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Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
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Author | Topic: "Macro" vs "Micro" genetic "kind" mechanism? | ||||||||||||||||||||||||||||
RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
In Message 183 states:
Yes--the documented changes of coloration of peppered moths is an example of natural selection. But does this prove evolution? Natural selection is the premise of the survival-of-the-fittest--organisms that exhibit traits more ideal for their environment will out-survive organisms without these traits and reproduce, ie dark-colored moths survive near the factories because light-colored moths stand out on the bark of dark-colored trees and are more easily seen by predators, while the dark-colored moths are hidden better. Thus the population is dominantly darker colored after several generations of moths reproducing since the lighter ones are being eaten! Anyway, natural selection can and does cause such variation in the natural world that can give rise to new species and even new genus. This has been observed and well, I know it used to be called microevolution, though I have heard that term is somewhat out of date. But natural selection cannot account for macroevolution, ie taking a one-celled organism and evolving it into a vertebrate through many transitional forms, because microevolution deals with only with genes that are already in place! Macroevolution requires the addition of new genes! These peppered moths will always be peppered moths, no matter how much they mutate. They will need an entirely new genome to become something else. Thus, natural selection is proven scientific fact... but the theory of evolution is not. Rather that take the {Peppered Moth} thread off topic to discuss the majority of this post, I have moved my response to this thread for further debate as necessary. Quotes below are selected from the above quoted post.
Anyway, natural selection can and does cause such variation in the natural world that can give rise to new species and even new genus. This has been observed and well, I know it used to be called microevolution, though I have heard that term is somewhat out of date. Actually natural selection does not cause the variation, it only selects among the available variations those traits that get born into the next generation. This is both a question of survival and reproduction, as an individual can survive and not reproduce, or one can reproduce and then die. The variation comes from shuffling the gene deck -- by sex and by mutations. Sex shuffles which genes are passed to the offspring with the typical Mendelian possibilities for things like blue eyes and blond hair, and mutation makes those different variations possible. Many will be lethal (2/3rds of human zygots never make it to become fetuses for instance) or prevent fertilization (basic incompatability -- and may occur in hybrid populations, as in mules), but there will also be some that are neutral (have no apparent effect under then current selection conditions), and the occasional one will have some benefit such that either reproduction or survival will be enhanced (under then current selection conditions). Some mutations will be only slightly deleterious, or only deleterious in double doses (from both parents) and these mutations will also tend to survive within the species populations. The end result of mutation and natural selection is speciation -- an observed fact, both in experiments in labs and in wild populations -- where two or more populations become reproductively isolated for a number of different reasons and diverge due to the accumulation of change over time. Yes this has been called "microevolution" by both creationists and by some evolution biologists. The creationists have been backed into "microevolution" being speciation by the undeniable evidence that this actually occurs (they previously argued that speciation was the "macroevolution" that couldn't occur), and the evolutionary biologists that use the terms use them to differentiate between the slightly different population dynamics that occur before speciation as compared to after speciation.
But natural selection cannot account for macroevolution, ie taking a one-celled organism and evolving it into a vertebrate through many transitional forms, because microevolution deals with only with genes that are already in place! Macroevolution requires the addition of new genes! Funny how you think "microevoloution" could be {antiquated\archaic\obsolete}, but you have no qualms about asserting your opinion on "macroevolution" ... Mutation is the process that adds new genes into the mix, it is the source of the ones "already in place" for "microevolution" -- although technically you are mixing "micorevolution" with natural selection there eh? Mutation provides variety, natural selection weeds out deleterious new genes, is indifferent to neutral new genes, and boosts beneficial new genes. The difference between "microevolution" and "macroevolution" is not in how much evolution occurs in a generation, but how many generations are involved for the change to be significant enough to human observers to classify into different categories (taxonomy classifications are a purely artificial human intellectual construction): classification by species and ancestry is all that is really needed (and for an individual organism the necessary classifications are even simpler: is it mate material, food, predator, or environment?). Before speciation occurs there is a re-mixing of genes within the species population with each generation, so that beneficial, neutral, and some (not too lethal) deleterious (see sickle cell anemia) mutations are continually mixed and remixed within the gene pool for the species population. Some old variations are sometimes lost through sexual selection and genetic drift, and some new variations from mutations get spread throughout major portions of the population before they appear to have any effect. Over time this results in gradual change in the species population, and sometimes those changes are 'significant' (to the human observer) enough that they get classified as a new species -- although at no time is there reproductive incompatability within the population and there is no way to verify whether reproductive isolation would be valid if populations of current and ancestral species were somehow able to bridge the time barrier to breed. This is still "microevolution" within each generation: mutation and natural selection causing change in species over time. Once speciation occurs the population dynamics change. Once speciation occurs there is no re-mix of the genetic material within the total population but only within each 'daughter' populations. The 'daughter' populations are now free to diverge genetically as much or as little as mutation and natural selection allow -- there is no mechanism to constrain them ... other than the limitations of what is provided by mutation and what is passed to the next generations by natural selection.
These peppered moths will always be peppered moths, no matter how much they mutate. They will need an entirely new genome to become something else. Even with a new genome they will still be peppered moths, just as dogs will always be dogs, and apes will always be apes, etcetera. This is the structure of the family tree -- that all subsequent species will still be children of ancestral species, in the same way that your children will always be the progeny of your parents and their parents. But dogs will always also be canines, but they will never be foxes (who will also always be foxes and always be canines but never dogs) or coyotes (who will also always be coyotes and always be canines but never dogs or foxes). When there was only one species of canid there were variations in the species population but there were only canids ... and then speciation occurred with the results that there are now dogs, wolves, foxes and coyotes. Or look at horses, donkeys, zebras and onagers. They will always be equines ... that is the nature of descent from common ancestor populations. If the two varieties of peppered moths became reproductively isolated so that they became different species they would still both be peppered moths, but you would have one species of light peppered moths and one species of dark peppered moths. Then over time each species would develop different varieties within their species populations. So far this has not happened. They are still considered one species. As such the evidence of their population shifts -- from predominantly light with some dark, to predominantly dark with some light, and then back to predominantly light with some dark -- is clearly a result of preferential predation as a selection mechanism with the change being due to altered environment that change the relative fitness of the different varieties for blending into the predominant environment. And until speciation occurs this will only be evidence of natural selection in action. Enjoy. we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
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tuned2g Inactive Member |
Hey, thanks for pointing out several flaws in my terminology and logic. I do agree with everything you said (natural selection does not cause variation, but selects... etc.) Sorry about getting a little off topic in the peppered moths thread. I will work on maintaining focus and logic in my future posts. The main point I am trying to make is microevolution cannot produce macroevolutionary changes. I would love to see some documentation stating the contrary, but I have yet to. Please, if I am ignorant or confused, go ahead and give me something I can ponder over.
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Dr Adequate Member (Idle past 313 days) Posts: 16113 Joined: |
We know Darwin in the first edition of "Origin" offered one lonely example of his theory: bears becoming acquatic and given enough time could somehow morph into a whale-like creature. This is untrue. Remember that many people reading this thread have read the Origin of Species, so we know you're talking nonsense. You're not reciting this falsehood to a bunch of ignorant creationists whom you can fool; you're reciting it in the company of educated people who are just going to laugh at you. What do you hope to achieve by this? Edited by Dr Adequate, : No reason given.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Hey, thanks for pointing out several flaws in my terminology ... Sorry about getting a little off topic in the peppered moths thread. Not a problem. That's typical for everyone when they first post. You can also learn some 'trick' (like quote boxes) by using the {peek mode} button at the top right corner of the "Text of message you're replying to:" window, and seeing how others format their posts.
The main point I am trying to make is microevolution cannot produce macroevolutionary changes. I would love to see some documentation stating the contrary, but I have yet to. At least you are on the right track with "macro"evolution being a product of "micro"evolution. Many cycles of "micro"evolution. The question back to you is what could prevent it from happening? To really understand this we need to look at what a "macroevolutionary change" involves. Note that part of the question involves what we as humans consider remarkable, versus what is just another {difference between species} in the real world: why do we classify animals the way we do? Enjoy. we are limited in our ability to understand by our ability to understand RebelAAmericanOZen[Deist
... to learn ... to think ... to live ... to laugh ... to share.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
In Message 26, seekingfirstthekingdom says:
still stand by my comments that the overwhelming evidence in the fossil record points to kinds staying within genetic boundaries instituted by our creator in genesis. Seeing as that is a Great Debate thread, I thought I would move my response, Message 33,here to let any other people reply to it:
quote: And in Message 41 of that thread:
quote: The response was tepid ... (Message 46 and Message 51):
im going to research this.anymore proof apart from a chart that what you say here: ... is actually true or you just defending a belief system?
i will research the orca shark thing tho but i suspect its just another atheist red herring. with my response in Message 56:
quote: That is, of course, according to classical taxonomy, which was originally developed by Linnaeus to sort out living forms into "kinds" ... What we have is the evidence of convergent evolution to show that there is no barrier to what an organism can evolve into. A bat
A bird
A pterosaur
Three different evolutionary paths to the same end. Either they are the same "kind" or there is no genetic barrier to the evolutionary convergence between different "kinds" of organisms. These are just a few of the many examples of convergent evolution. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • • |
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AlphaOmegakid Member (Idle past 2904 days) Posts: 564 From: The city of God Joined: |
Hey RAZD,
I've been away for awhile. Looks like this thread needs me. A real live creationist. And with answers to your questions....
razd writes: The whole system was supposedly set up during those original 6 days, so there must be a mechanism in place that prevents "macro"evolution ... what is the built-in biological mechanism that prevents this from happening? Where is it located? Why hasn't it been found? The "mechanisms" that you are looking for are in all living organisms, and all of them have been discovered and are well documented. That is the answer to the last two questions. So what are the mechanisms that prevent or limit the evolution of different biblical "kinds" of animals... 1. Death by mutation2. Disease by mutation 3. Sex 4. Speciation 5. Protein folding - this may come under disease or death. 6. Genetic capacity There is a list of six biological mechanisms that are fully known to limit or prevent evolution beyond a certain levels. To assert that evolution via natural selection or genetic drift doesn't have any limits is just absurd. There are many limits that would have to be hurdled to make new genes. These hurdles limit evolution. PS. #6 is not well understood or defined, but it is written about much. A capacity is a limit. Edited by AlphaOmegakid, : No reason given.
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Blue Jay Member (Idle past 2726 days) Posts: 2843 From: You couldn't pronounce it with your mouthparts Joined: |
The Kid!
Welcome back, man!
AlphaOmegakid writes: 1. Death by mutation2. Disease by mutation But, not all mutations lead to death or disease. I just read a paper called "A case study of evolutionary computation of biochemical adaptation" (links to the abstract: I'm not sure if the full text is freely available to the public): it's an interesting article about a mathematical simulation (which I don't even pretend to understand) that supports the plausability of transitional fitness. Here's a snippit of the abstract:
quote: Or, in other words, mutation and natural selection can drive a gradual sequence of character states, each one of which is "fit," towards an optimum within a reasonable time frame. They also seem to imply that the end-state is predictable, and ScienceDaily latches on to that concept. I'd be interested in your comments on this research. -----
AlphaOmegakid writes: 3. Sex Do you mean, by this, that sex prevents two species from interbreeding? How does this stop one kind from turning into two kinds, though, especially when both daughter kinds use reproductive parts that are still physically compatible with the opposite parts of the parent kind? -----
AlphaOmegakid writes: 4. Speciation I don't know what you mean by this. Speciation prevents the emergence of new kinds? -----
AOkid writes: 5. Protein folding - this may come under disease or death. I'd like to hear a bit more about this. I remember you having discussed it before, and it came up in an undergrad review I did about bears, but I don't know a great deal about it yet. What problem do you think this causes for trans-baraminal evolution? -----
AOkid writes: 6. Genetic capacity I think "genetic capacity" is almost total nonsense (even though I'm not in a position to make a ruling on genetics). However, I am fully willing to be convinced otherwise with solid evidence. Edited by Bluejay, : Two-word addition. Edited by Bluejay, : "Also" and "too" are redundant. Edited by Bluejay, : Rewording (undid first two edits in the process) Edited by Bluejay, : I needed an even number of edits. -Bluejay/Mantis/Thylacosmilus Darwin loves you.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Hi AlphaOmegakid, been a while.
The "mechanisms" that you are looking for are in all living organisms, and all of them have been discovered and are well documented. That is the answer to the last two questions. Just to be clear you are claiming that this list encompasses all the processes that prevent evolution from wandering too far afield and ending up like some other kind of animal.
So what are the mechanisms that prevent or limit the evolution of different biblical "kinds" of animals... 1. Death by mutation2. Disease by mutation 3. Sex 4. Speciation 5. Protein folding - this may come under disease or death. 6. Genetic capacity Should be easy to deal with. Let's start with the stipulation that we are talking about limiting one form of life from being similar to another, that we are NOT talking about identical reproduction of another life form. Why? Because evolution does not say that identical forms occur from different lineages of organisms, rather the opposite: organisms will diverge to take advantage of the opportunities of their ecology/ies.
1. Death by mutation Interestingly, death by mutation occurs when a mutation is deleterious, removing the deleterious mutation from the genetic pool of the population. Amazingly the death of some organisms in a population does not prevent the rest of the population from evolving - changing hereditary traits in populations from generation to generation - as such quickly removed mutations don't last long enough to impact the population. Death does not occur with neutral or beneficial mutations, nor does it limit the occurance of these types of mutations in other members of the population. Mutations that allow an organism to take advantage of a different ecology/ies, gives them more options, not death. So I don't see how "death by mutation" necessarily limits the rest of the population in the slightest, in how they can evolve to take advantage of their ecological opportunities.
2. Disease by mutation This is just a lesser deleterious version of (1) above, and curiously this can have more impact on a population than death ... if the organisms that are diseased reproduce and pass on their mutation, or if they interfere with the mating of others (think of women married to sterile men). The fascinating part though, is that mutations that may be deleterious in one ecology can be beneficial in another, and so what is "sick" in one ecology may be "pre-adapted" for a different ecology, thus diversifying life as it spreads into new systems. Stout fins may be less adapted to swimming in the open ocean, but have an advantage to pushing around on muddy bottoms and for crawling out onto land. So I don't see how "disease by mutation" necessarily limits the rest of the population in the slightest in how they can evolve to take advantage of their ecological opportunities.
3. Sex Humorously, sex is how genetic traits are passed from one generation to the next. The organisms that are better at it have more offspring. Surely you've noticed that sex results in progeny? Isn't that what the big deal about birth control and abortion is about? Interestingly it is sex that mixes traits in different combinations, each organism being composed of many hereditary traits with different levels of advantages and disadvantages for survival and breeding, and sex allows these to occur in different mixes\combinations. Again, this results in increased diversity in a population, not in a limitation. So I don't see how "sex" necessarily limits the population in the slightest in how they can evolve to take advantage of their ecological opportunities.
4. Speciation Fascinatingly speciation is just the point where evolution isolated two populations formerly sharing hereditary traits into two or more populations developing new traits to adapt to different ecologies, so that after speciation they become more different. Speciation adds diversity to life, not limiting it. So I don't see how "speciation" necessarily limits the daughter populations in the slightest in how they can evolve to take advantage of multiple ecological opportunities.
5. Protein folding - this may come under disease or death. Yes, it would be one of the mutations that causes death of the fetal organism. As in (1) above this would have very little effect on the population. So you are down to 5 processes, with only one more to go to actually show some way of limiting evolution ...
6. Genetic capacity Curiously, when I use google scholar to find discussions of "genetic capacity" I get a series of articles about the ability of organisms to diversify into new and different ecologies, not prevent them from changing. So I don't see how "genetic capacity" necessarily limits a population in the slightest in how it can evolve to take advantage of their ecological opportunities.
There is a list of six biological mechanisms that are fully known to limit or prevent evolution beyond a certain levels. And amazingly all of them fail to demonstrate a mechanism that prevents evolution from occurring, continuing to take advantage of ecological opportunities to diversify and spread. The problem is that you did not show how they result in preventing evolution beyond any kind of level. Assertion is not evidence.
A capacity is a limit. So the capacity to add is a limit. Interesting. Presumably this is how you prevent mutations from adding up ... oh wait that would be the inability to add, not the capacity. Now look at these little fellas:
Flying Squirrel (on left):
quote: Rodentia includes mice, rats, squirrels, chipmunks, gophers, porcupines, beavers, hamsters, gerbils, guinea pigs, degus, chinchillas, prairie dogs, groundhogs, and others.
Sugar Glider (on right):
quote: Diprotodontia includes kangaroos, wallabies, possums, koala, wombats, and many others. How is it that these two species, evolving from quite different backgrounds, with many diverse relative of other kinds of animals in between them and a common ancestral pool, have come to evolve to be such similar kinds of organisms? I look forward to your presenting evidence of the process that prevented this from occurring. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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Coyote Member (Idle past 2134 days) Posts: 6117 Joined: |
Now that was a good post.
Given your post, we are still looking to find some mechanism that prevents the micros from becoming macros. I have been asking creationists to provide that mechanism for several years and have never received a suitable answer either. Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.
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olivortex Member (Idle past 4806 days) Posts: 70 From: versailles, france Joined: |
Well, i must say i did not even kow about such resembling animals! they're too cute.
But my favourite animals are still the CAT and the RED PANDA, which is, undoubtedly, an interesting specie, actually not classified as an ursidae, like the GIANT PANDA, considered for a while as being part of the raccoon family. I know it has not much to do with the topic here, besides pointing towards the taxonomic problems, implying problems of reading and discussion among pure amateurs like me. Kingdom: AnimaliaPhylum: Chordata Subphylum: Vertebrata Class: Mammalia Order: Carnivora Suborder: Caniformia Family: Ailuridae Genus: Ailurus Species: Ailurus fulgens wow, i can't seem to be able to post images. i'm new on this. i know i'll soon be helped. Edited by olivortex, : No reason given.
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Annafan Member (Idle past 4607 days) Posts: 418 From: Belgium Joined: |
olivortex writes: wow, i can't seem to be able to post images. i'm new on this. i know i'll soon be helped. Use the "peek" button in the lower left corner of a post with images (or other features that look interesting) to check out the tags that you have to use to achieve the same effects.
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Annafan Member (Idle past 4607 days) Posts: 418 From: Belgium Joined: |
RAZD writes: 1. Death by mutation Interestingly, death by mutation occurs when a mutation is deleterious, removing the deleterious mutation from the genetic pool of the population. Amazingly the death of some organisms in a population does not prevent the rest of the population from evolving - changing hereditary traits in populations from generation to generation - as such quickly removed mutations don't last long enough to impact the population. Death does not occur with neutral or beneficial mutations, nor does it limit the occurance of these types of mutations in other members of the population. Mutations that allow an organism to take advantage of a different ecology/ies, gives them more options, not death. So I don't see how "death by mutation" necessarily limits the rest of the population in the slightest, in how they can evolve to take advantage of their ecological opportunities. One of the most important things to point out here, IMO, is the typical reproductive overcapacity of organisms: even in the absence of any deadly mutations and other causes of death, the available resources and environment would eventually limit how many organisms would stay alive. Darwin himself calculated how many elephants (very slow breading animals!) there would be if so many wouldn't die because of survival of the fittest: in a geological blink of an eye the whole solarsystem would be filled with elephant poop (that's not exactly his calculation, but it amounts to the same ! This insight was extremely important for Darwin to come up with his concept of natural selection, and he got it mainly by reading the work of Thomas Malthus, "An Essay on the Principle of Population" The reproductive overcapacity means that the impact of detrimental, deadly mutations is nearly meaningless. It's not much more than background noise.
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olivortex Member (Idle past 4806 days) Posts: 70 From: versailles, france Joined: |
mm. i must be dumb or not fully awaken. can't import any image from another page. i may find a way later. anyway it doesn't matter that much.
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Parasomnium Member Posts: 2224 Joined: |
You can read about it here (scroll down a bit).
Good luck.
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RAZD Member (Idle past 1433 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Hey olivortex,
... can't import any image from another page. For other formating tips see Posting Tips One should (a) be careful not to post copyright pictures, and (b) reference sites of origin etc. http://animals.nationalgeographic.com/...mals/red-panda.html
quote: Cute. WIth a Panda's Thumb. One wonders what "kind" they are. Enjoy. by our ability to understand Rebel American Zen Deist ... to learn ... to think ... to live ... to laugh ... to share. • • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •
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