Biology Forum Evolution Mutations

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    • #8081
      supersport
      Participant

      Can anyone show me an example of a mutation that can either create a new structure or add a beneficial, selectable modification to an existing structure? I realize mutations can create duplications of already-existing structures and I know mutations can kill and/or deform organisms, but I’m looking for any actual scientific evidence that mutations can perform as advertised….I’m looking for evidence that mutations can create a beneficial modification to a physical structure.

      ToE says centipedes evolved from worms. Centipedes have 100 legs, while worms have no legs. So can someone give me a synopsis as to how the legs formed? Did the legs all form at the same time from one mutation in one lucky organism?…or did the legs form slowly over time by way of multiple mutations?

    • #75158
      mith
      Participant

      If you study the development of centipedes you might find out that all the segments are related so if legs evolve on one segment, it’s more than likely the other segments will also have legs.

      http://www.salk.edu/labs/mnl-t/clh/pede2.html

    • #75176
      TheHomeWorkKid
      Participant

      I have a related question. Is it possible in principle for a vertebrate to develop a functional set of extra limbs? Like, a bird with an extra pair of wings? I realize nothing like this has ever actually happened, or if it has there apparently isn’t a fossil record of it, but is there any concrete reason that couldn’t happen?

    • #75184
      kotoreru
      Participant

      Hmm well it’s not quite the same but search Google for the dolphin that has pelvic flippers.

      There are also quite a few cases of children born with an extra arm or two, so yes it is possible.

    • #75193
      Darby
      Participant

      On the worm / centipede front, research onycophorans.

      Just because worms don’t have legs, it doesn’t mean they don’t have appendages. Look at polychaete annelids.

    • #75205
      mith
      Participant

      @homeworkkid

      Look up hox genes and what they’ve done with fruit flies.

    • #75266
      supersport
      Participant
      quote mith:

      @homeworkkid

      Look up hox genes and what they’ve done with fruit flies.

      I don’t believe any of those mutations created anything that would be considered an upgrade or a beneficial, selectable modification. There are duplications, but as far as I’ve seen nothing that would qualify as something that would be selected for because of a benefit given to the organism. Also, legs have appeared sticking out of the head of a fly, but I’m not sure that would be too helpful either.

    • #75276
      mith
      Participant

      The question was "Can an organism develop an extra pair of functional limbs?" and the answer is yes, but depending on how the mutation happened your limbs might not be in the spots you want.

      But what you want to know is about an example of an adaptation of a functional component that is also beneficial? Well lookup the panda’s thumb. Dr Gould had a whole book dedicated to that subject.

    • #75289
      supersport
      Participant
      quote mith:

      The question was “Can an organism develop an extra pair of functional limbs?” and the answer is yes, but depending on how the mutation happened your limbs might not be in the spots you want.

      But what you want to know is about an example of an adaptation of a functional component that is also beneficial? Well lookup the panda’s thumb. Dr Gould had a whole book dedicated to that subject.

      how do you know that was a mutation? I’m asking for scientific verification that a mutation can create a new, functional body part or a new, beneficial modification to an existing body part. Simply observing one population of animals without thumbs and another population with thumbs does not qualify as scientific verification of anything.

    • #75292
      mith
      Participant

      How can you tell that it’s a mutation? Morphology.

    • #75294
      Darby
      Participant

      The genes for related but different physical structures are themselves related but different, but the timeframe means that we aren’t seeing the actual transitions, we’re reconstructing them.

    • #75318
      david23
      Participant

      or you can always do DNA comparison between worms centipedes and whatever and get a phylogenic tree to show who originated from who. There are a lot of premade models of mutation, gene drift and all the other evolution causing agents. You basically then compare your data to them.

    • #75327
      supersport
      Participant
      quote mith:

      How can you tell that it’s a mutation? Morphology.

      no you can’t. The same genes are used across the spectrum of nature to construct different animals. Scientists can tell no more by looking at genes than they can by looking at phenotype. Humans share 90-something percent of genes with mice, for example.

    • #75328
      supersport
      Participant
      quote david23:

      or you can always do DNA comparison between worms centipedes and whatever and get a phylogenic tree to show who originated from who. There are a lot of premade models of mutation, gene drift and all the other evolution causing agents. You basically then compare your data to them.

      that is not scientific validation. Likewise I could look at the molecular composition of salt and compare it to potassium….the fact that they are different in no way suggests that one evovled from the other — or that it’s even possible. I’m looking for scientific validation that mutations can create beneficial phenotypic effects.

    • #75329
      mith
      Participant
      quote supersport:

      quote mith:

      How can you tell that it’s a mutation? Morphology.

      no you can’t. The same genes are used across the spectrum of nature to construct different animals. Scientists can tell no more by looking at genes than they can by looking at phenotype. Humans share 90-something percent of genes with mice, for example.

      Right, so we examine a panda’s paw. At the place where there is supposed to be a wrist bone we find an enlarged bone that functions as a thumb. What conclusions can we draw?

    • #75347
      supersport
      Participant

      where’s the validation that the thumb got there by way of mutation? How can you be so sure this animal wasn’t just created this way or that the thumb got there by way of an epigenetic phenomenon?

    • #75348
      mith
      Participant

      What do you mean by just created that way? Are you proposing that pandas are created and unrelated to anything else genetically?

    • #75354
      supersport
      Participant
      quote mith:

      What do you mean by just created that way? Are you proposing that pandas are created and unrelated to anything else genetically?

      I mean created by the Creator.

      Are you asking if I think pandas descended from something other than a panda? I don’t know the answer to that for sure. It’s hard to say if all bears branched out from one "kind" of bear or if God made multiple "kinds" of bears. Unfortunately the Bible doesn’t specify.

    • #75355
      mith
      Participant

      http://www.talkorigins.org/faqs/comdesc/

      Come back with specific questions when you’ve finished reading up on how phylogenetics, radiocarbon dating and evolution works. Otherwise we’ll be talking in different languages.

    • #75357
      supersport
      Participant
      quote mith:

      http://www.talkorigins.org/faqs/comdesc/

      Come back with specific questions when you’ve finished reading up on how phylogenetics, radiocarbon dating and evolution works. Otherwise we’ll be talking in different languages.

      Oh, I’m quite aware of how evolution works….which is why I know that mutations do not help the cause of ToE. You can have a fancy theory, but if the evidence (ie..validation of mechanism) doesn’t support it, then it must be scrapped.

      Let me ask you…do you believe it would be a contradiction to ToE (or do you believe it’s even possible) for traits acquired during the lifetime of an animal due to a response to the environment to be inherited?

    • #75360
      AstusAleator
      Participant

      How about this: Rather than turning this into another creation/evolution "debate" why don’t we just continue to address the original topic? It’s an interesting question, and one I’d like to see explored more.

    • #75362
      mith
      Participant
      quote :

      that is not scientific validation. Likewise I could look at the molecular composition of salt and compare it to potassium….the fact that they are different in no way suggests that one evovled from the other — or that it’s even possible. I’m looking for scientific validation that mutations can create beneficial phenotypic effects.

      It’s a poor analogy because no one claims that potassium and chlorine are the "parents" of salt. But composition-wise you’d have to agree that one is created from components of the other. Somehow somewhere potassium and chlorine have to be involved to make KCl.

      And to me it seems more like you don’t quite understand how relatedness is compared. You say that mice and men have 90% in common. I’m not sure if the number is accurate but for the sake of argument lets say it is. But because there are only 4 bases , if you have two unrelated sequences you still get 25% similarity. So what does a 90% or 95% threshold of similarity mean? Is 90% really closely related or not?

      Plus you specified that the genes are 90% common. Some 95% of your DNA is non-coding. Are those differences going to be a factor?

      We’ve seen the hox gene being mutated to create whole legs in fruitflies, how hard would it be to enlarge a wrist bone? Granted the fruitfly is a lot more simpler, but why can’t the same mechanism be used to explain the panda’s thumb?

      Let’s say that epigenetics was at work here. What is the extent of its power? Do we have analogous cases ? If everything could be explained through epigenetics why do we have different DNA?

    • #75378
      alextemplet
      Participant
      quote supersport:

      Are you asking if I think pandas descended from something other than a panda? I don’t know the answer to that for sure. It’s hard to say if all bears branched out from one “kind” of bear or if God made multiple “kinds” of bears. Unfortunately the Bible doesn’t specify.

      The "kinds" argument has more holes in it than a sieve. First of all, how do you define "kind"? Is it a genus? A family? An order? No one has ever given a clear definition, and I suspect it is so that they can simply wait for proof of an evolutionary lineage to be proven, and then claim that it doesn’t matter because all the species involved are of the same "kind." I could just as easily claim that all vertebrates are the same "kind," and so it should be no problem to accept man’s common ancestry with apes. It’s a simple yet illogical fall-back argument that you can cling to even when your case has been disproven. I’m sorry, but in this forum we’ll need legitimate scientific theories, and scientific terminology, not vague references to "kinds."

      And since you mentioned the Bible, I would suggest you read it a little more carefully. I’ve read Genesis more times than I can remember and I am at a loss to figure out where it disagrees with modern scientific theory. In fact, the two are remarkably compatible.

    • #75380
      alextemplet
      Participant
      quote AstusAleator:

      How about this: Rather than turning this into another creation/evolution “debate” why don’t we just continue to address the original topic? It’s an interesting question, and one I’d like to see explored more.

      You know what, on second thought, you’re right. Perhaps we could start a thread in the off-topic to handle the debate that this has become?

    • #75386
      supersport
      Participant
      quote supersport:

      quote mith:

      Let me ask you…do you believe it would be a contradiction to ToE (or do you believe it’s even possible) for traits acquired during the lifetime of an animal due to a response to the environment to be inherited?

      I would like someone to answer this, please.

    • #75388
      supersport
      Participant
      quote alextemplet:

      quote supersport:

      Are you asking if I think pandas descended from something other than a panda? I don’t know the answer to that for sure. It’s hard to say if all bears branched out from one “kind” of bear or if God made multiple “kinds” of bears. Unfortunately the Bible doesn’t specify.

      The “kinds” argument has more holes in it than a sieve. First of all, how do you define “kind”? Is it a genus? A family? An order? No one has ever given a clear definition, and I suspect it is so that they can simply wait for proof of an evolutionary lineage to be proven, and then claim that it doesn’t matter because all the species involved are of the same “kind.” I could just as easily claim that all vertebrates are the same “kind,” and so it should be no problem to accept man’s common ancestry with apes. It’s a simple yet illogical fall-back argument that you can cling to even when your case has been disproven. I’m sorry, but in this forum we’ll need legitimate scientific theories, and scientific terminology, not vague references to “kinds.”

      And since you mentioned the Bible, I would suggest you read it a little more carefully. I’ve read Genesis more times than I can remember and I am at a loss to figure out where it disagrees with modern scientific theory. In fact, the two are remarkably compatible.

      yea, I agree, "kinds" is vague. However, likewise "species" is vague and hotly debated over its actual meaning. For example, is a grizzley bear a different "species" than a polar bear? Well most evolutionists say yes, however, these two bears can breed and produce a viable offspring….so what is the point in suggesting a speciation event if this is possible?

    • #75390
      mith
      Participant

      Are you saying it’s not meaningful to classify the polar bear and the grizzly as different simply because they can interbreed? I assure you, just because there are many definitions and some of them ill fitting does not mean they are useless.

      For example some fruitflies are categorized based on the tufts of hair on their middle legs which seems really bizarre but has uses for conservation purposes. Likewise the morphological definition might be used for telling between a wolf and a dog. There’s no use trying to see if a dog and a wolf would mate if you’re confronted in the Alaskan wild.

    • #75391
      alextemplet
      Participant
      quote supersport:

      yea, I agree, “kinds” is vague. However, likewise “species” is vague and hotly debated over its actual meaning. For example, is a grizzley bear a different “species” than a polar bear? Well most evolutionists say yes, however, these two bears can breed and produce a viable offspring….so what is the point in suggesting a speciation event if this is possible?

      I admit there is some debate over the exact definitions of scientific terms, but it is clearly understood that species are subgroups of genera, which are subgroups of families, which are subgroups of orders, etc. While there remains some difficulty with certain taxa as to which group or the other they should belong to, for the most part these taxanomical terms have very clear meanings. No one is going to hear "class" and think it means "family." What I ask you to do is tell me exactly which taxanomical level is equivalent to a "kind"; only then can we determine if your arguments have any scientific value or not.

    • #75409
      supersport
      Participant
      quote mith:

      Are you saying it’s not meaningful to classify the polar bear and the grizzly as different simply because they can interbreed? I assure you, just because there are many definitions and some of them ill fitting does not mean they are useless.

      .

      http://en.wikipedia.org/wiki/Species

      A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring

      so if a polar bear and a grizzly bear can breed and produce fertile offspring, why do evolutionists classify them as different species?

    • #75410
      alextemplet
      Participant
      quote supersport:

      http://en.wikipedia.org/wiki/Species

      A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring

      You need to take into account that Wikipedia can be edited by any retard with an internet connection. "Often" is the key word; that definition does not apply to all organisms. For example, it would be pointless and silly to try to categorize asexual species based on whether or not they can interbreed.

    • #75411
      supersport
      Participant
      quote alextemplet:

      quote supersport:

      http://en.wikipedia.org/wiki/Species

      A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring

      You need to take into account that Wikipedia can be edited by any retard with an internet connection. “Often” is the key word; that definition does not apply to all organisms. For example, it would be pointless and silly to try to categorize asexual species based on whether or not they can interbreed.

      http://trc.ucdavis.edu/biosci10v/bis10v … ncept.html

      In its simplest form, species means "kind." Natural selection can lead to speciation. Speciation can also occur as a result of other microevolutionary processes such as genetic drift and mutation.
      Attempting to determine whether different animals are the same species by appearance (phenotype) has been used extensively over the years, but may not reliable, due to the subtle variations that are displayed. Morphological traits may not always be useful in distinguishing species. Members of the same species may appear different because of environmental conditions. Morphology can vary with age and sex. Different species can appear identical.

      The biological species concept relies on reproduction to define relatedness of species. Ernst Mayer is credited with developing the official definition of a species: "Species are groups of interbreeding natural populations that are reproductively isolated from other such groups."

    • #75414
      alextemplet
      Participant
      quote supersport:

      http://trc.ucdavis.edu/biosci10v/bis10v/week7/speciesconcept.html

      In its simplest form, species means "kind." Natural selection can lead to speciation. Speciation can also occur as a result of other microevolutionary processes such as genetic drift and mutation.
      Attempting to determine whether different animals are the same species by appearance (phenotype) has been used extensively over the years, but may not reliable, due to the subtle variations that are displayed. Morphological traits may not always be useful in distinguishing species. Members of the same species may appear different because of environmental conditions. Morphology can vary with age and sex. Different species can appear identical.

      The biological species concept relies on reproduction to define relatedness of species. Ernst Mayer is credited with developing the official definition of a species: "Species are groups of interbreeding natural populations that are reproductively isolated from other such groups."

      Had you read just one more paragraph, you would have found:

      As good as it is, this definition is troublesome for organisms that are non-sexually reproducing, for those known only from fossils, or when life histories have not been studied.

      As I said before, simple interbreeding is not the only way – nor is it a fully reliable way – to differentiate species.

    • #75416
      mith
      Participant

      I already read the species article, and if you scroll down you’ll see the nuances I discussed in my previous post.

    • #75420
      supersport
      Participant
      quote alextemplet:

      quote supersport:

      http://trc.ucdavis.edu/biosci10v/bis10v/week7/speciesconcept.html

      In its simplest form, species means "kind." Natural selection can lead to speciation. Speciation can also occur as a result of other microevolutionary processes such as genetic drift and mutation.
      Attempting to determine whether different animals are the same species by appearance (phenotype) has been used extensively over the years, but may not reliable, due to the subtle variations that are displayed. Morphological traits may not always be useful in distinguishing species. Members of the same species may appear different because of environmental conditions. Morphology can vary with age and sex. Different species can appear identical.

      The biological species concept relies on reproduction to define relatedness of species. Ernst Mayer is credited with developing the official definition of a species: "Species are groups of interbreeding natural populations that are reproductively isolated from other such groups."

      Had you read just one more paragraph, you would have found:

      As good as it is, this definition is troublesome for organisms that are non-sexually reproducing, for those known only from fossils, or when life histories have not been studied.

      As I said before, simple interbreeding is not the only way – nor is it a fully reliable way – to differentiate species.

      and as I said to start this off, the concept of "species" is just as vague as "kinds" is in the Bible.

    • #75421
      alextemplet
      Participant
      quote supersport:

      and as I said to start this off, the concept of “species” is just as vague as “kinds” is in the Bible.

      So are you implying that "kinds" equals "species"?

    • #75423
      AstusAleator
      Participant

      Oh please. The word ‘species’ is used by scientists specifically because its meaning is more refined and definable. "kind" can imply ANY relation.
      Scientific language is used with the specific intent to narrow down and winnow out extraeneous meanings and thus confusion. So IF YOU WOULD tell me what taxonomic level you are indicating when you say "kinds" and we can continue our SCIENTIFIC conversation from that point.

    • #75435
      supersport
      Participant
      quote AstusAleator:

      Oh please. The word ‘species’ is used by scientists specifically because its meaning is more refined and definable. “kind” can imply ANY relation.
      Scientific language is used with the specific intent to narrow down and winnow out extraeneous meanings and thus confusion. So IF YOU WOULD tell me what taxonomic level you are indicating when you say “kinds” and we can continue our SCIENTIFIC conversation from that point.

      then tell me…is a polar bear a different species than a grizzly bear — and why? Likewise are different "species" of Darwin’s finches actually different species? Why or why not.

    • #75436
      supersport
      Participant
      quote alextemplet:

      quote supersport:

      and as I said to start this off, the concept of “species” is just as vague as “kinds” is in the Bible.

      So are you implying that “kinds” equals “species”?

      no, I’m just saying they are both vague and ultimately undefinable with any real accuracy. The problem is evolutionists have a tendency to lable different finches, for example, as different "species" of finches, yet they can all breed and produce viable, fertile offspring. So if that is the case, on what basis is there to say they are different "species?"…just because they have a different beak shape? If that’s the case, then where do you draw the line?….do different colors dictate different species? How about size? Ultimately, it has to come down to whether or not one type of animal can breed with another similar animal and produce viable, fertile offspring….but the problem is, evolutionists will never verify a new case of speciation by checking to see if the two supposed newly-formed species can breed. They just simply close their eyes, make a guess, and hope no one will question their assertion of speciation.

      If you don’t believe me, please find me an example of speciation, as claimed by evolutionists, and then show me where they verify that the new species cannot breed with the mother species and create fertile offspring.

    • #75444
      alextemplet
      Participant

      http://www.talkorigins.org/faqs/faq-speciation.html

      Here’s a quote:

      quote :

      Over the last few decades the theoretically preeminent species definition has been the biological species concept (BSC). This concept defines a species as a reproductive community.

      The site goes on to list several observed cases of speciation, but I believe the species definition that it gives is perhaps the best one currently available. Basically, it is a population that reproduces. If we are to take the grizzly and polar bears as an example, they would be two separate species, since they do not breed with each other in the wild; they are thus two separately reproducing groups. The same could apply to Darwin’s finches.

      Now could you please tell me which taxanomic level is meant by "kind"?

    • #75457
      supersport
      Participant
      quote alextemplet:

      http://www.talkorigins.org/faqs/faq-speciation.html

      Here’s a quote:

      quote :

      Over the last few decades the theoretically preeminent species definition has been the biological species concept (BSC). This concept defines a species as a reproductive community.

      The site goes on to list several observed cases of speciation, but I believe the species definition that it gives is perhaps the best one currently available. Basically, it is a population that reproduces. If we are to take the grizzly and polar bears as an example, they would be two separate species, since they do not breed with each other in the wild; they are thus two separately reproducing groups. The same could apply to Darwin’s finches.

      Now could you please tell me which taxanomic level is meant by “kind”?

      you are simply validating my point. You are proclaiming that these species don’t interbreed in the wild — but do they really?

      http://news.nationalgeographic.com/news … photo.html

      And finches are not different species because a single finch can alter its beak shape during development and emerge with a completely different shape/size than his parents did by way of a re-expression of genes. So what’s the logic in saying the offspring is a different species than the parent?

    • #75466
      alextemplet
      Participant
      quote supersport:

      you are simply validating my point. You are proclaiming that these species don’t interbreed in the wild — but do they really?

      Perhaps in a few rare cases they might, but for the most part they do not.

      quote supersport:

      And finches are not different species because a single finch can alter its beak shape during development and emerge with a completely different shape/size than his parents did by way of a re-expression of genes. So what’s the logic in saying the offspring is a different species than the parent?

      I’m sure if you turned off a few human genes and re-expressed others, a human embryo could develop into a chimpanzee, and yet both are different species. But that sort of thing doesn’t happen naturally.

    • #75474
      AstusAleator
      Participant

      Ok sport, you are setting up a straw man here. There are different ways to define species because there are different forms of life. As was pointed out earlier, you wouldn’t want to define an asexual species by what it can or can’t reproduce with.
      You have to take a larger ecological look at the populations in question. Each individual species should have its own unique ecological footprint.
      By now you’ve probably looked through all the different species concepts and know that "viable offspring" is not the only way to define a species.

      So you say it’s vague and subjective, because the rules set down to define species don’t always work in every scenario.

      The key is that there ARE rules though, and they can be very detailed. To declare a species, a scientist must undergo rigorous taxonomic definition and then be subjected to peer review.

      Do you really think that science (specifically biology and ecology) would have been able to accomlish what it has if we did no more than identify "kinds" of organisms?

      I can see it now, the doctor has a patient with a severe infection so he grabs a piece of bread with mold on it and smears it all over the infected area and makes the patient eat the rest. "Hey it’s the fuzzy kind of mold, don’t worry!"

      No sir, "kind" is a cop-out because you’re unwilling to aquiesce to the validity of taxonomy, BECAUSE, taxonomy is *gasp* based (at least in part) on evolutionary theory.
      I’m not saying it’s perfect (ie polar bears and grizzlies, dogs and wolves), but it’s valid. It’s a system that is capable of correcting itself.

      Go ahead, test it. Do an internet search for "Rhinichthys osculus".
      Now do a search for "little fish" or "minnows" or "spotted minnows" or "little spotted fish"
      Heck do a search for "things that swim"
      Those are all "kinds"…

      I’m not sure what you’re trying to prove by claiming the word "kind" is on par with taxonomic nomenclature, or other valid systems.

      Really I’m at a loss as to what your point is with the whole "kinds" thing.

      Oh and with the grizzlies, etc. So it’s vague as to where the species line is going to be drawn… so what? If they’re declared the same species (which i think they are) they will still be given different subspecific eptithets. They will be differentiated in their names, as they should be, because they typically live in very different ecosystems and have very different lifestyles.
      I believe how I learned it was that Polars are Ursus arctos arctos and Grizzlies are Ursus arctos horriblis. The point is that no scientist is going to call them the same exact animal.

    • #76182
      extinct
      Participant
      quote supersport:

      Can anyone show me an example of a mutation that can either create a new structure or add a beneficial, selectable modification to an existing structure?

      big breasts

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