Both Jbuza and Thinker have some merit in the above posts. It is absolutely correct to say that the the theory of evolution will NEVER be proven true, just as it can be said creationism will never be proven true. That is because they are theories...in a similar sense. gravity will never be proven as a reason things fall because it is also a theory. We must simply provide support for whatever stand we take. There is no way to say that the theory of evolution might be wrong, just as there is no way to say creationism might be wrong. However, in science we are taught to work with the best possible model or the most viable and testable explanation for observations. That is why evolution is so successful, and that is why intelligent design and creationism have failed as valid scientific alternatives to ToE. Take your coelocanth example...if someone just wanted to say that this fish is the way it is because it was designed that way, how do you test that hypothesis? Haven't you effectively shut the door on scientific investigation by saying "it is because it is"; however, the theory of evolution provides a method for testing its own validity by providing questions such as "What are its ancestors like, how would this body form be more successful than another in its habitat, etc" which can then be investigated. Evolution is the best testable hypothesis we have for the way things are, and I don't mean that in a best of the worst scenario such as is commonly used for politicians. Much of evolutionary theory is used in a predictive fashion to describe how things should be before they are examined, rather than as an "after the fact" explanation as you imply. Even when used in a predictive fashion ToE how been correct more times than I care to believe is due to chance. If a testable alternative to ToE emerged from out of the darkness, I'm sure it would start appearing throughout the scientific literature. However, as of now evolution is the best testable hyothesis.Jbuza wrote:Nope. I'm saying at some point perhaps it would be the better part of science to say perhaps the theory is wrong, instead of just coming up with an explanation for every problem that arises with the theory.
Coelacanth: Fish defying the ages, a challenge to evolution
-
- Established Member
- Posts: 116
- Joined: Thu Nov 17, 2005 9:40 am
- Christian: No
- Location: Carbondale, IL
- August
- Old School
- Posts: 2402
- Joined: Wed Dec 29, 2004 7:22 pm
- Christian: Yes
- Sex: Male
- Creation Position: Day-Age
- Location: Texas
- Contact:
Hi thereal,
I hear the argument about testability a lot, and how evolution is considered testable. Out of curiosity, can you maybe explain how natural selection and fossil lineages are testable?
Also, can you maybe expand a bit on what you think it would take for ID to be a testable hypothesis?
Thanks
I hear the argument about testability a lot, and how evolution is considered testable. Out of curiosity, can you maybe explain how natural selection and fossil lineages are testable?
Also, can you maybe expand a bit on what you think it would take for ID to be a testable hypothesis?
Thanks
Acts 17:24-25 (NIV)
"The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. [25] And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else."
//www.omnipotentgrace.org
//christianskepticism.blogspot.com
"The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. [25] And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else."
//www.omnipotentgrace.org
//christianskepticism.blogspot.com
- BGoodForGoodSake
- Ultimate Member
- Posts: 2127
- Joined: Mon Aug 29, 2005 9:44 am
- Christian: No
- Location: Washington D.C.
The analysis is done on living species and the fossil evidence is an auxiliary peice of evidence.August wrote:Hi thereal,
I hear the argument about testability a lot, and how evolution is considered testable. Out of curiosity, can you maybe explain how natural selection and fossil lineages are testable?
Also, can you maybe expand a bit on what you think it would take for ID to be a testable hypothesis?
Thanks
Fossil evidence is not testable due to the fact that it can be incomplete. Also fossils usually do not preserve soft tissue, which makes it difficult to determine if the fossils belong to different species.
Fossil lineages are likewise disputable because of the above mentioned facts. It is because of analysis of living species today that we are able to speculate on fossil lineages.
Natural selection is a conclusion reached on the following observations.
All life produces far more offspring than the environment can support.
All living things pass on their traits to their offspring.
Not all offspring will survive and whatever allows certain individuals to procreate while others do not is termed natural selection.
If anyone has an alternative conclusion to some individuals surviving while others do not, I am open to sugestions.
It's akin to a group of students. There is limit to approved applications to top Universities. Some of those students will not get into the a top university. There must be something determining who goes and who does not. Of course in the chaotic natural world this process is more haphazard and less clear.
The preponderance of evidence and testable hypothesys' lies with living organisms.
It is not length of life, but depth of life. -- Ralph Waldo Emerson
- August
- Old School
- Posts: 2402
- Joined: Wed Dec 29, 2004 7:22 pm
- Christian: Yes
- Sex: Male
- Creation Position: Day-Age
- Location: Texas
- Contact:
Hi Bgood, thanks for the response. So we agree that the fossil lineage evidence is not testable, and therefore cannot be submitted as proof for evolution.BGoodForGoodSake wrote: The analysis is done on living species and the fossil evidence is an auxiliary peice of evidence.
Fossil evidence is not testable due to the fact that it can be incomplete. Also fossils usually do not preserve soft tissue, which makes it difficult to determine if the fossils belong to different species.
Fossil lineages are likewise disputable because of the above mentioned facts. It is because of analysis of living species today that we are able to speculate on fossil lineages.
Natural selection is a conclusion reached on the folowing observations.
All life produces far more offspring than the environment can support.
All living things pass on their traits to their offspring.
Therefore not all offspring will survive and therefore whatever allows certain individuals to procreate while others do not is termed natural selection.
If anyone has an alternative conclusion to some individuals surviving while others do not, I am open to sugestions.
It's akin to a group of students. There is limit to approved applications to top Universities. Some of those students will not get into the a top university. There must be somthing determining who goes and who does not. Of course in the chaotic natural world this process is more haphazard and less clear.
The preponderance of evidence and testable hypothesys' lies with living organisms.
As for how natural selection is testable, I struggle with that a bit too. maybe I'm just being stupid and don't quite understand what you meant.
Before we get to the conclusion, can you maybe explain the first of your two premises a bit more? How do we know that all life produces for more offspring than can be supported?
I am also confused by how your conclusion proves the testability of natural selection? No offspring survives in the long run, and I struggle to see how individuals living longer necessarily translates into a superior ability to procreate and pass on suitability across a population, and how that creates biochemical pathways to new species. Apart from that, the whole conclusion seems to be circular: Which individuals are allowed to procreate? Those who survive the longest. Who survives the longest? Those who are allowed to procreate. How is that testable?
Sure as heck confuses me.
Acts 17:24-25 (NIV)
"The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. [25] And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else."
//www.omnipotentgrace.org
//christianskepticism.blogspot.com
"The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. [25] And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else."
//www.omnipotentgrace.org
//christianskepticism.blogspot.com
-
- Established Member
- Posts: 116
- Joined: Thu Nov 17, 2005 9:40 am
- Christian: No
- Location: Carbondale, IL
The first question is easily answered in that no organisms exhibit a life history strategy wherein all offspring survive to maturity and in turn reproduce. Each habitat has factors that act as a check on populations; such factors include disease, predation, food limitation, etc. that tend to increase with population size. It is these factors, as well as other factors such as environmental conditions and genetic aspects, that determine which offspriing will survive to reproduction.August wrote:Before we get to the conclusion, can you maybe explain the first of your two premises a bit more? How do we know that all life produces for more offspring than can be supported?
I am also confused by how your conclusion proves the testability of natural selection? No offspring survives in the long run, and I struggle to see how individuals living longer necessarily translates into a superior ability to procreate and pass on suitability across a population, and how that creates biochemical pathways to new species. Apart from that, the whole conclusion seems to be circular: Which individuals are allowed to procreate? Those who survive the longest. Who survives the longest? Those who are allowed to procreate. How is that testable?
Your idea of no offspring surviving in the long run is incorrect in terms of gene flow. Obviously, no individual is immortal, but if if an individual reproduces successfully it has passed on some of its genetic material, so in this way the aspects of successful individual do outlive the actual individual. The most successful individuals are not those who live the longest, but those who produce the most offspring that then reproduce themselves. As a quick example of how something like this might be tested, both from a natural selection perspective and an evolution perspective, consider this:
You have two species of deer whose ranges meet in the the middle of a country, call them species 1 and 2. Natural selection would predict that each species would be best suited to their local habitat, so let's say species 1 is best suited to survive the rugged mountainous terrain around the Rocky mountains while species 2 is best suited to survive the warmer climate of the Southeast U.S. By looking at their reproductive strategies across their respective ranges we can make inference to how natural selection has shaped the two species. We would predict that species 1 should have thicker fur, bigger body size, etc. to handle the colder climate, while the converse should be true for species 2; where the ranges meet, we may predict that an intermediate condition is favored. The next step would be to actually look at these species to see if the predictions of morphology are correct, as well as look at their reproductive strategies to see if, for example, the furriest individuals are the most reproductively successful in the Rockies and the smaller individuals are the most successful in the Southeast. Also, if we see a gradual transition whereby the two species are very similar where there ranges meet, that would provide further support for our assumptions of natural selection shaping these species.
From an evolutionary perspective, one way of testing whether these two species evolved from one another or a common ancestor would be to look at genetic data. If, for example, you look at a certain sequence of DNA and find that that sequence becomes more and more different as you move towards each coast from the center of the country, it could support a theory that at one point an ancestral species existed where the ranges meet in the middle. This theory could also be tested by determining whether individuals that live where the ranges meet can interbreed while those on the coasts cannot; if this is observed, it would support a theory that the species may have been one and gradually split due to expanding ranges and different environmental conditions. You can also use genetic data to test whether these species came from a common ancestor that may still be present, for if the genetic information between species 1 and 2 is similar where there ranges meet AND similar to a third species that inhabits this area, one theory may be that these two species evolved from the third species.
This is just an example, and I generalized quite a bit on the methods because they are quite complicated and specific to the specific questions being addressed, but this is just one example of how natural selection and evolution can be tested. I should point out that nowhere in my post did I use the word "prove"; it is a word I see thrown around a lot from both pro- and anti-evolutionists, but no theory can ever be proven or disproven. You can only provide support for your argument or for another.
- BGoodForGoodSake
- Ultimate Member
- Posts: 2127
- Joined: Mon Aug 29, 2005 9:44 am
- Christian: No
- Location: Washington D.C.
The fossils themselves are evidence. The lineage and relations between them is an application of the theory and is therefore not evidence, and as you said cannot be tested to a certain extant. The only way to test it is for future fossil findings to fall within reasonable lines. Seeing that the evidence is not complete there is always leeway for changing divergence dates etc. Making testing very questionable. However if lets say homo sapien bones are found among dinosaur bones then it presents problems. But I see what your saying about testability.August wrote: Hi Bgood, thanks for the response. So we agree that the fossil lineage evidence is not testable, and therefore cannot be submitted as proof for evolution.
We know this because offspring die before reaching sexual maturity. If organisms do not produce enough offspring to replace the current generation logically there will be no future generations.August wrote:As for how natural selection is testable, I struggle with that a bit too. maybe I'm just being stupid and don't quite understand what you meant.
Before we get to the conclusion, can you maybe explain the first of your two premises a bit more? How do we know that all life produces for more offspring than can be supported?
This only requires survival long enough to procreate.August wrote:I am also confused by how your conclusion proves the testability of natural selection? No offspring survives in the long run,
Individuals are unique.August wrote:and I struggle to see how individuals living longer necessarily translates into a superior ability to procreate and pass on suitability across a population,
We know some mutations are harmful, this may cause an individual to perish before reaching sexual maturity, thus removing the harmful mutation from the gene pool.
Mutations which are not harmful will pass on to the next generation.
The collection of nonharmful mutations increases and changes the gene pool throughout time. This allows a population to have more variety(traits).August wrote:and how that creates biochemical pathways to new species.
For example we have a group of rats. One has a mutation in their blood protein. Another has a mutation in fur color. And a third has a mutation in eyesight. The one with the eye mutation is blind and does not survive very long. The other two however survive and pass on their genes. After several generations these particular genes have been spread throughout the population.
The rat population has begun migration north, during this time period as the weather has been exceptionally warm. Then the weather patterns change and the weather becomes considerably colder. This has a significant impact on the rat population. It turns out that the minor change in the rats blood protein allows it to function in the cold weather, and the rats without this gene perish. All subsequent generations of rats now have this gene. The population decimated quickly grows back as resources are plentiful. However the population is now isolated from the main rat population by the unusual weather changes. Rats with the fur mutation are better able to cope with the cold and over time their offspring has a better chance of survival than those individuals without this mutation (which is now a trait).
The one's which are able to procreate.August wrote:Apart from that, the whole conclusion seems to be circular: Which individuals are allowed to procreate?
It is easy to test. Select a trait you wish to give selective advantage. Lets say big feet. Now raise some mice and actively select for large feet. After several generation you should expect to see the average foot size increase. Of course this will only work on traits which actually exist.August wrote:Those who survive the longest. Who survives the longest? Those who are allowed to procreate. How is that testable?
August wrote:Sure as heck confuses me.
It is not length of life, but depth of life. -- Ralph Waldo Emerson
- AttentionKMartShoppers
- Ultimate Member
- Posts: 2163
- Joined: Tue Feb 15, 2005 8:37 pm
- Christian: Yes
- Sex: Male
- Location: Austin, Texas
- Contact:
Lineage? What lineage? Cannot be tested.The fossils themselves are evidence. The lineage and relations between them is an application of the theory and is therefore not evidence, and as you said cannot be tested to a certain extant. The only way to test it is for future fossil findings to fall within reasonable lines. Seeing that the evidence is not complete there is always leeway for changing divergence dates etc. Making testing very questionable. However if lets say homo sapien bones are found among dinosaur bones then it presents problems. But I see what your saying about testability.
And relationship (as in similarity I assume) means nothing-it is evidence for nothing. And, you seem to say there can only be negative evidence against, never positive evidence for, evolution, through the fossil record.
"My actions prove that God takes care of idiots."
He occasionally stumbled over the truth, but hastily picked himself up and hurried on as if nothing had happened.
- On Stanley Baldwin
-Winston Churchill
An atheist can't find God for the same reason a criminal can't find a police officer.
You need to start asking out girls so that you can get used to the rejections.
-Anonymous
He occasionally stumbled over the truth, but hastily picked himself up and hurried on as if nothing had happened.
- On Stanley Baldwin
-Winston Churchill
An atheist can't find God for the same reason a criminal can't find a police officer.
You need to start asking out girls so that you can get used to the rejections.
-Anonymous
- August
- Old School
- Posts: 2402
- Joined: Wed Dec 29, 2004 7:22 pm
- Christian: Yes
- Sex: Male
- Creation Position: Day-Age
- Location: Texas
- Contact:
Hi thereal and Bgood,
Thanks for your replies, but you still have not answered the question about the testability of natural selection as a mechanism for evolution.
Natural selection requires variation in a trait, fitness differences in consistent relation to the trait, and the trait be heritable. So while you showed the standard evolutionary story of how environmetal pressures act on organisms which then somehow are seen as better suited to that environment, it still does not show testability. The variations have to occur in the loci that regulates the control network of the organistic ontogeny. So what is needed to test natural selection, is to demonstrate the presence of heritable variation throughout early ontogeny, and to show thus how mutagenesis can be the basis for adaptive variation.
thereal:
Darwin himself said:"It may be said that natural selection is daily and hourly scrutinising, throughout the world, the slightest variations; rejecting those that are bad, preserving and adding up all that are good; silently and insensibly working, whenever and wherever opportunity offers, at the
improvement of each organic being in relation to its organic and inorganic conditions of life.
Some have even imagined that natural selection induces variability, whereas it implies only the preservation of such variations as arise and
are beneficial to the being under its conditions of life. . . . In the literal sense of the word, no doubt, natural selection is a false term."
From the quote it is clear that even Darwin knew that natural selection only preserved changes, but does not itself have the ability to create variability.
Bgood:
In all, the examples which you spent so much time writing, which I appreciate, did not show the testability of natural selection as a mechanism for evolution. It demonstrated microevolution nicely, described genetic variances on which natural selection can or cannot act, but not how that can be tested, merely how it is supposed to work. It does not account for why or how procreation happened in the first place, and how mutations of the simplest lifeforms lead to the complexity of life seen today, how does it account for eyes, ears, gender etc? After all, natural selection only preserves, without purpose.
Thanks for your replies, but you still have not answered the question about the testability of natural selection as a mechanism for evolution.
Natural selection requires variation in a trait, fitness differences in consistent relation to the trait, and the trait be heritable. So while you showed the standard evolutionary story of how environmetal pressures act on organisms which then somehow are seen as better suited to that environment, it still does not show testability. The variations have to occur in the loci that regulates the control network of the organistic ontogeny. So what is needed to test natural selection, is to demonstrate the presence of heritable variation throughout early ontogeny, and to show thus how mutagenesis can be the basis for adaptive variation.
thereal:
While that is a nice theory that I have heard several times, it requires some nifty footwork to accomplish it over a complete biocosm. And it repeats back to me what I said, that the successful individuals are the ones that procreates best, while the ones that procreates best are the successful ones. But it does not explain how it tests natural selection.Your idea of no offspring surviving in the long run is incorrect in terms of gene flow. Obviously, no individual is immortal, but if if an individual reproduces successfully it has passed on some of its genetic material, so in this way the aspects of successful individual do outlive the actual individual. The most successful individuals are not those who live the longest, but those who produce the most offspring that then reproduce themselves.
I have several issues here, but will stivck with the main one for now. How does natural selection predict anything? It has no transcendent properties, it is merely an arandom blind process acting on current impulses. The same question applies to how it can shape anything?You have two species of deer whose ranges meet in the the middle of a country, call them species 1 and 2. Natural selection would predict that each species would be best suited to their local habitat, so let's say species 1 is best suited to survive the rugged mountainous terrain around the Rocky mountains while species 2 is best suited to survive the warmer climate of the Southeast U.S. By looking at their reproductive strategies across their respective ranges we can make inference to how natural selection has shaped the two species. We would predict that species 1 should have thicker fur, bigger body size, etc. to handle the colder climate, while the converse should be true for species 2; where the ranges meet, we may predict that an intermediate condition is favored. The next step would be to actually look at these species to see if the predictions of morphology are correct, as well as look at their reproductive strategies to see if, for example, the furriest individuals are the most reproductively successful in the Rockies and the smaller individuals are the most successful in the Southeast. Also, if we see a gradual transition whereby the two species are very similar where there ranges meet, that would provide further support for our assumptions of natural selection shaping these species.
Darwin himself said:"It may be said that natural selection is daily and hourly scrutinising, throughout the world, the slightest variations; rejecting those that are bad, preserving and adding up all that are good; silently and insensibly working, whenever and wherever opportunity offers, at the
improvement of each organic being in relation to its organic and inorganic conditions of life.
Some have even imagined that natural selection induces variability, whereas it implies only the preservation of such variations as arise and
are beneficial to the being under its conditions of life. . . . In the literal sense of the word, no doubt, natural selection is a false term."
From the quote it is clear that even Darwin knew that natural selection only preserved changes, but does not itself have the ability to create variability.
A fine description of micro-evolution, but still does not say anything about how homology of DNA accounts for the testability of natural selection. In fact, I have in another thread argued that genetic homology is not testable or falsifiable since there are no defined margins of variation that would falsify it.From an evolutionary perspective, one way of testing whether these two species evolved from one another or a common ancestor would be to look at genetic data. If, for example, you look at a certain sequence of DNA and find that that sequence becomes more and more different as you move towards each coast from the center of the country, it could support a theory that at one point an ancestral species existed where the ranges meet in the middle. This theory could also be tested by determining whether individuals that live where the ranges meet can interbreed while those on the coasts cannot; if this is observed, it would support a theory that the species may have been one and gradually split due to expanding ranges and different environmental conditions. You can also use genetic data to test whether these species came from a common ancestor that may still be present, for if the genetic information between species 1 and 2 is similar where there ranges meet AND similar to a third species that inhabits this area, one theory may be that these two species evolved from the third species.
Bgood:
The fossils themselves are evidence only of the presence of an organism at a specific point in time. Fossil lineage is considered the evidence for gradual changes over time, and I am yet to see how that can be tested.The fossils themselves are evidence. The lineage and relations between them is an application of the theory and is therefore not evidence, and as you said cannot be tested to a certain extant. The only way to test it is for future fossil findings to fall within reasonable lines. Seeing that the evidence is not complete there is always leeway for changing divergence dates etc. Making testing very questionable. However if lets say homo sapien bones are found among dinosaur bones then it presents problems. But I see what your saying about testability.
I'm not sure how that answers my question, but ok. If all life produced more than could be supported, why do we see extinction? Logically, all organisms should survive if all life produced more than could be supported. I was just curious, as I always am when I see the word "all".We know this because offspring die before reaching sexual maturity. If organisms do not produce enough offspring to replace the current generation logically there will be no future generations.
This only requires survival long enough to procreate.
So are you saying that harmful mutations do not pass on, and precludes the organism from procreating? To suggest natural selection happens purely by eliminating harmful mutations through lack of procreation does not explain it when tested against empirical observation.Individuals are unique. We know some mutations are harmful, this may cause an individual to perish before reaching sexual maturity, thus removing the harmful mutation from the gene pool. Mutations which are not harmful will pass on to the next generation.
But that still does not answer my question, how does natural selection account for biochemical pathways to new species? No-one is debating that within species differentiation happens, but it does not account for new phyla, for example. And while nonharmful mutations increase, since the overwhelming majority of mutations are neutral or harmful, those will increase at the same rate.The collection of nonharmful mutations increases and changes the gene pool throughout time. This allows a population to have more variety(traits).
I guess all of your preceding info can be captured here. The problem I have with this is that if I select a trait, that is adding an outside influence or purpose into the process, and then I agree, it can easily be done. But natural selection does not have purpose, or any other transcendental characteristics, so while your experiment may work, it does not test natural selection, it tests Bgoods selection. And why should it work for traits only actually exist? Surely genetic manipulation will allow you to grow a gills on a mouse, since it is genetically homologous with sharks, through a common ancestor?It is easy to test. Select a trait you wish to give selective advantage. Lets say big feet. Now raise some mice and actively select for large feet. After several generation you should expect to see the average foot size increase. Of course this will only work on traits which actually exist.
In all, the examples which you spent so much time writing, which I appreciate, did not show the testability of natural selection as a mechanism for evolution. It demonstrated microevolution nicely, described genetic variances on which natural selection can or cannot act, but not how that can be tested, merely how it is supposed to work. It does not account for why or how procreation happened in the first place, and how mutations of the simplest lifeforms lead to the complexity of life seen today, how does it account for eyes, ears, gender etc? After all, natural selection only preserves, without purpose.
Acts 17:24-25 (NIV)
"The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. [25] And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else."
//www.omnipotentgrace.org
//christianskepticism.blogspot.com
"The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands. [25] And he is not served by human hands, as if he needed anything, because he himself gives all men life and breath and everything else."
//www.omnipotentgrace.org
//christianskepticism.blogspot.com
- BGoodForGoodSake
- Ultimate Member
- Posts: 2127
- Joined: Mon Aug 29, 2005 9:44 am
- Christian: No
- Location: Washington D.C.
Mutations and novel combinations of existing traits provide additions to variability.August wrote:Hi thereal and Bgood,
Thanks for your replies, but you still have not answered the question about the testability of natural selection as a mechanism for evolution.
Darwin himself said:"It may be said that natural selection is daily and hourly scrutinising, throughout the world, the slightest variations; rejecting those that are bad, preserving and adding up all that are good; silently and insensibly working, whenever and wherever opportunity offers, at the
improvement of each organic being in relation to its organic and inorganic conditions of life.
Some have even imagined that natural selection induces variability, whereas it implies only the preservation of such variations as arise and
are beneficial to the being under its conditions of life. . . . In the literal sense of the word, no doubt, natural selection is a false term."
From the quote it is clear that even Darwin knew that natural selection only preserved changes, but does not itself have the ability to create variability.
It cannot, however one can see that organisms from one period are different from another. And organisms in subsequent periods seemed to be based on body designs of those in earlier periods.August wrote: Bgood:The fossils themselves are evidence only of the presence of an organism at a specific point in time. Fossil lineage is considered the evidence for gradual changes over time, and I am yet to see how that can be tested.The fossils themselves are evidence. The lineage and relations between them is an application of the theory and is therefore not evidence, and as you said cannot be tested to a certain extant. The only way to test it is for future fossil findings to fall within reasonable lines. Seeing that the evidence is not complete there is always leeway for changing divergence dates etc. Making testing very questionable. However if lets say homo sapien bones are found among dinosaur bones then it presents problems. But I see what your saying about testability.
Extinction is the end of a species. No doubt the dodo created more offspring than needed to maintain the population given the conditions did not change, however human interference caused them to go extinct. These are two separate matters.August wrote:I'm not sure how that answers my question, but ok. If all life produced more than could be supported, why do we see extinction?We know this because offspring die before reaching sexual maturity. If organisms do not produce enough offspring to replace the current generation logically there will be no future generations.
Organisms produce more offspring than are needed to replace the current population.
This does not preclude a species from going extinct due to new pressures which the species could not cope with.
Let me know if that didn't clear it up.
Again this is not the case. You are using two different meanings of the idea. Simply, all life forms produce more offspring than is expected to survive. If there are sudden changes in conditions the whole species may be threatened, thus leading to extinction.August wrote:Logically, all organisms should survive if all life produced more than could be supported.
I hope it is all clear now.August wrote:I was just curious, as I always am when I see the word "all".
I am saying if something prevents the organism from passing on their genes then it will not pass onto the next generation. This includes harmful genes.August wrote:This only requires survival long enough to procreate.So are you saying that harmful mutations do not pass on, and precludes the organism from procreating?Individuals are unique. We know some mutations are harmful, this may cause an individual to perish before reaching sexual maturity, thus removing the harmful mutation from the gene pool. Mutations which are not harmful will pass on to the next generation.
This is not what I suggested. I stated that non-harmful genes will persist in the population. I used the two examples for contrast, see next quote.August wrote:To suggest natural selection happens purely by eliminating harmful mutations through lack of procreation does not explain it when tested against empirical observation.
But that still does not answer my question, how does natural selection account for biochemical pathways to new species?[/quote]Multiple micro-evolution events.August wrote:quote]The collection of nonharmful mutations increases and changes the gene pool throughout time. This allows a population to have more variety(traits).
New phyla do not suddenly occur. They are defined as a phyla because they are so morphologically different. Imagine we have a clay ball and a class of children. Next we create another clay ball like the first. We pass the balls around and ask each child to make one tiny change to the ball. After going around a few times we have two different clay balls. If we then make many copies of each ball and have people make slight changes to each copy, we can expect clay balls from one copy to be similar to each other. And likewise for the second group. We can then say we have two phyla of balls.August wrote:No-one is debating that within species differentiation happens, but it does not account for new phyla, for example.
Not if by definition harmful mutations cause mortality or infertility.August wrote:And while nonharmful mutations increase, since the overwhelming majority of mutations are neutral or harmful, those will increase at the same rate.
Very well, however in nature are there no pressures for living animals?August wrote:I guess all of your preceding info can be captured here. The problem I have with this is that if I select a trait, that is adding an outside influence or purpose into the process, and then I agree, it can easily be done. But natural selection does not have purpose, or any other transcendental characteristics, so while your experiment may work, it does not test natural selection, it tests Bgoods selection.It is easy to test. Select a trait you wish to give selective advantage. Lets say big feet. Now raise some mice and actively select for large feet. After several generation you should expect to see the average foot size increase. Of course this will only work on traits which actually exist.
No, selection only works for existing traits within a population.August wrote:And why should it work for traits only actually exist?Surely genetic manipulation will allow you to grow a gills on a mouse, since it is genetically homologous with sharks, through a common ancestor?
May I ask given a large number of microevlution events why won't speciation not occur?August wrote:In all, the examples which you spent so much time writing, which I appreciate, did not show the testability of natural selection as a mechanism for evolution. It demonstrated microevolution nicely, described genetic variances on which natural selection can or cannot act, but not how that can be tested, merely how it is supposed to work.
This can be speculated but given that the fossil record is majority hard material like bones we cannot know how an eye developed. However the variety of eyes within the natural world can give us clues. The inability to explain how specific things evolved only shows the limitations of our knowledge.August wrote:It does not account for why or how procreation happened in the first place, and how mutations of the simplest lifeforms lead to the complexity of life seen today, how does it account for eyes, ears, gender etc?
Organisms alive today owe their existance to the successful procreation of their parents.August wrote:After all, natural selection only preserves, without purpose.
It is not length of life, but depth of life. -- Ralph Waldo Emerson
-
- Established Member
- Posts: 116
- Joined: Thu Nov 17, 2005 9:40 am
- Christian: No
- Location: Carbondale, IL
I think Bgood pretty much summed up what I was going to say about this, but your thoughts on survival of "all" in terms of species is not the same as survival of "all" in terms of a population. Extinction of species can even be considered further support for selection (some do not wish to call it natural because humans are causing it) as some species are better suited than others to survival the environmental onslaught that is mankind.August wrote:I'm not sure how that answers my question, but ok. If all life produced more than could be supported, why do we see extinction? Logically, all organisms should survive if all life produced more than could be supported. I was just curious, as I always am when I see the word "all".
August wrote:I have several issues here, but will stivck with the main one for now. How does natural selection predict anything? It has no transcendent properties, it is merely an arandom blind process acting on current impulses. The same question applies to how it can shape anything?
You are exactly right in assuming natural selection is a blind process in the sense that an organism is not changing to reach a certain "perfect form"; the changes are random in the sense that they are dictated by such things as environmental condition, sexual selection strategy, etc. This is a common misconception by many that animals are evolving "towards" something. The predictive value of natural selection does not lie in determining what the animal should look like in 1000 years given its present form, but how features of an animal should be expected to respond to a certain change in its environment. First comes change in environment, then the change in the organism.
This is not a circular argument as you insinuate, as the first meaning of "successful" and the second are not the same. This definition would be more clearly stated "the successful individuals (those that pass on the most genetic material to the next generation) are the ones that procreate best, while the ones that procreate best are the successful ones (those that possess characteristics that make them best suited to the current environment).August wrote:While that is a nice theory that I have heard several times, it requires some nifty footwork to accomplish it over a complete biocosm. And it repeats back to me what I said, that the successful individuals are the ones that procreates best, while the ones that procreates best are the successful ones. But it does not explain how it tests natural selection.
Why can morphological characters not be used to this end, such as fur length, color, defenses. You do not need to introduce new mutations to test natural selection...existing characteristics can be examined for this purpose. It would be great to examine the whole process from beginning to end (introduce mutation that is beneficial given the current environment, see those individuals with that mutation reproducing relatively more than those without, watch it spread in the population while other forms of that gene either remain static or decrease, etc.) This would show both natural selection and evolution (as evolution is simply a change in allele frequency over time). To see this in nature would be incredibly difficult and time consuming, as mutations occur randomly, you would need to be lucky to find the right population, response to environmental change lags behind the actual changes, etc. Although many of these separate components have been tested in the lab, for some reason I can't understand, this seems inadequate to those who don't believe these processes happen.August wrote: So what is needed to test natural selection, is to demonstrate the presence of heritable variation throughout early ontogeny, and to show thus how mutagenesis can be the basis for adaptive variation.
I have a real problem when people identify something as microevolution while not believing in macroevolution. These are one in the same, just different degrees of evolution. It's like saying I believe in an embryo developing into the gastrula stage, then the gastrula eventually developing into a fetus, etc...but I don't believe that an embryo can develop into an adult. How can many microevolutionary events not lead to macroevolution? Maybe it's due to the impatience of humans that they want to see this process in their lifetime, but it's not going to happen....this process takes time.August wrote:A fine description of micro-evolution, but still does not say anything about how homology of DNA accounts for the testability of natural selection
"Without purpose" meaning goal, yes, you're correct. However, the "purpose" or more appropriately, result, of natural selection is to create a population best suited to their existing environment.August wrote:After all, natural selection only preserves, without purpose.
RE:
This still does not answer many deep questions about evolution, such as HOW did the body become realized? WHY was it realized? Why couldn't they have stayed ameobas? WHY was there evolution to begin with? And the things like the eyes and the ears, it still does not give much reason why. These things are transcendal, their aim is to provide a function for something beyond rather than within. You still don't convince me with your 'explanation' of transcendant evolution, even humans challenge this greatly.
Much of your theory is taken on faith as you claim ID and others are taken on faith. There may be substantial micro-evolutions, but the fact is they are still in the same species. There are animals that have been around for years like dogs, cats, etc., and they have always been what they are, even in the most indifferent forms. Like with fish, the fishes are still fishes. The idea of them even transcending into non-sea creatures is ridiculous and is lacking in both science and philosophy.
The idea of the environment alone influencing it is limited, because most theories about transcendant evolution are weak.
Much of your theory is taken on faith as you claim ID and others are taken on faith. There may be substantial micro-evolutions, but the fact is they are still in the same species. There are animals that have been around for years like dogs, cats, etc., and they have always been what they are, even in the most indifferent forms. Like with fish, the fishes are still fishes. The idea of them even transcending into non-sea creatures is ridiculous and is lacking in both science and philosophy.
The idea of the environment alone influencing it is limited, because most theories about transcendant evolution are weak.
"And I shall slay them who partake of futurism, for in the preterist light there will be everlasting salvation, truth, and peace." ~ Faust
-
- Established Member
- Posts: 116
- Joined: Thu Nov 17, 2005 9:40 am
- Christian: No
- Location: Carbondale, IL
By "realized", I'm assuming you mean developed or something similar...not quite sure, so if I'm wrong let me know. As far as why we couldn't just have amoebas forever, there are a lot of reasons why change is good. Competition is one...if everyone has the same life history strategy, then doing something different through changes in morphology, behavior, genetics, etc. could be beneficial (it could also be detrimental). For example, if every amoeba has the same tolerances to temperatue and thus couldn't travel to a certain part of their environment because of harsh conditions, a change that allowed an individual to move into these previously uninhabited area would provide a relief from competition...with relieved competitive pressure may come increased reproduction and thus the beneficial change spreads. Things like eyes and ears are more developed structures but they arose for the same reasons as my hypothetical new amoeba with different temperature tolerance...these things are beneficial in one way or another. I'm not saying that in one generation you have an organism with no eyes and in the next an organism with fully developed eyes...these changes take time and many creationists can't even consider the idea of the earth being billions of years old, so I wouldn't expect any consideration of the ridiculously slow pace at which these changes occur. However, even if you look back from complex to simpler organisms that exist today, it may provide a rudimentary diagram of how these changes may have taken place over time...complex eyes in humans, pineal eyes in reptiles, photoreceptors in flatworms, phototactic responses in zooplankton, etc.Ark~Magic wrote:This still does not answer many deep questions about evolution, such as HOW did the body become realized? WHY was it realized? Why couldn't they have stayed ameobas? WHY was there evolution to begin with? And the things like the eyes and the ears, it still does not give much reason why. These things are transcendal, their aim is to provide a function for something beyond rather than within.
Ark~Magic wrote:Much of your theory is taken on faith as you claim ID and others are taken on faith. There may be substantial micro-evolutions, but the fact is they are still in the same species. There are animals that have been around for years like dogs, cats, etc., and they have always been what they are, even in the most indifferent forms. Like with fish, the fishes are still fishes. The idea of them even transcending into non-sea creatures is ridiculous and is lacking in both science and philosophy.
So a cheetah is the same as a tiger, domestic cat, margay, cougar, etc. No...they are all cats (Family Felidae) thought to have descended from a common ancestor, but htey are obviously not the same. If you're talking domestic dogs and cats, then there are several problems with your argument. First, your statements that "they have been around for years" lets me know that you are not even considering the time span the theory of evolution requires. It's like saying "I know this plant isn't growing because I've been watching it for an hour now". Your assertion that they "have always been what they are" is simply an opinion. Second, humans have only been domesticating these animals for a few thousand years, and look at the tremendous variation we have (eg. bulldogs, siberian husky, bloodhound) and they were originally thought to have come from a common ancestor...given how selective breeding occurred for these breeds, it is obvious that they at least came from more morphologically similar origins. We can see the changes in morphology due to selective breeding even today as breeders select for taller dogs, shorter dogs, certain colors, etc., so your assertion that they were always that way is obviously false. Given the drastic changes that have occurred in such a short time span, can you honestly tell me that you see no way in which these changes could pile up over a few million years to the point where they could no longer interbreed?
As far as your statement of fish changing into non-fish and how this is ridiculous...let me set ask you a question. Why are the bones structures of marine mammals, such as whales and pinnipeds, more similar to terrestrial mammals than to fish. ToE hypothesizes that these groups arose from terrestrial mammals and intermediate skeletal forms are even evident in the fossil record...let alone that fact that these are marine organims that must breathe air (a terrestrial trait). I know this is the reverse of your statement with fish turning into non-fish, but I would honestly like to hear your suggestion of why this is. Just to say that an air-breathing creature with terrestrial features was created and dropped into an aquatic medium seems, pardon the pun, a little "fishy" to me.
RE:
First of all you kind of missed what the hell I was trying to get across in the first place but that [poop] is difficult to express.
One thing is that the fossil evidence is insufficient, as has been explained here to support the theory. The timeline in which many things are said to have evolved is off and inconsistent. And I don't feel like repeating this stuff again.
For some good opinions on evolution from an old-earth perspective (or just general perspective) give this site a shot: http://www.reasons.org
One thing is that the fossil evidence is insufficient, as has been explained here to support the theory. The timeline in which many things are said to have evolved is off and inconsistent. And I don't feel like repeating this stuff again.
Again, more ignorance about creationism, you're thinking young-earth....these changes take time and many creationists can't even consider the idea of the earth being billions of years old, so I wouldn't expect any consideration of the ridiculously slow pace at which these changes occur.
For some good opinions on evolution from an old-earth perspective (or just general perspective) give this site a shot: http://www.reasons.org
"And I shall slay them who partake of futurism, for in the preterist light there will be everlasting salvation, truth, and peace." ~ Faust
-
- Established Member
- Posts: 116
- Joined: Thu Nov 17, 2005 9:40 am
- Christian: No
- Location: Carbondale, IL
Thanks for the website link. It did give me a better perspective of where you're coming from, but I can say that it does get confusing when you have to stop and ask which form of creationism someone follows before trying to discuss things. Not to go too far off topic, but on that note, why is it that there is little observeable debate between the different schools of thought concerning creation(Young earth, old earth, flat earth). To play the devil's advocate, someone has to be wrong, don't they?August wrote:Again, more ignorance about creationism, you're thinking young-earth.
For some good opinions on evolution from an old-earth perspective (or just general perspective) give this site a shot: http://www.reasons.org
Anyway, although I appreciate your providing this link, I am getting less and less surprised to discover the scientific staff backing most of these creationist sites never have anyone from the fields of ecology, animal behavior, ecomorphology, or any form of life sciences. They are always physicists or theologians...just from the perspective of someone in the life sciences field, it's hard to take someone talking about evolution and creation seriously that has no background in life sciences. I also noted that this site is directly misleading regarding evidence for evolution. As one example, I quote:
"A newly discovered example of biological convergence challenges the evolutionary paradigm. Since chance serves as its mechanism, evolution should not produce the same outcome repeatedly. If the clock of history could be rewound, evolution would take a different pathway. Yet study after study shows that repeated outcomes are routine. Researchers have discovered the repeated, independent origin of nocturnality in prosimians (lower primates such as lemurs). This discovery challenges the veracity of the theory of evolution, but affirms the idea that a Creator repeatedly used the same good designs-in this case animals that function nocturnally-as He brought new life forms into existence"
This argument is flawed from the beginning...evolution does not predict different outcomes each time...if the selective pressures affecting organisms are the same. For instance the similarities between many of the placental mammals of South America and the marsupials of Australia would be attributed to similar environmental conditions. The idea of convergent evolution is not something new in the field of biology, and the arguments provided by this site show either misrepresentation of, misunderstanding of, or a basic ignorance of established biological concepts. Sorry to get so worked up about a simple website, but with this type of information provided to people, it's no wonder there is a general misunderstanding about evolutionary processes in general!
RE:
Here is another, more diverse, but really good website, sir:
http://www.asa3.org/
Here are others:
http://www.doesgodexist.org
Also, did you check THIS site out? I hope you did.
And I hope this helps.
http://www.asa3.org/
Here are others:
http://www.doesgodexist.org
Also, did you check THIS site out? I hope you did.
And I hope this helps.
"And I shall slay them who partake of futurism, for in the preterist light there will be everlasting salvation, truth, and peace." ~ Faust