does nothing to stop all of you from derailing this thread (how many posts of there now been from people complaing that I am talking about RM when talking about evolution 50?-that's contributing to the topic???).
That's because for some reason you don't seem to be able to grasp what we are saying. NS has nothing to do with RM, Evolution has to do with both of them.
You can't talk about evolution without RM, your theory doesn't exist without them!!!
And nobody is saying we should.
If it does please explain it clearly how it can.
It can't.
I guess under such terms, it is no surprise that you all are convinced your theory has nothing to explain-you silence anyone who challenges it!
Yeah, sure...It's not our problem you fail to grasp what we are trying to tell you.
So, one more time. When talking about evolution, you're including RM and NS, when talking about NS, RM becomes irrelevant. When talking about RM, NS becomes irrelevant.
Is it clear now? And don't go off about why everybody says you can't talk about evolution, you can, it's just so broad a topic that it will lead to a complete derailment of the thread. This is why we keep threads to more isolated topics here, and this is why everybody is telling you that you are off-topic, because you're original question was only about NS.
Now then. Is it clear? If not, please ask specific questions. Thanks.

I hunt for the truth
I am the one Orgasmatron, the outstretched grasping hand
My image is of agony, my servants rape the land
Obsequious and arrogant, clandestine and vain
Two thousand years of misery, of torture in my name
Hypocrisy made paramount, paranoia the law
My name is called religion, sadistic, sacred whore.
-Lyrics by Lemmy Kilmister of Motorhead

This message is a reply to:
 Message 156 by Bolder-dash, posted 11-27-2009 8:16 AM Bolder-dash has replied

Replies to this message:
 Message 161 by Bolder-dash, posted 11-27-2009 9:16 AM Huntard has replied

Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 158 of 302 (537153)
11-27-2009 9:09 AM


I believe I have reached the answer I was looking for very early on in the postings.
Your side has very little in the way of hard scientific evidence which can show that natural selection has been the cause of the diversity of life on earth. Instead what you have are some anecdotal studies of group of finches with varying beak sizes, guppies vacillating their amount of spots back and forth, drug resistance occurring in the poof of an eye, and a counting of fruit flies-all of which are subject to virtually any interpretation one wants to draw.
It seems the backbone of the theory is that no one has another explanation that is satisfying to your community, so it must be right. Its conjecture not science-most of which is being evangelized by individuals who have made it a point to boast of their atheist credentials, but yet and feel that this is irrelevant to their findings, yet would never allow the same liberty in opposition.
Perversely, your side has also attempted to validate your findings by dragging out theistic scientist who support your side-to somehow give credibility to your position-without ever questioning that their own beliefs could cloud their conclusions. Clouding of believes is a concept you only accept for the opposition.
Given the chance to prove your side scientifically (which is supposedly your strength) you have instead shown little science, and lots of diversion. The odd thing is that I am not even a creationist, and yet when you see what your side has to offer in the way of explanation and scientific reason-a mind that is capable of philosophic thought (not a particularly abundant trait in most evolutionists apparently-perhaps that's a mutation) one can't help but draw the conclusion that a lot of things in your theory are amiss.
Perhaps that is one conclusion one can draw from such a discussion-there may be some minds better suited to a scientific, molecular view of the world (but because of their detailed focus suffer from myopia-I see lots of evidence for that here), and others that are more capable of drawing conclusions from a much broader and expansive world view-and rarely the twain shall meet.
This is why the tired argument, "Sorry, you don't understand biology" makes me chuckle a bit. A theory of how things fit together is not the exclusive domain of biology- as you have all shown, there is little biology to support your argument anyway-what it requires is logic...so to that I would say, "Sorry, you simply can't understand logic, so you can probably never get it..but go read more books and maybe it will help."

Replies to this message:
 Message 164 by RAZD, posted 11-27-2009 11:37 AM Bolder-dash has not replied

Granny Magda
Member
Posts: 2462
From: UK
Joined: 11-12-2007
Member Rating: 4.0


Message 159 of 302 (537154)
11-27-2009 9:09 AM
Reply to: Message 156 by Bolder-dash
11-27-2009 8:16 AM


Re: Back to Basics
Hi BD,
You know, I really think you have a lot of nerve.
Why thank you very much, that's the most flattering thing I've heard all week.
First you have tried to say that I asked about natural selection, and NOT evolution.
That's because you did ask about NS, not evolution. If you disagree, perhaps you would like to point out exactly where you asked about evolution(as a whole that is).
Your OP is perfectly clear;
Bolder-dash writes:
Has natural selection really been tested and verified?
Your title asks if NS has been verified.
Bolder-dash writes:
I read recently where an editor of Discovery Magazine stated that Darwin provided a testable mechanism for evolutionary change, and as such it has stood up to the rigors of such testing.
You have heard that Darwin gave a mechanism for evolution and that it has been tested.
This is the only mention you make of evolution without further specifying natural selection.
Bolder-dash writes:
I am not so sure that this is true.
You have doubts that any such proof has been made.
Bolder-dash writes:
Can people point to tests that have verified that natural selection causes evolutionary change? What tests have they conducted? Do these tests accurately mimic the real world?
You ask for evidence that natural selection has verified.
Note that this appears to qualify your opening statement.
I would like to stipulate that talking about bacteria (in any form) does not qualify as any type of test, because ultimately we must be taking sexual reproduction, where choices are being made into account-so bacteria is out.
You don't want to talk about bacteria.
Bolder-dash writes:
Ok, so what are these tests which prove (or even provide solid evidence for) natural selection is the driver of evolutionary change?
You ask again for evidence that natural selection has been verified.
That is your entire OP. It makes no mention of mutation and the only actual questions you ask are specifically about NS.
When I have pointed out to you that I VERY clearly asked about evolution-it is YOU who moves the goalposts by now saying that I never asked about RM!
You very clearly asked nothing about evolution in general. The only questions you asked were about NS and its role in evolution. Naturally, everybody has assumed that you wanted to talk about NS.
Then you dig even deeper to say that NO ONE has said I can't talk about RM, when there have been TEN people saying I shouldn't be allowed to talk about RM, and one even reported it to the moderator.
*sigh* You are at perfect liberty to propose a new topic about random mutation. People are only reacting the way they are because you asked about NS and then threw a tantrum because nobody answered about RM. You are behaving like a child.
If you want to talk about the role of RM in evolution, you will find people happy to do so. What people are not happy to do is allow you to play bait and switch. If you want to talk about RM, propose a new topic.
Meanwhile, very disingenuously many of you have tried to somehow separate the concept of Natural Selection from RM, exact for the fact that no one can show how you can have natural selection work in your evolution theory without them.
Actually, it is trivially easy to demonstrate how NS could work without RM. Imagine that instead of mutation being random, it is guided. Each mutation is personally shaped by the guiding hand of whatever god you happen to favour. This direction is essentially undetectable, but it is enough to produce variation in inheritable characteristics. NS would then go on to act upon these variations, filtering out the harmful changes and leaving the useful ones.
It must be very convenient for you evolutionists, you get to tell me what I can talk about, you get to tell me what I said, and you get to be moderated by another evolutionist...
I'm not interested in your whining. If you think the game is fixed, don't play. Otherwise, man up and accept that NS and RM are separate processes.
Mutate and Survive

"A curious aspect of the theory of evolution is that everybody thinks he understands it." - Jacques Monod

This message is a reply to:
 Message 156 by Bolder-dash, posted 11-27-2009 8:16 AM Bolder-dash has not replied

Tanndarr
Member (Idle past 5182 days)
Posts: 68
Joined: 02-14-2008


Message 160 of 302 (537155)
11-27-2009 9:12 AM
Reply to: Message 156 by Bolder-dash
11-27-2009 8:16 AM


Re: Back to Basics
I see you're still putting up posts therefore you haven't been silenced. Playing the persecution card a little early in the game aren't we?
People are trying to point out that your take on evolution is not correct and are becoming frustrated at your inability to understand the point. So quit whining and support your arguments with evidence. Okay?
Now...briefly and in simple words:
Evolution is change in populations over time.
Mutation is one source of change.
Natural Selection filters changes by forcing all life to successfully reproduce in order to pass on the changes to following generations.
The Theory of Evolution explains how evolution happens by means of mutation and natural selection and (importantly) other means.
Don't reword any of that please. If you disagree with any of that then there's no point talking about any of the details until we can start talking the same language.
Oh yeah, if you need to change the scope of the thread you can ask the moderator to change the title. I doubt they'd do that in this case since it's gone on so long, but it could help avoid this in the future.

This message is a reply to:
 Message 156 by Bolder-dash, posted 11-27-2009 8:16 AM Bolder-dash has not replied

Bolder-dash
Member (Idle past 3629 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 161 of 302 (537156)
11-27-2009 9:16 AM
Reply to: Message 157 by Huntard
11-27-2009 8:59 AM


Re: Let's try one more time
Are you the moderator now too? Your side has many advantages I see.
How many contributions to the topic have you provided so far? How many tests to prove your side have you contributed?
Do you wish to calculate that as a percentage of the number of posts you have managed to bully into?

This message is a reply to:
 Message 157 by Huntard, posted 11-27-2009 8:59 AM Huntard has replied

Replies to this message:
 Message 162 by Huntard, posted 11-27-2009 9:22 AM Bolder-dash has not replied

Huntard
Member (Idle past 2294 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 162 of 302 (537157)
11-27-2009 9:22 AM
Reply to: Message 161 by Bolder-dash
11-27-2009 9:16 AM


Re: Let's try one more time
Bolder-dash writes:
Are you the moderator now too?
No. I have no moderator privileges here whatsoever, I simply tried to explain where the confusion is coming from, and to give you some tips on how to prevent it.
Your side has many advantages I see.
My side has reality to support it.
How many contributions to the topic have you provided so far?
You can see that at the top of the page, my number of posts in this thread are listed there.
How many tests to prove your side have you contributed?
None. I first tried to get the confusion to go away.
Do you wish to calculate that as a percentage of the number of posts you have managed to bully into?
Bully into? None. I simply give you my oppinion and view of things, feel free to ignore them.

I hunt for the truth
I am the one Orgasmatron, the outstretched grasping hand
My image is of agony, my servants rape the land
Obsequious and arrogant, clandestine and vain
Two thousand years of misery, of torture in my name
Hypocrisy made paramount, paranoia the law
My name is called religion, sadistic, sacred whore.
-Lyrics by Lemmy Kilmister of Motorhead

This message is a reply to:
 Message 161 by Bolder-dash, posted 11-27-2009 9:16 AM Bolder-dash has not replied

Admin
Director
Posts: 12995
From: EvC Forum
Joined: 06-14-2002
Member Rating: 2.3


Message 163 of 302 (537158)
11-27-2009 9:38 AM
Reply to: Message 156 by Bolder-dash
11-27-2009 8:16 AM


Re: Back to Basics
Hi Bolder-dash,
I appreciate some of the difficulties you're facing. I agree that the evolutionists, who I believe are well intentioned individually, are collectively providing a confusing picture, but on the other hand I can see where correct information is being provided that you're missing. For example, you say:
Bolder-dash writes:
You can't talk about evolution without RM, your theory doesn't exist without them!!! If it does please explain it clearly how it can.
I'm sure everyone agrees with you. You can't talk about evolution without mentioning random mutations. But you *can* talk about natural selection without mentioning mutations, and several people have attempted to explain this.
...and you get to be moderated by another evolutionist...
Don't think of me as an evolutionist moderator, but instead as a moderator who understands evolution. As moderator I'm not agreeing with the evolutionists that evolution is right and creation is wrong. I'm agreeing with them that they are correctly defining evolution, natural selection, random mutation, etc.
Whenever you receive more than one definition of something, as is happening here for the fundamental terminology of evolution, you'll always be able to find differences and apparent conflicts in those definitions. No two people will ever define the same thing the same way. This is just a fact of life. You're going to have to work through the different and differing explanations in order to build your own understanding of evolution. You might find other online resources helpful. For example, Wikipedia provides this definition of natural selection:
Wikipedia writes:
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 is a key mechanism of evolution.
Notice, no mention of mutations. The first mention of mutation occurs a few paragraphs further on and says this, which includes an important point you've been making yourself where it comments about the need for understanding the origin of variation:
Wikipedia writes:
Although a complete theory of evolution also requires an account of how genetic variation arises in the first place (such as by mutation and sexual reproduction) and includes other evolutionary mechanisms (such as gene flow), natural selection is still understood as a fundamental mechanism for evolution.
I don't know if you appreciate sports analogies, but I always feel that the best referees are those you're not aware of. I feel the same way about moderation. Moderators should facilitate discussions, not intrude or impose upon them. A light hand is best, allowing thread participants to work out as many difficulties as they can on their own.

--Percy
EvC Forum Director

This message is a reply to:
 Message 156 by Bolder-dash, posted 11-27-2009 8:16 AM Bolder-dash has replied

Replies to this message:
 Message 170 by Bolder-dash, posted 11-27-2009 9:57 PM Admin has replied

RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 164 of 302 (537181)
11-27-2009 11:37 AM
Reply to: Message 158 by Bolder-dash
11-27-2009 9:09 AM


Revised topic: Has speciation been tested and verified.
Hi Bolder-dash,
Your side has very little in the way of hard scientific evidence which can show that natural selection has been the cause of the diversity of life on earth.
Little has been presented, because your initial posts were so confused, we thought you were talking about only tests of natural selection.
Now, if you want to talk about how diversity occurs via evolution, for example, that is an entirely different concept, and one not limited to natural selection.
What you want to talk about is speciation: speciation is where diversity begins, as during speciation events a parent population divides into two daughter populations that become reproductively isolated, stop sharing genetic material, and then evolve along different paths due to different ecologies and selection pressure. The daughter populations become increasingly diverse from each other after the speciation event, for the simple reason that there is no process to make them to be similar.
Natural selection is one of the processes that causes this, mutations are also a necessary part of speciation, but these are not the only mechanisms involved.
Speciation - Wikipedia
quote:
Speciation is the evolutionary process by which new biological species arise. The biologist Orator F. Cook seems to have been the first to coin the term 'speciation' for the splitting of lineages or 'cladogenesis,' as opposed to 'anagenesis' or 'phyletic evolution' occurring within lineages.[1][2] Whether genetic drift is a minor or major contributor to speciation is the subject of much ongoing discussion. There are four geographic modes of speciation in nature, based on the extent to which speciating populations are geographically isolated from one another: allopatric, peripatric, parapatric, and sympatric. Speciation may also be induced artificially, through animal husbandry or laboratory experiments. Observed examples of each kind of speciation are provided throughout.[3]
Please note that last part: observed examples of each kind of speciation are provide. In other words, speciation has been tested and verified (as has natural selection, as has mutations, as has genetic drift, as have all the other mechanisms of evolution that go into the overall process).
As noted on Definition of Evolution Message 212, a definition of evolution is provided that I have referred you to several times, but you seem to have ignored. Here is is in full:
quote:
In The defintion of the theory of evolution (proposed new topic) Bolder-dash writes:
Since there have been a number of posters claiming that 'natural selection" has no specific meaning other than one stronger organism surviving while another weaker one perishes (in any means under any circumstances, a bomb, genocide, whatever), I think this now calls into question exactly what the definition of the ToE says.
Can we please have a complete definition of what is the Theory of Evolution?
He also feels that discussing this in the current Has natural selection really been tested and verified? thread will be off-topic. I concur.
I suggest we first define what is meant by evolution as a biological process, and then discuss what is meant by the theory of evolution.
As a biological process, evolution is a change in the frequency distribution of hereditary traits in breeding populations from generation to generation. This change occurs as a result of a number of other contributory biological processes, including
  • natural selection, by survival of individual organisms with hereditary traits that improve their relative ability to survive,
  • natural selection, by reproduction of individual organisms with hereditary traits that improve their relative ability to reproduce,
  • mutations, that cause random changes to hereditary traits, some beneficial, some deleterious, and some neutral when viewed in context of selection of organisms that have the new mutations,
  • neutral drift, or neutral selection, where the variations that are neutral to selection pressures change over time, thus altering the total make-up of hereditary traits within the breeding populations but not resulting from selection,
  • stochastic processes, random disasters wiping out sectors of a breeding population, and in the process altering the total make-up of hereditary traits within the breeding populations but not resulting from selection,
  • developmental processes, changes in the development of organisms from conception to reproductive ability that are due to environmental factors,
  • population dynamics, the limited ability of large populations to share new hereditary traits through normal reproduction over time,
  • population dynamics, the limited ability of large populations when they are divided into sub-populations, especially when these sub-populations are living in different ecologies with different selection pressures,
  • behavior patterns that can affect survival and breeding that are passed from generation to generation by learning (memes),
  • isolation mechanisms, mechanisms that tend to isolate sub-populations from breeding, either geographical, temporal or behavioral,
  • reproductive isolation, resulting in daughter populations that no longer share new hereditary traits, and thus are free to diverge into new, albeit related, species,
  • common ancestry, results from speciation events, where daughter populations continue to diverge by the processes of evolution in independent ways due to different ecological pressures, and results in the formation of a tree of life, or cladistic relationships, depending on the time scale of observation,
  • etc
It needs to be noted that each one of these contributory biological processes has been observed and validated to occur in nature as well as in the lab: these biological processes are facts, not theory. Each of these processes can contribute in different degrees to the evolution of a species at different times, and there is no set mixture of these processes for the overall process of evolution to occur, as long as the end result is a change in the frequency distribution of hereditary traits in breeding populations from generation to generation. Thus too, the biological process of evolution has been observed, and is a known fact. Speciation has been observed as well, and is a known fact of biological evolution - the science of studying evolutionary processes in biological systems.
It also needs to be noted that there are random factors introducing changes to the distribution of hereditary traits, and there are response factors, where the result is a response to external ecological constraints on the populations.
Darwin's insight was that natural processes could accomplish the same kind of selection as was observed in the artificial selection of animal breeding programs (dogs, cows, etc), and that this selection process could account for the diversity of life as we know it, from the world around us, from history, from the natural history of the planet, and the fossil record. Since Darwin's time some of his original concepts (such as how variation was acquired), have been discarded in favor of new information not available then (such as genetics), but the overall concept that all of the diversity of life could be explained by the process of evolution has remained.
This is the root of the theory, the facts of the known biological processes form the foundation, and the overall process of evolution is hypothesized to apply to all changes in the past: The theory of evolution (ToE), simply stated, is that the diversity of life as we know it today -- from history, from prehistory, from paleontology, from the natural history of the planet, from the fossil record, and finally from the genetic record of life -- can all be explained by the biological process of evolution, a change in the frequency distribution of hereditary traits in breeding populations from generation to generation.
Evolution - the process - is an observed process and is a fact, including but not limited to speciation events that cause division of breeding populations into distinct sub-populations that can evolve independently.
Evolution - the science - is the study of the biological processes that lead to evolution in breeding populations and to speciation and the development of long term trends in diversity due to common ancestry, and the formation of various cladistic branches and their inter-relationships as a result of continued evolution after speciation.
Evolution - the theory - is the hypothesis that the process of evolution - change in the frequency distribution of hereditary traits in breeding populations from generation to generation - is sufficient to explain the diversity of life as we know it.
It should also be noted, that framed this way, the Theory of Evolution is a very robust theory, not just because it has been validated by thousands of concurring observations and an absolute absence of contradictory evidence (not one change has been observed that is not due to a known biological process), but because falsification of one part of the processes contributory to the overall process does not invalidate the overall theory. The theory, however is falsifiable -- just demonstrate that a specific observed change cannot possibly be caused by these biological processes.
Enjoy.
References:
(1) Berkeley University website on evolution,
(2) University of Michigan website on evolution and natural selection and speciation
Note that there are 12 processes listed, two involving natural selection (one for survival and one for reproduction), and one for random mutations, and that the list is incomplete.
Evolution is the change in the frequency distribution of heritable traits in breeding populations from generation to generation. It does not matter which individual process or what combination of these processes is involved in any specific instance, as long as the change occurs, it IS evolution.
Evolution is constantly ongoing, and there is no known species where evolution is not occurring.
I gave you the example of Pelycodus (Message 126) as a record of speciation in the fossil record, and showed how both natural selection and mutation assisted that process, as indeed they are normally present in most speciation events. The simple fact is that during the speciation process daughter populations are being selected for different ecologies, and over time the differences in mutations available (new and old), and in the selection pressures from the different ecologies, necessarily result in different end species.
This is the source of diversity. Without speciation all life would be one species.
Enjoy.
Edited by RAZD, : some content hidden per moderator request

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This message is a reply to:
 Message 158 by Bolder-dash, posted 11-27-2009 9:09 AM Bolder-dash has not replied

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 Message 166 by Admin, posted 11-27-2009 2:23 PM RAZD has seen this message but not replied

Parasomnium
Member
Posts: 2224
Joined: 07-15-2003


Message 165 of 302 (537185)
11-27-2009 12:37 PM
Reply to: Message 139 by Peg
11-27-2009 12:16 AM


Re: Why?
Peg writes:
ok, so If i have a baby which survives, thats natural selection taking place???
Your having a baby? Yes, that's natural selection taking place. It means your particular traits have kept you alive long enough in the struggle for existence (food, shelter, a mate) to produce a child and pass on the genes responsible for those traits.
That your baby survives? Is that natural selection taking place? Well, that depends on how long your baby survives. Once you are a grandmother the answer is 'yes'. Until then it's 'no'.

"Ignorance more frequently begets confidence than does knowledge: it is those who know little, not those who know much, who so positively assert that this or that problem will never be solved by science." - Charles Darwin.

This message is a reply to:
 Message 139 by Peg, posted 11-27-2009 12:16 AM Peg has not replied

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