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I will answer every question about evolution you have

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posted on Jan, 1 2016 @ 02:15 AM
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originally posted by: Heronumber0
a reply to: Ghost147
However, I saw that the presence of a system of neurons pre-existed before the evolution of the eye in each case. How did this occur? Why should neurons go to locations where there was no stimulus?


Could you cite the exact information your confused about?


originally posted by: Heronumber0
a reply to: Ghost147
Finally, using the paradigmatic gradualistic and natural selection motif, what are the selection pressures which would kill off all organisms that have poor mechanisms for detecting light when we still have these organisms existing today quite happily?


Well, these organisms you speak of have adapted to their environments, so they are the the successful offspring of their previous generation and have all the necessary adaptations so survive there. There isn't really a universal 'selective pressure' that would simply rid us of all those organisms either, because each of their environments are different, and each of those organisms have adapted separately to those environments. So the only thing that would really kill them off is if each and everyone of of their environments were to change so dramatically that it killed all the individual populations.

This could happen if, say, the planet exploded, or was engulfed by the sun, or what have you. However, organisms are extremely resilient, we know of some that eat radiation as a main source of food, we know of some who's internal organs run on acid, we know of some who live in acid, and we know of some that can live in space. So even with a detrimental event on Earth, it's quite possible that 'something' could live on the rubble in space, or simply become dormant.




posted on Jan, 1 2016 @ 06:52 PM
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Happy New Year to you and your family. Please address all the points I made in my original post. I am a believer in a Creator to maker my position clear but I am also fairly open minded to how creation occurred. If you do not understand parts of the post, let us teach each other in an atmosphere of cooperation and friendship- Peace



posted on Jan, 1 2016 @ 07:22 PM
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originally posted by: Heronumber0
If you do not understand parts of the post, let us teach each other in an atmosphere of cooperation and friendship


It's not that I don't understand the question, it's that I'm not quite sure which part of the article you mentioned you found to be odd. So, if you could cite that particular part, I can address it with a bit more clarity.



posted on Jan, 1 2016 @ 10:40 PM
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originally posted by: Heronumber0
a reply to: Ghost147

I scanned the wiki link on the eye quite quickly so I could be confused on this. However, I saw that the presence of a system of neurons pre-existed before the evolution of the eye in each case. How did this occur? Why should neurons go to locations where there was no stimulus?


This is because prior to the advent of complex eyes during the Cambrian, the first photosensitive cells existed in unicellular organisms called eye spots. The primary function of these early eye spots was for synching the organism up with circadian cycles and photoperiodism, but they can trace their origins back even farther to photosynthetic cells of early phytoplankton. Per your question, the stimulus existed prior to the Cambrian and the massive degree of biodiversity that erupted just over a half billion years ago and it was a very slow progression initially, over a period of a couple billion years leading up to the Cambrian.



I was of an understanding that any chromophore would need to be recycled in order for re-use (such as retinol). This would need a system of enzymes and chemical potential energy reagents such as GTP or ATP which could utilise free energy in order to regenerate the chromophore.


Perhaps I'm missing something because it's late, but I'm not sure what chromphores, which absorb light and exhibit colors that the eye can see, have to do with the question. Please feel free to clarify this aspect for me so it can be appropriately addressed. Thank you.


Finally, using the paradigmatic gradualistic and natural selection motif, what are the selection pressures which would kill off all organisms that have poor mechanisms for detecting light when we still have these organisms existing today quite happily?



Would it be safe to assume that you're asking why there are still organisms with less developed systems of light detection when so much of todays biodiversity has developed complex systems of vision? If I am incorrect here, please let me know and I will attempt to appropriately address your true intent. If I am correct then...

First and foremost, selection pressures, contrary to how a lot of people seem to view the process, is a rather conservative aspect of MES. The fewer selection pressures, the more variation you will see. Much like we do in the design for eyes as there are a multitude of morphological and functional presentations. From Turbellarian worm eyes, to human eyes, to the compound eye of the fruit fly, each is adapted to suit the needs of the organism in question. If there are no issues with predation and the organism in question is not decimated by said predation, there is no need to adapt as there is no threat to the organisms current state of existence. In instances where these organisms are indeed killed off as you put it in your query, the 'selection pressure' in question is going to be predation by species with better vision that can track their prey.

Then you have organisms such as the Mexican Tetra. One species of this Tetra is better known as a blind cave fish. The gene regulating eyesight, shape and function is present whether looking at the sighted variant or the blind variant. There is a protein called HSP90. It binds to other proteins to keep them properly folded. Work done at MIT has demonstrated that when HSP90 is distracted, as may occur when an organism is stressed by a new environment, certain traits that were uniform in a stable environment begin to show a great deal of variation in the new environment. While more research into this needs to be done, the suggestion is that HSP90 holds proteins in a certain shape and in doing so, compensates for minute variations that have built up in the genome over time. When the organism becomes stressed due to environmental fluctuations(like being in a cave and cut off from sunlight), HSP90 becomes diverted and the alternate forms of these proteins are released, triggering a response leading to wide variance in traits. Natural selection then acts on these new traits leading to adaptation events.

In an experiment done by the MIT researchers, they raised the surface dwelling variety of the Mexican Tetra in water treated with a blocking agent inhibiting HSP90 which led to a wide variance in both eye and socket sizes. An additional experiment in which another group of surface dwelling Tetras were raised in water from an underground system in which the cave dwelling tetras lived found that the offspring yielded an even wider variety of eye sizes.

At the end of the day, organisms exhibiting archaic features are analogous to Amish still using a horse and buggy on the same roadway as a modern sports car like a Lexus R8. If there is no impetus to change, then change will not occur.



posted on Jan, 2 2016 @ 06:29 PM
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a reply to: peter vlar

Hi Peter, you gave me an excellent answer and I wish to respond to it. As a former postdoctoral scientist, I have had a brief gander at MES and have worked on pure molecular genetics topics but still retained my belief in a Creator whilst all around me completely accepted the MES and neo-Darwinian beliefs. Even superior philosophers like Hegel could not explain the diversity in Nature though a system of logic and reason.

The Cambrian era and billions of years of changes are normally sufficient for people to believe in evolutionary science without a murmur. However, I need a bit more explanation. I am puzzled at eye development because I cannot see how the following points occur:

1. Why would sensory neurons develop in an area where there was no eye? Were the sensory neurons there to detect pressure or temperature and then switched to detecting light?
2. Why would a small number of light detecting cells with no connection to the motor systems of an organisms confer a selective advantage to it at all? If you can detect light but not respond to it what is the point of having it in a multicellular organism?
3. How could a photosensitive molecule (not chromophore - it was getting late) be regenerated without the enzymes and molecules for regenerating the photoreceptor/photosensitive molecules?
4. Is there a natural selection for a half eye with no neural links?
5. Is there room to abandon gradualistic selection arguments here?

I am not saying gee look at the complexity. God did it! I am saying God did it! But how?
Could the Cambrian have been planned by an Absolute Intelligence who then let it happen and left His Laws of Nature in charge?

I don't know the answer, but I wil meet arguments honestly and genuinely. I will address the rest of your super answer later once I reflect on it.

How the eye detects light - rhodopsin



edit on 2/1/2016 by Heronumber0 because: Tried to put in an image and it did not work



posted on Jan, 5 2016 @ 11:39 AM
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a reply to: Heronumber0


I have had a brief gander at MES and have worked on pure molecular genetics topics but still retained my belief in a Creator whilst all around me completely accepted the MES and neo-Darwinian beliefs.


What neo-darwinian beliefs? MES isn't a belief system, so there is no need to have faith in it or have beliefs about it. This is one of the biggest misconceptions about evolution. That it requires blind faith and is atheistic. Both are false. There's no reason why you can't believe in a creator, yet also still accept the science behind Modern Evolutionary Synthesis.


Even superior philosophers like Hegel could not explain the diversity in Nature though a system of logic and reason.


Evolution is science, not philosophy. People LOVE to act like philosophy overrides hard evidence in science, but it doesn't. It's like asking what if, rather than what is. Are you trying to say that genetic mutation and natural selection defy logic and reason, even though both have been directly observed in countless organisms by biologists and geneticists?

As for your other questions:

1. You are approaching MES incorrectly. You are asking why rather than how. Science answers the how, the why can be whatever belief system you want, there isn't always an answer to the why. Again, I see an attempt to equate philosophy to science. Evolution relies on random genetic mutations, there doesn't have to be a reason for them to happen, although there are causes. They are random, they are beneficial, the trait gets passed down. It's not that complicated. You are asking why they emerged in the first place. Likely, it was just random and it stuck because it helped an organism survive longer and hence procreate more, passing the helpful trait down.

2. Of course they would be connected to the rest of the organism. What makes you think that the ability to detect light wouldn't affect numerous aspects of an organism's survival? I could list a bunch of them, but don't see a reason to state the obvious. What makes you think that they can detect light but not respond to it? I'm having a little difficulty understanding your point here.

3. This one I will leave to the experts on here. I'm not a chemist, but see no issue whatsoever with the scientific explanation of the mechanics of evolution on the molecular level. What needs to be regenerated and why?

4. Again, there is no half eye, and why do you say there are no neural links? It's not a half eye, it's an eye that is not fully developed, in an intermediary stage where it may not have vision like ours today, but can still detect light and benefit from it. The stages of eye development have already been posted in this thread. Please reference that chart and tell us what stage you are talking about.

5. Nope. Gradualism makes too much sense and has been shown in many organisms. Don't get me wrong, punctuated equilibrium is a real phenomenon, so not every single change is slow and gradual. There are other mechanisms involved as well that aren't fully understood yet, but not knowing every single detail about everything doesn't make it wrong.


edit on 1 5 16 by Barcs because: (no reason given)



posted on Jan, 5 2016 @ 04:37 PM
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a reply to: Barcs

Hi Barcs, you have not really answered any point and are taking an aggressive stance here when I have clearly stated my position. You have not really answered my questions scientifically and have resorted to the stereotype in these debates and you ask me to have faith in your system of reason and logic but probably don't realise it. Every PhD is a doctor of philosophy including me. Philosophy from Aristotle onwards set the foundations for subsequent hypothetico deductive methods, is scientific method.
I will read your post more thoroughly and get back to you.
Thanks
Peace



posted on Jan, 5 2016 @ 09:52 PM
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originally posted by: Heronumber0
a reply to: Barcs

Hi Barcs, you have not really answered any point and are taking an aggressive stance here when I have clearly stated my position. You have not really answered my questions scientifically and have resorted to the stereotype in these debates and you ask me to have faith in your system of reason and logic but probably don't realise it. Every PhD is a doctor of philosophy including me. Philosophy from Aristotle onwards set the foundations for subsequent hypothetico deductive methods, is scientific method.
I will read your post more thoroughly and get back to you.
Thanks
Peace


I wasn't trying to be aggressive, I was trying to be thorough in answering each point. I tend to over explain things at times and I apologize for that. Please let me know which points you take issue with, I thought I addressed your points pretty thoroughly aside from #3. If you need me to source anything, I'd be happy to.

Yes, I agree that philosophy has helped build science and that modern science uses philosophy to come up with new ideas. I wasn't trying to downplay that. Philosophy is great for coming up with new ideas, but the science part is where the ideas go from hypothetical to tested and verified. A philosopher's inability to understand the logic of how evolution creates diversity does not change the evidence that shows it happening right in front of our eyes, so I was confused by the quote about Hegel. Perhaps I misunderstood what you said.
edit on 1 5 16 by Barcs because: (no reason given)



posted on Jan, 5 2016 @ 10:28 PM
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originally posted by: Heronumber0
a reply to: peter vlar

Hi Peter, you gave me an excellent answer and I wish to respond to it. As a former postdoctoral scientist, I have had a brief gander at MES and have worked on pure molecular genetics topics but still retained my belief in a Creator whilst all around me completely accepted the MES and neo-Darwinian beliefs.


By your language and syntax, I had assumed that you had done some graduate level work. As a person of faith, your personal views are just that, personal. As long as one adheres to the Scientific Method and understands how to separate personal faith from adherence to proper scientific inquiry, there should be no issue. My Mother in-law worked at the Human Genome Project until they went public. The head of the project was Dr. Francis Collins. He's one of the worlds leading geneticists and worked on decoding our genome. He is also a devout Christian. His faith didn't come into play at work and he adhered strictly to the rigors of the Scientific Method and consequently, his work stands for itself. Faith doesn't need to be a burden on scientific inquiry, though it far too often seems to be the case when disingenuous groups like ICR and AIG begin using half baked science to support unscientific notions that only convinces those suffering from confirmation bias and a decided lack of education or at least, willful ignorance towards how the science actually works. These people are quite fond of putting forth "Dr. so and so who has a PhD" as an expert on a particular topic. Yet when you look a little farther, you will find that it's someone who is disseminating data in a field completely unrelated to their chosen field. One example that I recall is using a Geologist, who did in fact have a doctoral, writing an essay disputing Chemistry or Genetic based data. As an Anthropologist, I never wrote about what was wrong with aspects of Physics I disagreed with because I knew where the line in the sand lay regarding what I could confidently comment on as well as support. And how many papers have these people submitted to journals for review? None. But the rubes eat it up because their confirmation bias is supported by someone with a PhD. As for your last sentence here, there are no Neo-Darwinian beliefs or belief systems. There is science and peer reviewed data. I don't dicker with beliefs, I report what the data says, what it supports and what the degree of review has been done to confirm the validity of said data. there are no beliefs regarding MES, only facts supported by data.



Even superior philosophers like Hegel could not explain the diversity in Nature though a system of logic and reason.


attempting a philosophical explanation for hard science never works though. one either addresses the data or they attempt to create a philosophical rationale for it. the 2 concepts don't typically find much middle ground in my experience.


The Cambrian era and billions of years of changes are normally sufficient for people to believe in evolutionary science without a murmur. However, I need a bit more explanation. I am puzzled at eye development because I cannot see how the following points occur:



Perhaps that is so for the majority of laymen but for me, particularly with recent advancements in genetic testing and the ability to do higher coverage runs in far quicker time has demonstrated an unmistakable level of confirmation supporting the facts of evolution. You can ignore the fossil record, the geology, stratigraphy etc... the genetics alone are an unquestionable piece of the puzzle that confirms everything else.


1. Why would sensory neurons develop in an area where there was no eye?


because as I mentioned earlier, the earliest precursors to the eye were eyespots in the Stigmas of phytoplankton. I don't know how much experience you have with horticulture but its a little hobby of mine. Even basic garden variety plants like the tomato will move and bend towards their source of light to maximize exposure of photoreceptive cells increasing the amountof energy taken in during photosynthesis. These plants will literally bend their stalks as they follow the sun across the sky. If working with an indoor garden, they will do the same thing though the light source may be stationary. I've had plants that will completely reorient their stalks or certain branches to gain access to more light. Even if they are in this position for weeks, leading to a very pronounced bend in the branch or stalk, if you move the light source, they will again move to accommodate.

The more simplistic answer to your query of "why" would be that these early organisms had these eyespots as a way of synching circadian rhythms and differentiating between day and night. Just like many modern organisms, these early unicellular organisms based when they would mate, or in their case asexually reproduce, based on solar and lunar cycles.


Were the sensory neurons there to detect pressure or temperature and then switched to detecting light?


There isn't any evidence to suggest that. In larger multicellular organisms, there are many ways of determining pressure and temp. Skin being a primary source of the above.



2. Why would a small number of light detecting cells with no connection to the motor systems of an organisms confer a selective advantage to it at all? If you can detect light but not respond to it what is the point of having it in a multicellular organism?


As I mentioned above with my plant analogy, there was an advantage conferred. Those who could sense the direction light was coming from, in addition to beginning circadian adaption and differentiation between day and night, those who could find where the source of light originated, could maximize their energy potential by increasing access to light for photosynthesis.

We can also look at the reverse of this. Take Astanax Mexicanus for example. It is a Mexican Tetra fish. One variety lives in rivers, the other lives in underground caves. The cave dwellers are more popularly known by the colloquialism of Blind Cave Fish. Both the surface and cave dwelling variants have the exact same sets of genes. It is the expression of those genes that makes all the difference. But what causes this varied gene expression? Recent work done at MIT has found that a protein called HSP90 is the most likely culprit here.

What HSP90 does is it binds to other proteins to ensure that they are properly folded and assures that they maintain a specific shape. When an organism encounters stressors, like a rapid environmental shift, that HSP90 becomes distracted from engaging in its primary function. Where certain traits were once uniform in a species, a distracted HSP90 leads to expression of a wide variation in many traits. Natural selection then is able to act on those traits to select for the most advantageous ones in the new environment. continued...



posted on Jan, 5 2016 @ 10:28 PM
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originally posted by: Heronumber0
a reply to: peter vlar



continued from above...
A second study conducted at Harvard Medical School found that when surface tetra were treated in water with an HSP90 blocker, that those fish exhibited wide variation on morphological expression. Particularly the size of the eyes and the sizes of the eye sockets. An additional study conducted by the same lead author doing the above mentioned HSP90 blocker study found that surface tetras treated with water that was chemically similar to the caves inhabited by the blind tetras, again, exhibited a similar variation in eye morphology.

Another interesting aspect of Astyanax Mexicanus is that the lack of eyes saves them energy, which is another beneficial adaptation resulting from their lack of a circadian rhythm and as a result of less available food supplies in their ecological niche, this was a rather important adaptation. Particularly in light of( No pun intended) the very low genetic diversity they exhibit, especially compared to their surface dwelling cousins.




3. How could a photosensitive molecule (not chromophore - it was getting late) be regenerated without the enzymes and molecules for regenerating the photoreceptor/photosensitive molecules?


The simple answer is that these enzymes would have developed quite early just as the eyespots did. Beyond that, I can't give a more definitive answer. Unlike creation scientists, I'm not going to blow smoke up your posterior nad make a claim beyond what I can say with a high degree of veracity. My background is in paleoanthropology so while I do have a lot of information on the development of the eye, this is something I don't know enough about to properly comment on.






4. Is there a natural selection for a half eye with no neural links?


There really is no such thing as half an eye. Each step in the evolution of complex eyes has a function leading up to what we see in the variety of eyes exhibited in modern organisms. from the monochromatic eyes of canines, to the eyes of humans to compound eyes of a fruit fly to the very different compound eyes in trilobites to nonspherical lenses with a refractive cornea, appositional corneas, superpositional corneas and on and on and on...

Ghost147 did a pretty good job of showing these varying developmental stages earlier in the thread.



5. Is there room to abandon gradualistic selection arguments here?


I am a supporter of Punctuated Equilibrium. If the evidence supports a less gradual adaptive development then yes. But gradualism is not the exception, it is the norm by and large.


I am not saying gee look at the complexity. God did it! I am saying God did it! But how?


certainly, that is your prerogative to believe this. But to get to that point, you should first have evidentiary support showing the existence of god and more so, which god it is prior to simply accepting that this is a foregone conclusion and then jumping to the how without supporting the 'is god real' portion of the equation. This is the equivalent of attempting to solve an equation without supplying either the equation or the formula.


Could the Cambrian have been planned by an Absolute Intelligence who then let it happen and left His Laws of Nature in charge?


from a purely scientific perspective, it would be dishonest to rule out any possibility. with that said, evidence must support the possibility of such an occurrence existing. So, yes, god could have done it. But if he did, why are there so many flaws? Sticking with the eye example... why would he give humans such crappy vision? why would he place all of the veins in the eye so near the surface? It makes no sense that a magical, all powerful being of pure perfection is such a F' up


edit on 5-1-2016 by peter vlar because: tags are my nemesis



posted on Feb, 29 2016 @ 04:59 PM
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a reply to: Ghost147

How would you define a gene, and the role it plays in evolution?



posted on Feb, 29 2016 @ 05:14 PM
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originally posted by: PhotonEffect
a reply to: Ghost147

How would you define a gene, and the role it plays in evolution?


A gene is a specific sequence within DNA (not the full strand of DNA, but a portion of it).

In more technical terms it's a distinct sequence of nucleotides forming part of a chromosome, the order of which determines the order of monomers in a polypeptide or nucleic acid molecule which a cell (or virus) may synthesize.

The DNA that consists of these genes play a massive role on how mutations are expressed within an organism, and those expressions can dictate how likely it is for that organism to survive in a particular environment.

Genes can also undergo mutations themselves, and when reproduction occurs, these new mutations can spread throughout a particular generation. If the organism benefits from this mutation, they have a higher chance of reproducing, therefore passing on these genes. If the organism receives a disadvantage from this mutation, then they have a less likely chance of reproducing, therefore the disadvantageous genes may be weeding out of the population.



posted on Feb, 29 2016 @ 06:11 PM
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originally posted by: Ghost147

The DNA that consists of these genes play a massive role on how mutations are expressed within an organism, and those expressions can dictate how likely it is for that organism to survive in a particular environment.

How "massive" of a role would you say? And without trying to put words in your mouth, are you suggesting that traits are solely the result of 'mutations' being expressed (as you put it)?


originally posted by: Ghost147
Genes can also undergo mutations themselves, and when reproduction occurs, these new mutations can spread throughout a particular generation. If the organism benefits from this mutation, they have a higher chance of reproducing, therefore passing on these genes.

Why should this be put forth only in terms of genetic mutation? Don't beneficial traits derive from other ways?


originally posted by: Ghost147
If the organism receives a disadvantage from this mutation, then they have a less likely chance of reproducing, therefore the disadvantageous genes may be weeding out of the population.

Hmmm, R2d2?

Do you believe that genes are selfish?



posted on Feb, 29 2016 @ 07:18 PM
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a reply to: Barcs


originally posted by: Barcs
What neo-darwinian beliefs? MES isn't a belief system, so there is no need to have faith in it or have beliefs about it. This is one of the biggest misconceptions about evolution.

Actually, if – despite what research over the last decade is bearing out – you continue to put the entire emphasis on MES/Neo-Darwinism as the principles governing all evolutionary processes, then yes, it is akin to a belief system. Because the manner in which these ideas dictate how evolution occurs, mostly as a matter of genetic mutation & natural selection, is actually only a fraction of how it works, yet it ignores all the rest. Much like you've done in this post.



originally posted by: Barcs
There's no reason why you can't believe in a creator, yet also still accept the science behind Modern Evolutionary Synthesis.

That's why he said that he accepted both.


originally posted by: Barcs
1. You are approaching MES incorrectly.

Indeed.


originally posted by: Barcs
Evolution relies on random genetic mutations, there doesn't have to be a reason for them to happen, although there are causes. They are random, they are beneficial, the trait gets passed down. It's not that complicated.

First of all, it is very complicated, actually. This is the problem – your view of evolution, which is the prevailing one, is a gross oversimplification of the process. You put all emphasis on genetic mutation. This is what they call a gene-centric view; and it's a bit antiquated, if not misguided. Also, unless I've misread your remark, you seem to be equating genes with traits. It's actually not at all that linear of a pathway.


originally posted by: Barcs
Gradualism makes too much sense.

As a matter of surviving sudden changes to an environment? I don't see how gradualism is even still a real consideration.



posted on Feb, 29 2016 @ 08:38 PM
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originally posted by: PhotonEffect
How "massive" of a role would you say?


I'm not quite sure how to place the level in which genes can have in evolution on a specific scale.

Evolution requires a number of mechanisms, many of which require the some of the other mechanisms in order to produce the results we see.

Mechanisms like Natural selection, Genetic Drift, Gene Flow, Mutations, and so forth.


originally posted by: PhotonEffect
And without trying to put words in your mouth, are you suggesting that traits are solely the result of 'mutations' being expressed (as you put it)?


Could you rephrase that? Are you referring to the onset of traits or what makes a trait visible, or something else?


originally posted by: PhotonEffect
Why should this be put forth only in terms of genetic mutation?


It isn't only in terms of genetic mutation, you simply inquired about it, so that's why I used them in the example.


originally posted by: PhotonEffect
Don't beneficial traits derive from other ways?


Yes, absolutely. The mechanisms I listed previously in this post can greatly affect which traits are selected/produced



originally posted by: Ghost147
Do you believe that genes are selfish?


In many instances, yes. But it certainly is not the rule. It can be argued that the unit of selection could possibly be the phenotype, not the genotype, because it is phenotypes that interact with the environment at the natural-selection interface, at least in some instances.

The theory of evolution is far from a finite model. We're making discoveries all the time that help us produce a more accurate definition on how specific mechanisms function, and other discoveries that help us further understand previously unknown biological/genetic phenomena.



posted on Feb, 29 2016 @ 10:20 PM
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a reply to: Ghost147

I'm very fascinated by the Baldwin Effect

I have been for years.

I don't think that its all that controversial.

Your personal thoughts?

Kev
edit on 29-2-2016 by KellyPrettyBear because: (no reason given)



posted on Feb, 29 2016 @ 11:05 PM
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originally posted by: KellyPrettyBear
a reply to: Ghost147

I'm very fascinated by the Baldwin Effect

I have been for years.

I don't think that its all that controversial.

Your personal thoughts?


I think it's a very interesting theory, and it could certainly explain a few biological mysteries. No, I don't find it controversial at all. However, it's still highly theoretical, as it's very difficult to test.

Not only that, but many of the models that have reviewed the Baldwin Effect have had conflicting results.

Here's a paragraph from a very interest article that looks through some of these conflicting models:

So far, we did not consider feedback from the phenotype into its environment. That such feedback exists is postulated within the perspective of niche construction (Day et al. 2003; Laland and Sterelny 2006). Learning may play a role in the choice of environment and in the way the phenotype modifies its local environment (Laland and Sterelny 2006). If so, there is a feedback from the phenotype that would introduce an ever-changing fitness function, unlike that assumed under the Baldwin effect. Thus, there is a need to extend current theory on the Baldwin effect to include niche construction and evolution in non-constant environments in general.

So again, I believe the Baldwin Effect is highly likely to exist, but it still needs quite a bit of reevaluation and study.



posted on Feb, 29 2016 @ 11:10 PM
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a reply to: Ghost147

Fair enough.

But phenotypic feedback loops into any of the following:

Sexual selection
Social status enhancement
Modification of the local environment

Or any other "learning tricks which are
Transmittable" into enhanced fitness..

Is utterly fascinating to me...

Its almost sociobioligical Epigenetics.

Kev



posted on Feb, 29 2016 @ 11:45 PM
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a reply to: KellyPrettyBear

Indeed

I once watched a documentary where a mother orca had devised a way to have seals come to her for food, much like the same way the North American aboriginals had designed their fish traps where they would funnel them into an enclosed area and block the exit.

The mother orca was visibly shown to be teaching the strategy to her young too. I could definitely see Baldwins Effect taking play on that circumstance, but much more effectively at a population based scale with a sudden change to an environment



posted on Mar, 2 2016 @ 02:49 PM
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originally posted by: Ghost147
I'm not quite sure how to place the level in which genes can have in evolution on a specific scale.
Evolution requires a number of mechanisms, many of which require the some of the other mechanisms in order to produce the results we see.

Mechanisms like Natural selection, Genetic Drift, Gene Flow, Mutations, and so forth

Gotcha, so perhaps "massive role" was a bit of an overstatement.

How does one tell the difference between populations that have evolved by genetic drift vs ones by natural selection? And how would one determine the size of a population as being small or large, so the effects of genetic drift can be determined? How much of this is just guesswork?

Do genome wide studies reveal the differences?


originally posted by: Ghost147
Could you rephrase that? Are you referring to the onset of traits or what makes a trait visible, or something else?

I'm talking about gene expression, and the resultant traits. You seemed to single out traits as a result of mutation. I guess I'm not clear how that could be determined with any consistent degree of certainty.


originally posted by: Ghost147
It isn't only in terms of genetic mutation, you simply inquired about it, so that's why I used them in the example.

Right, although I don't believe I mentioned anything about mutations. I simply asked about genes


originally posted by: Ghost147
Yes, absolutely. The mechanisms I listed previously in this post can greatly affect which traits are selected/produced

I'm sorry, but which mechanisms specifically from the ones you mentioned actually "produce" traits?


originally posted by: Ghost147
It can be argued that the unit of selection could possibly be the phenotype, not the genotype, because it is phenotypes that interact with the environment at the natural-selection interface, at least in some instances.

But of course the phenotype is what's being selected, right? Do you not think so?

How can a genotype be selected when we know that very rarely does a gene act in isolation in relation to the trait[s] it influences. Most often genes are engaging epistatically, in networks, to influence the expression of a trait or multiple traits at once. Genes get hitchhiked. How can anyone know for certain what gene is getting selected for and why?



originally posted by: Ghost147
The theory of evolution is far from a finite model. We're making discoveries all the time that help us produce a more accurate definition on how specific mechanisms function, and other discoveries that help us further understand previously unknown biological/genetic phenomena.

I wish more folks around here would realize just how much we don't know before they start trying to "teach" others about evolution.



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