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Leevan

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I've recently read a couple of books that were critical of evolution, and it has caused me to review my understanding of life and its creation. Obviously, there is no question that plants and animals adapt, the strongest/smartest survive, beneficial traits are passed from generation to generation, etc. But to change from one animal to another, even over time, requires an incredible and almost unbelievable amount of mutations. One has no trouble believing that anything can happen with enough time, but the fossil records indicate that the time frame for the debut of species' is relatively short. For such changes to occur so quickly and in concert (cambrian explosion), makes me wonder 'how' and 'why'.

 

I don't think there is a god, but the way it looks, to me, is almost as if life was pre-programed or guided. Could evolution and life in general have had a helping hand? Or, at least, is 'evolution' a faulty theory?

 

 

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We have only to look at a few decades to see species change in profound ways through selection. Look at dog breeds, or chicken breeds, or even cats. Nature is also a selector, but the more profound changes that lead to breeds that can no longer produce fertile offspring takes a bit longer (the dividing line for species is the fertility aspect). Horses and donkeys cannot produce fertile offspring, so they are different species instead of different breeds, but we are not amazed that they can make offspring at all.

 

https://dogbehaviorscience.wordpress.com/2012/09/29/100-years-of-breed-improvement/

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The fossil records make it look like the party both stopped and started for a massive amount of species at specific, (relatively) short time spans. Extinction, ok, I get that. Meteor goes boom; everything dies. But what about the emergence part? How can that happen so quickly? The possibilities are endless with evolution, and that's the problem. More time would be needed, it seems, to orchestrate historic and current lifeforms.

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Evolution is the best explanation we have for the diversity of species.  It is more probable that the time available to evolution was sufficient for the diversity of species we see today (and the millions of extinct species) rather than some other influence that we have no evidence of.

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We have only to look at a few decades to see species change in profound ways through selection. Look at dog breeds, or chicken breeds, or even cats. Nature is also a selector, but the more profound changes that lead to breeds that can no longer produce fertile offspring takes a bit longer (the dividing line for species is the fertility aspect). Horses and donkeys cannot produce fertile offspring, so they are different species instead of different breeds, but we are not amazed that they can make offspring at all.

 

https://dogbehaviorscience.wordpress.com/2012/09/29/100-years-of-breed-improvement/

I will go ahead and reiterate that you should look at what we can do to dog breeds.  Drastic changes in a species can happen fascinatingly quick.

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Obviously, there is no question that plants and animals adapt, the strongest/smartest survive, beneficial traits are passed from generation to generation, etc. But to change from one animal to another, even over time, requires an incredible and almost unbelievable amount of mutations.

 

This is a misconception as most changes in evolution are not the result of mutations, but rather the result of natural selection. Changes via mutation would be extremely slow, but natural selection is much faster as it simply requires genetic variance within a population.

 

With enough time, you could breed a large number of vastly different animals through artificial selection. The DNA base structure would look the same as mutation isn't involved, but the DNA instructions would be very different.

 

Though not an extreme example, all of the different dog breeds we have now draw from the same gene pool as wolves. This is to say that the genes for a pitbull, the genes for a corgi, and any other dog you can think of were already in the gene pool, it just took some selection to bring out those particular traits.

 

If we to start breeding dogs to be good at swimming, the dogs with their hind limbs further back will likely be the most successful. The dogs whose feet are more able to push against water will also be more successful. Over a number of generations, the hind limbs would move further and further back, to the point where they may fuse together. Of course what I am getting at is that you could create an animal which has the DNA structure of a dog, but is actually like a seal.

 

What is interesting about this is that you could say that there are the instructions for creating a seal like animal within the wolf population, but that the instructions just need to be arranged in the right way. This concept can be taken further to say that you could create almost anything by combining the right instructions.

 

Richard Dawkins has a great book called The Blind Watchmaker that explains a lot of this better than I can.

The fossil records make it look like the party both stopped and started for a massive amount of species at specific, (relatively) short time spans. Extinction, ok, I get that. Meteor goes boom; everything dies. But what about the emergence part? How can that happen so quickly? The possibilities are endless with evolution, and that's the problem. More time would be needed, it seems, to orchestrate historic and current lifeforms.

 

The fossil record can provide great insight, but there are also many limitations. For instance, it can give the impression of lots of life emerging all at once, when it is instead that the conditions for fossilization greatly increased which lead to more fossils. Organisms might be transitioning from soft bodies which would not be capable of fossilizing, to hard bony bodies that are capable of fossilizing. There could have been more diversity prior to the Cambrian explosion, but that life might have just not have been as well suited to fossilize.

 

As Dawkin says, it is amazing that we any fossils at all. Though the fossil record can help us understand a lot about evolution, the theory of evolution by natural selection can easily stand on its own without any fossils supporting it.

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The fossil records make it look like the party both stopped and started for a massive amount of species at specific, (relatively) short time spans. Extinction, ok, I get that. Meteor goes boom; everything dies. But what about the emergence part? How can that happen so quickly? The possibilities are endless with evolution, and that's the problem. More time would be needed, it seems, to orchestrate historic and current lifeforms.

 

Besides that Pepin said, there punchuated equlibrium by Steven J. Gulld (spellin?) Id suggest him up and his research, be wary of creationist quote miners thoguh, he has received fair shake of those since PE is dare i say it, evolution of our understanding of evolution whaich of many things Darwin didnt know.

 

Also fossilization is rare, so there will be gaps in the fossil record. And with sudden starts if youre refering to say the Cambrian era, when lots of life emerged quickly this period is around 20-25 million years, give or take but within that time so much life emerged which we know today. And even then MOST of those species are dead and exintct.

 

The sudden chances on climate or enviroment weed out those not capable of surviving in it be it evident physical charestirictics or intelligence or mutual cooperation during harsh times. Like mammals for example survived where as dinosaurs didnt...except as birds and not all birds are dinosaurs and those with feathers. And when this occured the amounth of species of those mammals and proto birds was in hungreds/thousends so... :)

 

...so if fossilization wasnt rare then the amounth of species we have found would pose problem with time, however since most species that are dead never fossilized evolution hasnt jsut had lots of time but als loooooots and lots of variation. To the point where every single million years was filled with thousends of chances iun enviroment to million upon millions of species and KLIDES to not say the least! :D

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Epigenetics also play a major role here. The DNA molecule is mostly made out of junk DNA but some of that DNA was once used by some ancestral creature. A shift in the conditions of the environment leads, or may lead, to activation/inactivation of such genes thus we do not always need to wait for genes to mutate for a species to adapt to the environment, the genes required might already be there from the beginning of life. 

 

For instance, in the Madagascar there are several species resembling other species found everywhere else on Earth BUT the Madagascarian species aren't directly related to any other species outside of Madagascar. The species have a resemblance because they evolved under very similar environmental conditions.

 

Or fish for example. The species "fish" simply does not exist even though they all look the same. One species of fish can have as much in common with another as do giraffes and humans even though they're look incredibly similar. They look the same because they live in the same type of environment.

 

If we were to create a colony of humans on the Moon after just a couple of generations we would end up with something quite different though 100%human. The lower gravitational pull of the moon will lead to much taller humans, they will probably have a paler complexion and harrier bodies due to a lack of heat, I'm just speculating here of course.

 

Like it was emphasized above, changing one animal into another isn't that far of a stretch if we just look at dog breeds. A different looking animal does not imply a different species, corgis and grayhounds are still both dogs. Furthermore the fossil records can be misleading because a lot of animals have developmental stages. Future paleontologists might categorize a human baby to be of a different species to a human adult. This is what happened to several species of dinosaurs that were proven to not exist, they got recategorized into earlier stages of development of other existing species. Or a more extreme example are butterflies and caterpillars. Same species, "different" animals altogether.

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What books have you read which are critical of evolution? I think it would be interesting to learn more about them.

 

Well, the initial author that caused me to question evolution was Ann Coulter in 'Godless'. (The latter half of the book evaluates the theory of evolution. The book itself is a critique of leftists.) I looked into her points, and they seem logical and coherent.

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What are those gaps?

 

The lack of transitional fossils for example. Given that evolution, according to Darwin, is/was a continual process, it follows that the fossil record should have no shortage of transitional forms. And again, the Cambrian explosion doesn't really fit in with the theory. The transitions from spineless creatures to...everything in the Cambrian era seems to be relatively short. With the lack of transitional fossils, it almost looks as if it switched from one to another.

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The lack of transitional fossils for example. 

 

There is no lack of those. 

 

 

Given that evolution, according to Darwin, is/was a continual process, it follows that the fossil record should have no shortage of transitional forms.

 

 

Again, no lack. Can you back this up with references? 

 

And again, the Cambrian explosion doesn't really fit in with the theory. 

 

Well, I am afraid to say that the Cambrian explosion is a prime example. During the Cambrian Explosion, the first occurance of the Hox genes happened. This discovery of those regulatory genes caused a huge leap forward in the biological sciences. http://en.wikipedia.org/wiki/Hox_gene

 

The transitions from spineless creatures to...everything in the Cambrian era seems to be relatively short. 

 

 

Short, compared to?

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There is no lack of those. 

 

 

Again, no lack. Can you back this up with references? 

 

Well, I am afraid to say that the Cambrian explosion is a prime example. During the Cambrian Explosion, the first occurance of the Hox genes happened. This discovery of those regulatory genes caused a huge leap forward in the biological sciences. http://en.wikipedia.org/wiki/Hox_gene

 

 

Short, compared to?

I haven’t researched the subject thoroughly. From what I’ve come across, I’ve observed that there is a significant shortage of transitional fossils. If you have a reference that cites otherwise, I would be grateful.

 

As for the Cambrian explosion, it is believed to have lasted ten million years. So, that gene you mentioned must be one hell of a gene. For it to come about when it did, and have such far reaching consequences so quickly is what causes me to question the possibility of *something* unknown.

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The fact that fossils aren't commonplace doesn't assuage my concerns. Yes, evolution is logical, and it seems to be a fit answer; but, when I'm asked to base my certainty on (essentially) faith, I cringe.

 

This is slightly off topic--but not completely:  The book Race, Evolution, and Behavior by J. Philippe Rushton is a fascinating read. The author examines the physical differences among Asians, Whites, and Blacks. (He does have pretty legit cred.) If you look into it, I'd go for the unabridged version. That one has all the citations, etc.

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The fact that fossils aren't commonplace doesn't assuage my concerns. Yes, evolution is logical, and it seems to be a fit answer; but, when I'm asked to base my certainty on (essentially) faith, I cringe.

 

Why doesnt it?

 

So far i and others have talked about facts, when was "faith" in any shape or form entered the discussion?

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The fact that fossils aren't commonplace doesn't assuage my concerns.

 

My response wasn't intended to assuage your concerns; it was to correct something you said.

 

In the vast majority of cases of fossil discovery, there is no trace of the organism. Circumstances have to be right for a fossil to form. If you're looking for transitional fossils like cells in a movie reel then you're not going to find them.

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The lack of transitional fossils for example. Given that evolution, according to Darwin, is/was a continual process, it follows that the fossil record should have no shortage of transitional forms. And again, the Cambrian explosion doesn't really fit in with the theory. The transitions from spineless creatures to...everything in the Cambrian era seems to be relatively short. With the lack of transitional fossils, it almost looks as if it switched from one to another.

 

No, not at all. It is a miracle there are any fossils as the circumstances needed to create a fossil are hard to come by. This is why when there are the right circumstances, you get a lot of the same sort of specimens from around the same time. Look into how fossils form if you are interested in that.

 

Also to reiterate, fossils can lend some support, but they aren't needed to prove evolution. If the conditions on earth were so that no fossils could form, the theory of evolution would be just as accepted because the theory of evolution doesn't have anything to do with fossils.

 

Having fossils is great as you can illustrate how evolution works by pointing out a very large number of species in transitions and gain a lot of knowledge into how life evolved, but they simply aren't needed to prove that evolution is true. Dawkins has a great book where he actually makes a case for evolution without reference to fossils.

 

If you want possible explanations of the Cambrian Explosion, either read some Dawkins or at the very least this wiki page. It isn't like it is some imaginable embarrassment, it is rather just an area of intrigue. But seriously, read some Dawkins. I can assure you that you don't have an understanding of evolution.

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For you to push aside Alan's link with such ease, Leevan, says something about your constructiveness in this discussion.

 

Also, every fossil you find is a "transition fossil" because every form that ever existed has had a slight difference in everything about it.

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Thanks Leevan for posting this topic, as I have also read a few books that have caused me to question our understanding of the evolutionary process.  Two of these books are by Stephen C Meyer, and provide the most scientific and rational arguments against the currently accepted evolutionary theory that I have found so far, with absolutely no religious agenda.  While these books do mention some of the standard arguments such as gaps in the fossil record, the major theme of both books deals with the creation of large amounts of "functionally specified information"; that is, information that is arranged in a specific sequence that produces a specific effect, such as the specific arrangement of letters to form words that convey thoughts to other human beings, or the arrangement of bits on a DVD that will result in a specific output when run by a computer.  Here is a relatively brief summary of the arguments proposed in his latest book, Darwin's Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design, as it is most relevant to this post.

 

- Improbability of the creation of new genes and proteins by random mutation: The probability of creating a new functional protein from an existing functional protein through random mutation is astronomically small.  The studies that are referenced in the book give the ratio of functional to nonfunctional proteins as 1 in 1063 and 1 in 1077 for a relatively small protein containing 150 amino acids.  Given that only about 1040 organisms have existed in all of Earth's history, it seems rather improbable that the multitude of functional proteins required to generate multiple phyla of animal life could be created in a few million years.

 

- Complex Adaptations:  Many features of animals require an integrated system of body parts to confer some selective advantage.  For example, fruit flies have been mutated in the lab to have an extra set of wings; however, for this mutation to be advantageous, it would have to simultaneously evolve the muscles and nerves to use the new wings, otherwise it is a selective disadvantage.  Evolution of many new animal body plans over a few million years would require numerous simultaneous mutations to numerous systems of integrated parts; systems that would become useless or disadvantageous should one of the parts be missing or changed.  This argument also applies to what are known as developmental gene regulatory networks, which control how individual cells develop, are organized, and interact with each other during embryonic development.  Small changes to these networks always result in catastrophic consequences for the organism, and the simultaneous creation of a new gene network would be required to evolve a new phylum or class of animals.

 

- Epigenetic Information: Additional information crucial to animal development is stored outside of the DNA.  Examples include the skeletal structure of the cell, the pattern of proteins in the cell membrane, arrangement of channels through which charged particles can pass through, and arrangement of sugar molecules on the exterior of the cell membrane.  Creation of a new animal body plan will require simultaneous changes in these factors as well as in the DNA. 

 

His other book is Signature in the Cell: DNA and the Evidence for Intelligent Design, which deals with more with the origin of life or the creation of information in DNA.  As this post is getting quite long, I’ll leave this one for another time.

 

He concludes that the only reasonable explanation for these changes is a conscious mind, since this is the only known cause of a drastic increase in functionally specified information, of which an incomprehensible amount is required to create an animal from a single celled organism.  Regardless of whether you agree with this conclusion, I encourage anyone who thinks that evolution is a settled science to read these books. 

 

My first exposure to Stephen Meyer was on the Coast to Coast AM show; I attached the episode where he discusses this book (June 19, 2013).  The books are over 400 pages each, so this show is a good intro if you don't want to commit the time to reading the books. 

 

Coast to Coast - Jun 19 2013 - Hour 2.mp3

Coast to Coast - Jun 19 2013 - Hour 3.mp3

Coast to Coast - Jun 19 2013 - Hour 4.mp3

 

This is my biggest obstacle on the road to strong atheism, so refutation of these arguments may get you a new convert, though I don’t really believe in a god in the traditional sense.  These are only brief summaries of the arguments made in the book, so I will be more than happy to elaborate on any of these points. 

 

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Romulox, I appreciate the effort you put into your post.

 

I'm not exactly knowledgeable to argue against the first point as it is a technical one.

 

The second point is where things get a little confusing because though there are events which can give the impression of very fast complex adaptation, when it is more likely to be turning on of dormant genes. The dormant genes will have already gone through the whole staggeringly slow evolutionary process and simply need to be activated.

 

There is also a sort of adaptation where it uses the same code to create duplicate appendage. To create an extra pair of wings, you don't need to go through the whole evolutionary process to create that extra pair of wings, rather you can just use the already existing wing code. How it might work in practice is that a gene simply allows the stem cells which create the wings to split a second time, leading to the creation of a second pair of wings. These sort of birth defects are somewhat common, and some small percentage of the time they are beneficial.

 

To go a little further with that, genes that would inhibit a second pair of wings might also be beneficial. It may be beneficial for a particular species of squid to reduce the number of arms they have as the amount they currently need isn't needed. In humans, there is a gene for a sixth finger which lies dormant for the vast majority of the population.

 

The third point I can't figure out a way to argue against because I can't fathom a physical reason why all of the instructions can't be encoded in the DNA. This is omitting a few of the various complexities of mitochondrial DNA which can somewhat be considered "non-human" DNA from a technical point of view.

 

Have you read any of Dawkin's books? I'd read a couple as they are really quite good. It is really vital to understand the interplay of non-mutation components in natural selection, as they do the majority of the work. Mutations play a key role of course, but they aren't exactly the main focus.

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Lets assume for a moment that these numbers are correct (they are not; it takes a lot less proteins to form a self replicating protein, the starting point for evolution). This mindboggling number does not tell you when the unlikely event happens. It could be right at the start, at the middle, or at the end. In addition, there is not one trial to produce these protobiotic form, but billions, namely everywhere where the conditions are given. It is unlikely that you throw 10000000000 times a coin and you get heads up every time. But imagine billions of people doing that for a long time and it is to be expected. 

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- Epigenetic Information: Additional information crucial to animal development is stored outside of the DNA.  Examples include the skeletal structure of the cell, the pattern of proteins in the cell membrane, arrangement of channels through which charged particles can pass through, and arrangement of sugar molecules on the exterior of the cell membrane.  Creation of a new animal body plan will require simultaneous changes in these factors as well as in the DNA.

 

 

This statement is posed as if those other factors only change one at a time, or only exist in a vacuum separate from each other.

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Thanks, everyone, for your input. It seems to be a more complicated subject than most people realize, which is why I question/ed the knee-jerk reactions via the proponents of the theory.

 

It is not a knee jerk reaction, it is actually the exact opposite of a knee jerk reaction.

 

As has been explained, evolution is the best theory we have for the diversity of species based on evidence.  This is how science works.  There is no evidence except speculation that there was any other external influence in the process of evolution, therefore this would be considered a hypothesis in search for evidence.  Science, in order to avoid knee jerk reactions, bases theories on demonstrable/reproducible evidence and will only entertain this as a theory once evidence is produced.  Until that time, it will remain outside the realm of science.

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I have not actually read any of Dawkins' books, but since nearly every other argument Meyer raises typically involves a Dawkins quote, he is definitely on my list.  Which of his books do you recommend that are most relevant to this issue? Does he have any articles, videos, or podcasts that focus on non-mutational selection or the problems of the Cambrian explosion and the origin of DNA and life?

 

The second point is where things get a little confusing because though there are events which can give the impression of very fast complex adaptation, when it is more likely to be turning on of dormant genes. The dormant genes will have already gone through the whole staggeringly slow evolutionary process and simply need to be activated.

 

How does the evolutionary process create these genes in the first place if they have never been expressed?  With regards to the Cambrian explosion, why would there be genes for jointed limbs, compound eyes, and 50+ new cell types in a single celled organism or even a simple animal like a sponge, whose ancestors have never had these features?  Again, you would be counting on random mutations to create these genes, this time without selective pressure to promote them (since they were never expressed in the past), which would take far longer than even the 3 billion years that life has existed prior to that (see 1077 discussion in the first post).  Also, since many of these genes form complex integrated systems, if one of these dormant genes were mutated or did not activate in concert with the others, the organism would almost certainly be disadvantaged.

 

 

There is also a sort of adaptation where it uses the same code to create duplicate appendage. To create an extra pair of wings, you don't need to go through the whole evolutionary process to create that extra pair of wings, rather you can just use the already existing wing code. How it might work in practice is that a gene simply allows the stem cells which create the wings to split a second time, leading to the creation of a second pair of wings. These sort of birth defects are somewhat common, and some small percentage of the time they are beneficial.

 

To go a little further with that, genes that would inhibit a second pair of wings might also be beneficial. It may be beneficial for a particular species of squid to reduce the number of arms they have as the amount they currently need isn't needed. In humans, there is a gene for a sixth finger which lies dormant for the vast majority of the population.

 

I completely agree that these types of changes in an existing animal population can result from the mutation/selection process.  The problem I see is equivalent to changing that existing wing code in a way that will produce a fully functional human arm.  It's not that natural selection isn't capable of creating new features or species, it's that it can't account for the astronomical increase in complexity and information needed to create 20+ new animal phyla in a few million years. 

 

 

 

The third point I can't figure out a way to argue against because I can't fathom a physical reason why all of the instructions can't be encoded in the DNA. This is omitting a few of the various complexities of mitochondrial DNA which can somewhat be considered "non-human" DNA from a technical point of view.

 

I'll need to re-read the section on epigenetics and get back to you later, as that section gets quite technical and I don't quite understand it as much as I would like.

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