Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
0 online now:
Newest Member: popoi
Post Volume: Total: 915,817 Year: 3,074/9,624 Month: 919/1,588 Week: 102/223 Day: 0/13 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Has natural selection really been tested and verified?
lyx2no
Member (Idle past 4716 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 211 of 302 (537350)
11-28-2009 8:29 AM
Reply to: Message 206 by Bolder-dash
11-28-2009 7:49 AM


Sand?
with their heads in the sand.
Sand? Show me where anyone suggested sand.

It's not the man that knows the most that has the most to say.
Anon

This message is a reply to:
 Message 206 by Bolder-dash, posted 11-28-2009 7:49 AM Bolder-dash has not replied

cavediver
Member (Idle past 3643 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 212 of 302 (537351)
11-28-2009 8:32 AM
Reply to: Message 206 by Bolder-dash
11-28-2009 7:49 AM


Re: Back to Basics
the intellectual community that also happens to see there are gaping holes in this theory
Excellent, a new definition of the empty set {}

This message is a reply to:
 Message 206 by Bolder-dash, posted 11-28-2009 7:49 AM Bolder-dash has replied

Replies to this message:
 Message 221 by Bolder-dash, posted 11-28-2009 9:52 AM cavediver has replied

Peg
Member (Idle past 4930 days)
Posts: 2703
From: melbourne, australia
Joined: 11-22-2008


Message 213 of 302 (537354)
11-28-2009 8:37 AM
Reply to: Message 210 by cavediver
11-28-2009 8:29 AM


Re: Back to Basics
cavediver writes:
Ah, you obviously haven't seen the odds we've given you in the book we're running Tho' to be fair, slevesque is favourite at the moment. Care to place a wager?
a wager on what? on me turning to the dark side???

This message is a reply to:
 Message 210 by cavediver, posted 11-28-2009 8:29 AM cavediver has not replied

Dr Adequate
Member (Idle past 285 days)
Posts: 16113
Joined: 07-20-2006


(2)
Message 214 of 302 (537358)
11-28-2009 8:44 AM
Reply to: Message 196 by Peg
11-28-2009 6:40 AM


Back to Basics --- Vocabulary For Peg
Let's take it from the top.
(1) Evolution is a heritable change in the composition of a gene pool.
This would include a lot of things. The changes in the beaks of the finches is evolution. The descent of humans from what we may as well call "monkeys" would be evolution. If every lioness in the world stopped giving birth to lion cubs and started giving birth to unicorns, and this involved a change from lion DNA to unicorn DNA (and how could it not?) then this would also be evolution. Indeed, if all lions suddenly turned into unicorns, by magic or the will of God, and this change was inherited by their offspring, then this too would be evolution.
(2a) The principle of common descent is the proposition that all present species have been produced from just one original life-form by evolution.
(2b) A claim of common ancestry concerning any bunch of species is the claim that they all evolved from the same species. So common descent is the claim that all species have common ancestry.
(3) The theory of evolution is a theory about how evolution happens. It proposes that it occurs as a result of such well-known genetic processes as reproduction, mutation, recombination, lateral gene transfer, natural selection (including sexual selection), artificial selection, genetic drift, and the laws of probability.
Note that this theory is a constraint on evolution (just as every other scientific theory is a constraint on its subject matter). It says what can't happen --- for example, it rules out lions giving birth to unicorns.
The principle of common descent is almost always taken to be the initial condition for the theory of evolution, so much so that people often speak of it as part of that theory. I've done that myself, I admit. But to be accurate we should separate them, just as the proposition that the Universe began with a Big Bang is separate from Einstein's theory of General Relativity.
(4) The law of natural selection is the proposition that those organisms which are genetically best suited to propagate their genes will indeed tend to get their genes propagated better than those organisms that are less well-suited to that task.
---
Now, let's look at what creationists should be saying.
You shouldn't say: "I don't believe in evolution", 'cos it happens.
You shouldn't say: "I don't believe in the theory of evolution" unless that's absolutely what you mean. Because a lot of creationists do believe in it, and believe that they can use it to disprove common descent. My favorite creationist slevesque is going down that route. Remember that, as I said, the theory of evolution places constraints on what evolution can do. If anyone wants to prove that common descent couldn't possibly happen, then the theory of evolution is the only tool they've got to work with.
You shouldn't say: "I don't believe in natural selection", because the law of natural selection is so obvious that you could prove it from your armchair without even glancing at nature.
What you should be saying is: "Yes, evolution happens, we observe it. And I grant you, indeed I insist, that there are no known mechanisms for evolution except those enumerated in the theory of evolution. And in particular the law of natural selection is so obvious that no sane person could dispute it. What I dispute is the common ancestry of men and monkeys and indeed the whole principle of common descent".
And if you were someone who argues after the style of slevesque, you should then add: "As a matter of fact, I think that the theory of evolution puts the tin lid on the whole notion of common descent".
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 196 by Peg, posted 11-28-2009 6:40 AM Peg has replied

Replies to this message:
 Message 219 by Peg, posted 11-28-2009 9:12 AM Dr Adequate has replied

ICANT
Member
Posts: 6769
From: SSC
Joined: 03-12-2007
Member Rating: 1.5


Message 215 of 302 (537359)
11-28-2009 8:48 AM
Reply to: Message 205 by Dr Adequate
11-28-2009 7:28 AM


Re: Back to Basics
Hi Dr,
Dr Adequate writes:
A population with an average small beak size evolved into a population with an average large beak size.
But that is not what the study shows.
It simply shows in wet times the species that has the small beaks have a better survival rate than those with large beaks.
It also shows that the species that has the large beaks survive better in the dry times than those with the small beaks.
It does not show the species with the small beaks growing large beaks, and the species with the large beaks growing small beaks.
Now when I can take a 100 lb. piney woods hog and breed her with a Duroc breed that averages 400 lb. and get an offspring that averages 200 lb. then breed that offspring to a breed that averages 800 lbs. and get a breed that averages 600 lbs that can survive off less water and food for extended periods of time I call that forced evolution. I did this back in the 50's.
That was un natural selection as I was doing the selecting.
Now back to the finches. They have been doing this survival of the species that gets the most food for millions of years. Nothing changes the one that gets the most food survives better.
Now if those finches could really adapt they would evolve a small beak that could crush the hard seed as easily as the large beaks.
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 205 by Dr Adequate, posted 11-28-2009 7:28 AM Dr Adequate has replied

Replies to this message:
 Message 218 by Dr Adequate, posted 11-28-2009 8:55 AM ICANT has not replied

Admin
Director
Posts: 12998
From: EvC Forum
Joined: 06-14-2002
Member Rating: 2.3


Message 216 of 302 (537361)
11-28-2009 8:52 AM
Reply to: Message 203 by Bolder-dash
11-28-2009 7:10 AM


Re: Back to Basics
Hi Bolder-dash,
I think you're misinterpreting what is being said, both by myself and others. When I said, "that natural selection would go on even if for some mysterious reason random mutations ceased occurring," that didn't mean I was asking you to talk about natural selection independent of evolution. What that meant was that even if all random mutations ceased occurring, evolutionary change over time would still occur through natural selection.
I also said, "You're quite free to discuss random mutations as it relates to natural selection."
I think this is enough moderator interaction. In this thread please start discussing and stop complaining. Your perceived mistreatment is not the topic of this thread. If you're having problems with discussion then please take the issues to Report discussion problems here: No.2.
Please, no replies to this message.
Edited by Admin, : Fix thread link.

--Percy
EvC Forum Director

This message is a reply to:
 Message 203 by Bolder-dash, posted 11-28-2009 7:10 AM Bolder-dash has not replied

Dr Adequate
Member (Idle past 285 days)
Posts: 16113
Joined: 07-20-2006


Message 217 of 302 (537362)
11-28-2009 8:54 AM
Reply to: Message 207 by Peg
11-28-2009 8:01 AM


Re: Back to Basics
right
so no new species evolved...they were still finches.
Right.
No-one has ever claimed otherwise.
We claim that this is an example of natural selection in action.
this is just moving the goalposts. What really was happening to the finches is that they were adapting to change. Like animals who loose their winter coat in summer.
No, not like that.
This is not a change that happened to any finch as an individual. No particular finch lengthened its beak. What happened was that the finches with longer beaks had more offspring.
This seems to be where you're getting confused. What happened was not like a cat shedding its fur in summer, or like me getting a tan when I moved to a sunnier climate. No individual finch changed. The reproductive success rates of the finches changed, so the proportion of the genes in the gene pool changed.
That's what makes it evolution.
I take it that this is how the ToE has changed greatly over the years.
You've separated 'descent from a common ancestor' and the 'ToE' as if they are two different things.
in a few words, please explain the difference between:
'common descent'
'the theory of evolution'
Anticipating your need, I did that in my previous post.

This message is a reply to:
 Message 207 by Peg, posted 11-28-2009 8:01 AM Peg has not replied

Dr Adequate
Member (Idle past 285 days)
Posts: 16113
Joined: 07-20-2006


Message 218 of 302 (537364)
11-28-2009 8:55 AM
Reply to: Message 215 by ICANT
11-28-2009 8:48 AM


Re: Back to Basics
But that is not what the study shows.
It simply shows in wet times the species that has the small beaks have a better survival rate than those with large beaks.
It also shows that the species that has the large beaks survive better in the dry times than those with the small beaks.
It does not show the species with the small beaks growing large beaks, and the species with the large beaks growing small beaks.
* sigh *
We're not talking about two different species.

This message is a reply to:
 Message 215 by ICANT, posted 11-28-2009 8:48 AM ICANT has not replied

Replies to this message:
 Message 228 by herebedragons, posted 11-28-2009 10:28 AM Dr Adequate has replied

Peg
Member (Idle past 4930 days)
Posts: 2703
From: melbourne, australia
Joined: 11-22-2008


(1)
Message 219 of 302 (537368)
11-28-2009 9:12 AM
Reply to: Message 214 by Dr Adequate
11-28-2009 8:44 AM


Re: Back to Basics --- Vocabulary For Peg
DrAdequate writes:
(1) Evolution is a heritable change in the composition of a gene pool.
Ok, so right here is where we see that the original theory of evolution - Descent with modification leading to all the millions of forms of life - has changed to
inheritable change in the gene pool
Of course im not opposed to this idea. I've had 3 children and they all appear slightly different....isnt that inheritable change in the gene pool. Their genes will be very close to mine, but not quite because my reproduction has created something different to me...the same, but different.
DrAdequate writes:
The theory of evolution is a theory about how evolution happens.
Ahhh that is a revelation. Never heard it put that way before.
DrAdequate writes:
What you should be saying is: "Yes, evolution happens, we observe it. And I grant you, indeed I insist, that there are no known mechanisms for evolution except those enumerated in the theory of evolution. And in particular the law of natural selection is so obvious that no sane person could dispute it.
What I dispute is the common ancestry of men and monkeys and indeed the whole principle of common descent".
i see the difference now and appreciate that you went all lay person onme.
It is definately the common descent thing that creationists are opposed to. I dont have a problem with the 'changes in gene pool' because we can see that clearly and it works.
But in this area of linking all life forms with a long line of descent, we just cant see it...the fossil record doesnt show it, it shows fully formed life springing out in abundance at the same time.
So yes, i think i get it...damn, i'll have nothing to debate over!
Edited by Peg, : No reason given.

This message is a reply to:
 Message 214 by Dr Adequate, posted 11-28-2009 8:44 AM Dr Adequate has replied

Replies to this message:
 Message 225 by Dr Adequate, posted 11-28-2009 10:16 AM Peg has not replied

Bolder-dash
Member (Idle past 3630 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 220 of 302 (537374)
11-28-2009 9:36 AM


hmm...very interesting point..if all RM somehow ceased, evolutionary change over time would still continue to happen through natural selection. I wonder what it would be occurring on, the previous RM perhaps??
So, if that's the case, if RM never happened at all, evolution would still continue to occur through NS I guess. I mean the moderator said so, so it must be true. So, RM are in fact not necessary elements of evolution after all. And that makes parasomnium and huntard wrong then because they claim it is an essential element? Or is that only in the real world, not on the evolutionists web page world?

Replies to this message:
 Message 237 by NosyNed, posted 11-28-2009 11:15 AM Bolder-dash has not replied

Bolder-dash
Member (Idle past 3630 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 221 of 302 (537385)
11-28-2009 9:52 AM
Reply to: Message 212 by cavediver
11-28-2009 8:32 AM


Re: Back to Basics
Cavediver,
I believe you are a smart man in real life, probably liberal in your politics, probably socially conscious, probably even decent.
Therefore it comes as a bit of a surprise to me that you would really believe that one can not be an intelligent thinker, and see there are some problems with your theory. You immediately dismiss such a large group of people, simply because they find some of the stretches of logic to be too elastic, be it in the denial of the uniformity of the universe, or the proposition that something can't come from nothing, or any other hundreds of reasons why. Your glib response which you probably meant as a joke (which you won't be admonished for being off topic on)is surprising, but also indicative of the reality of the community here. You all can't possibly believe that someone smart can possibly disagree with you, so you all are anchored into your positions, void of any need for mental consideration, in exactly the same way that you claim creationists are. That doesn't leave much room for anything constructive to be achieved on this forum at all.
I certainly have lost interest.

This message is a reply to:
 Message 212 by cavediver, posted 11-28-2009 8:32 AM cavediver has replied

Replies to this message:
 Message 226 by cavediver, posted 11-28-2009 10:18 AM Bolder-dash has replied

Dr Adequate
Member (Idle past 285 days)
Posts: 16113
Joined: 07-20-2006


Message 222 of 302 (537386)
11-28-2009 10:01 AM
Reply to: Message 206 by Bolder-dash
11-28-2009 7:49 AM


Re: Back to Basics
You know Peg, one of the reasons why evolutionist have been able to stifle the conversation, and argument in their favor regarding schools and other avenues for learning more about our existence, is by doing exactly what they do on this site. They attempt to belittle and characterize anyone who disagrees with their position as being whacky, uneducated, brain-washed religious zealots, or people with their heads in the sand. They do it here on this forum (which in actuality is a evolutionist website-which allows creationists to participate, and they do it regularly to you.
Anytime they are challenged to defend anything, they throw out the same card time and time again, their ace in the hole-"Oh, you just don't understand science."
But has it not occurred to you that in your case this is true?
That you do not, in fact, know evolutionary biology from a hole in the ground?
You may have heard the expression: "Don't bring a knife to a gunfight".
Well, to continue that metaphor, you have brought a turnip to a gunfight. You have pointed it at your opponent, you have shouted "BANG" very loudly, and now you are throwing a hissy-fit because instead of him politely lying down and saying "OK, you shot me, I admit that I'm dead", he's standing there laughing at you for bringing a turnip to a gunfight.

This message is a reply to:
 Message 206 by Bolder-dash, posted 11-28-2009 7:49 AM Bolder-dash has not replied

Bolder-dash
Member (Idle past 3630 days)
Posts: 983
From: China
Joined: 11-14-2009


Message 223 of 302 (537388)
11-28-2009 10:12 AM
Reply to: Message 209 by Peg
11-28-2009 8:25 AM


Re: Back to Basics
Exactly how many posts in this thread can you read that refer to the topic?
After you can answer that question, then perhaps you can tell me how worthwhile the forum is, and explain to me how its a debate, as opposed to a trial where the plaintive is also the judge, the jury , and the bailiff. Enjoy your flagellation. I think I will stick to sites that actually have a real moderator for now.
Or even no moderator would be an improvement.

This message is a reply to:
 Message 209 by Peg, posted 11-28-2009 8:25 AM Peg has not replied

Replies to this message:
 Message 227 by Dr Adequate, posted 11-28-2009 10:20 AM Bolder-dash has replied

herebedragons
Member (Idle past 858 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


Message 224 of 302 (537389)
11-28-2009 10:14 AM
Reply to: Message 177 by Peg
11-28-2009 12:30 AM


Re: Speciation
thats what im intersted in...biological barriers
Peg - I too am interested in these "biological" barriers. I have been told that no such barriers exist, as NS is opportunistic - it works with the materials it has and keeps "evolving".
and the reason is because if it occurs among other species and if its a part of evolution, then it would surely happen among humans too
obviously, just because it hasn't happened doesn't mean it can't. But I do wonder why it hasn't happened and why the criteria for speciation is not consistantly applied.
Razd writes:
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.
I also understand that there does not need to be genetic or biological isolation for speciation to occur, only reproductive isolation.
Again Razd wrote:
Again, the critical element is whether the populations are reproductively isolated. This isolation can occur pre-mating based on changes to mating behavior.
There have been several examples of human populations being reproductively isolated.
1. Maya Indians - South America from about 2000BC to 900AD.
2. Current populations of indiginous peoples in both South America and Africa who do not breed either by ethnic choices or geographical isolation.
3. Native American Indians - Supposed to have immigrated to North America at least 12,000 years ago and possibly as far back as 50,000 years. Plenty of time to speciate, don't you think?
4. I understand the Ancient Egyptians were isolated for thousands of years (primarily by choice), but I don't have details or references right now.
Just these four examples provide plenty of opportunity for human evolution, or more precisely speciation, but has not been shown to have happened. Each of these examples faced vastly different environmental pressures and ecologies. One may argue that evolution has occured, as we have varing skin colors, average heights, limb lengths, facial structures, ect. But none have been classified as a new species. These variations would be enough to classify a new species in Greenish warblers, Galapogos finches, Peppered moths and others. I wonder if it is actually a stretch to consider these specimens have truly "speciated".
I have no problem accepting that 'evolution' has indeed occurred in all the above examples, but I question the extent of it. And I question the accuracy of taking the above examples and extrapolating them into the following statement:
Razd:
By this means, an arm can develop into a wing, or a skin flap can develop into a gliding surface.
I am still convinced there are "biological barriers" (I am using that term because I don't know how else to refer to it) to evolution. What is the evidence to the contrary? Honestly I still have more studing to do on the Greenish warbler and the Galapogos finches, but as far as I could tell, reproductive isolation is established by social and morphological reason only, not biological.
Thoughts any one??

This message is a reply to:
 Message 177 by Peg, posted 11-28-2009 12:30 AM Peg has replied

Replies to this message:
 Message 248 by Peg, posted 11-28-2009 6:16 PM herebedragons has replied

Dr Adequate
Member (Idle past 285 days)
Posts: 16113
Joined: 07-20-2006


Message 225 of 302 (537391)
11-28-2009 10:16 AM
Reply to: Message 219 by Peg
11-28-2009 9:12 AM


Re: Back to Basics --- Vocabulary For Peg
Ok, so right here is where we see that the original theory of evolution - Descent with modification leading to all the millions of forms of life - has changed to
inheritable change in the gene pool ...
No, you're wrong.
Read the definitions again.
You are still confusing evolution with the theory of evolution, and the theory of evolution with common descent. The last confusion is forgivable, the first is not.

This message is a reply to:
 Message 219 by Peg, posted 11-28-2009 9:12 AM Peg has not replied

Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024