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Junior Member (Idle past 3729 days) Posts: 13 From: mississippi Joined: |
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Author | Topic: If evolution is true, where did flying creatures come from? | |||||||||||||||||||||||||||||||||||||||||
RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Welcome to the fray Zatara,
Though there is disagreement among biologists, most agree birds evolved from dinosaurs. Archaeopteryx is the first good example of a "feathered dinosaur." It was discovered in 1861 ... We actually have a number of fossils besides Archy, and a new one has just been found in China:
The oldest record of ornithuromorpha from the early cretaceous of China (Nature Communications, Article number: 6987 doi:10.1038/ncomms7987 Published 05 May 2015)
quote: Lots of good stuff in the article, including images of the fossils of the feathers. Enjoy
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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined:
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Hi Faith, back at it again eh?
But what's so odd really, is that very noticeable changes occur within a few generations when you isolate a small number of a Species. Darwin demonstrated this with pigeons, getting extreme variations in a very short period of time just by breeding to enhance a chosen trait. ... Indeed, what you had was the joint effect of mutations and selection. His insight was that the selection process occurred naturally, where animals that survived and bred passed their genes (that enabled them to survive and be selected by mates for breeding) to the next generation. The ability to hop a little further because of the arrangement of feathers enabled the bearer more survival ability to catch or evade. Feathers could also be a means to attract mates as we see today, so selection for greater feathers by sexual selection led to the proliferation of feathers that then became an asset to hop and glide and finally to fly.
... All this demonstrates is the great variability that is built in to a Species, ... In know this is your pet theory, and you have presented it hundreds of time, and every time it gets refuted by evidence that shows new DNA in species that did not have it before. What is built in is a predilection for mutation that provides the variation that selection works on.
... that develops through microevolution if the breeding pool is isolated. Isolation can occur either artificially by human manipulation, or by natural factors such as migration of a small number of a Species in the wild. Either method will produce a new type or breed or race or variety. Correct -- isolation leads to different selection pressures on the different populations, as has been discussed with black pocket mice in the southwest. The same for the Peppered Moths -- different environment produces different selection processes that result in visible changes.
Change is built into the genome, ... Change is built into the susceptibility of DNA to mutate, during the creation of sex gametes or during the process of cell division during the development of an organism. The development can be affected by chemicals, hormones and temperature. An example of the is the Russian silver fox experiment where the foxes were selected for less aggressive behavior over several generations, and the offspring evolved to be more like dogs, with floppy ears, spots, and behavior changes relative to the parent population.
... but it can only vary the traits of the particular Species that are programmed into its genome, it can never produce something that is not already genetically available to that Species. This statement has been shown to be false time and again. That you keep repeating this fallacy does not begin to make it valid. Several bacteria studies show the appearance of DNA sequences that did not exist in the study population at the start.
... Oodles of time isn't going to make one Species into another ... If you mean turn a cat into a dog, then of course that isn't going to happen -- but that is not how (macro)evolution works, so that not happening just disproves a fallacy. If you mean that new species are not going to rise out of varieties and continued microevolutionary process in isolated populations, then you are wrong because the development of new species has been observed.
... This is macroevolution's ultimate downfall. ... Except that it isn't macroevolution, but creationist pseudomacroevolution that fails. Macroevolution in evolutionary biology is the process of speciation and the formation of nested hierarchies. You already understand the basic mechanics of this:
... Either method will produce a new type or breed or race or variety. ... which is the beginning of speciation (new species formation)and the formation of nested hierarchies. We see this process taken to the next level with the Asian greenish warblers (Phylloscopus trochiloides):
... where P.t.viridanus (blue) is almost completely isolated, but shares a small overlap interbreeding zone with P.t.ludlowi (green), which is almost completely isolated, but that also shares a small overlap interbreeding zone with P.t.troichilodes (yellow),which is almost completely isolated, but that also shares a small overlap interbreeding zone with P.t.obscuratus (orange),which is almost completely isolated, but that also shared a small overlap interbreeding zone with P.t.plumbeitarsus (red), but now we get to the interesting part ... P.t.viridanus (blue) and P.t.plumbeitarsus (red) share a small overlap zone but do not interbreed -- they are reproductively isolated, so variations in one population are not shared with the other population. This is how speciation -- the development of new species -- occurs, but normally the process happens over time instead of over distance.
... If the Species is genetically equipped for fur it isn't going to grow feathers no matter how clever you are at breeding strategies. ... Well, I think we can agree that this has not happened and is not likely to happen. But in my case, it would not be likely to happen because there would be no reason for it. What would be the selection pressure to change fur into feathers? Bats fly with fur instead of feathers, they took a different evolutionary path dictated by what they had available to be mutated and developed into wings. Bats don't need feathers to fly so there is no pressure for them to evolve. Flying squirrels and sugar gliders and Colugos and Wallace's frogs and flying fish and flying geckos and flying boa snakes have all taken different evolutionary paths dictated by what they had available to be mutated and developed into winglike surfaces -- whether those wing shapes were good enough for powered flying, or more often just sufficient to glide. Multitudes of insects have developed flight, some even evolve wings lose wings and then re-evolve wings. Insects don't need feathers to fly either, and would likely be encumbered if by some strange metamorphosis they did evolve feathers. Macroevolution of species is not metamorphosis of individuals. Small spiders fly by kiting a strand of web material, and drift with the wind in much the same way that multitudes of plant have flying seeds.
... OR, if you get something in the direction of feathers by assiduous selection, you will sacrifice so much else to the effort you may not even have a viable living creature at all in the end. That is, if you try to breed from an anomaly you will most often get disease and deformation. ... Agreed, artificial selection can -- and has -- resulted in organisms that would be less fit in the wild than their parent populations. Many dog varieties fall into this category, many with endemic problems that plague them.
... That is, Species are capable of change but there are limits. ... What are those limits? Where are those limits observed? Or is it like flipping a coin ... each flip of a coin can be heads or tails, but what it was in the last generation of flipping has no effect on what will happen with the current flip.
... Extreme change, ... What change is "extreme" Faith?
... even if produced by a series of small changes, ... At what point does continued small change become "extreme" -- what is your measure of difference?
... is more likely to lead to extinction than further ability to change. Each step in the process is an adaptation for better survival and reproduction in a changing world, and like the coin there is no reason for the future to be affected by the past, no chain that says "this far and no farther" that has ever been discovered. In fact as species diversify and spread into more different ecosystems, adapt to those ecosystems and evolve into new species it is more likely that one will continue to survive than an unchanging population of the parent species. The fossil record is filled with species that lived and then were replaced by newer species.
... Thus dies the Theory of Evolution. Alas, all that dies is your strawman caricature of the theory of evolution. The Theory of Evolution (ToE), stated in simple terms, is that the process of anagenesis (linear or phyletic speciation), and the process of cladogenesis (divergent speciation and the formation of nested hierarchies), are sufficient to explain the diversity of life as we know it, from the fossil record, from the genetic record, from the historic record, and from everyday record of the life we observe in the world all around us. These processes have been observed and that means the theory is supported by objective empirical facts. In addition, nothing has been observed that invalidates this theory, and certainly false and misleading arguments based on misunderstanding evolution do not invalidate the theory.
Fossils show what once lived, they do not necessarily show whether they were related to other fossil forms or not. ... Curiously you are splitting of hairs of much less significance than you think. First fossils are snapshots of individuals rather than of the whole breeding population. Second there are fossil records that show the amount of variation within one generation overlaps with the variation in following generations -- such that many individuals could be members of either population, and the only difference is the time of their appearance in the fossil record:
You can draw vertical lines from the ends of each layer of fossils and see that generation to generation they share the majority of overlapped variations, but that after several generations the then current population has variations that were not found in the original parent population: all P.jarrovii are different from all P.ralstoni ... before dividing into two independent daughter populations, N.nunienus and N.venticolis that don't overlap each other but each overlaps portions of the parent population. These fossils are all found in the same habitat\location, separated only by time, and to ignore the morphological similarities to claim they are not related is more denial than objective consideration. If the morphological change from generation to generation is less than the morphological variation within the populations -- the variation due to microevolution -- and if there is clear geological\ecological continuity, then it is reasonable to see they are just as related as are humans from one part of the world related to others in other parts of the world.
... The idea that birds evolved from dinosaurs is based only on some morphological similarities and position in the fossil record. ... Actually it is based on a majority of morphological overlap of traits and on a continuity of geological\ecological just as is the case for the Pelycodus above. And curiously this overlap of evidence continues to grow as more fossils are found, with more and more intermediates in forms rather than more segregations into distinct unrelated groups. Dinosaurs evolved feathers before they developed flight -- the development of feathers enabled the development of flight from already existing traits in the parent populations.
... We can tell if a fossil was related to a currently living thing by its morphology, but it's sheer speculation to claim descent from one Species to another. And I will agree that some speculation is involved in saying that species (X) evolved from species (Y), but I will disagree on the degree of speculation involved: the speculation is highly informed by the amount of morphological similarities, by the congruity of space and time, and by the intermediates between one population and the next, such that if species (X) did not evolve directly from species (Y) that it must have evolved from a close cousin species to (Y) -- one that could have been a small isolated subpopulation of a parent population to both it and species (Y). Curiously, the theory of evolution does not depend of showing direct unambiguous descent of one species from another, just that the evolutionary processes that we know - and have observed - happen can explain the evolution of one from the other. Does the change in morphology fall with the range of morphological differences possible? Is there a distinct and clear lineage in time and location? And I know you have seen all this before. Enjoyby 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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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined:
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HI Faith,
I have to stop here in your voluminous post. Yes, we both tend to get verbose. If you like we can break it up into multiple posts if length becomes a problem in covering the topics.
Selection certainly applies here as Darwin himself was doing the selecting, at times rather drastically isolating a trait of his choosing and breeding to enhance that trait until the bird was dominated by it to the exclusion of other characteristics. If there was some reason in nature for the development of the same trait you would see Natural Selection at work to the same end. Agreed, but I would also note that the result of natural selection are individuals within a species that are adapted to survive and breed in their ecology, while human selection is for traits that appeal to humans, whether they have any survival or reproductive value, and for that reason a lot of domesticated breeds of pigeon, horses, sows, pigs, dogs and cats have traits that would be disadvantageous in the wild or even lethal without human medical interference. Different purpose → different effect.
His insight was that the selection process occurred naturally, where animals that survived and bred passed their genes (that enabled them to survive and be selected by mates for breeding) to the next generation. Yes, this was his insight but he didn't have the knowledge that would tell him that the changes that occur through selection, natural or artificial, are limited by the fact that selection eliminates alleles in the process of developing new phenotypes. Eventually the new breed or type may be quite strikingly different from others of its kind but it will of necessity have much less genetic ability for any further evolution. ... You've been told and shown and shown and told that this is not true, this belief of yours that no new alleles are produced. There are some examples in other replies to you. Curiously I think Zatara had a good new example in Message 61:
Anyone who has raised identical twins has observed the dramatic effects of mutation in just one generation. Their twins may have started out with identical DNA, having come from the same zygote; however, in just nine months in utero the mutations have yielded differences noticeable to all but a casual observer. Their DNA came from the same original single celled zygote, but during fetal development the process of cell division and duplication and selection for which aspects of their DNA is expressed becomes different as different mutations are incorporated into the development of the individual fetuses -- where did those differences come from if not mutation Faith? Greenish warblers again ... When a trait is selected its genotype is also selected, and alleles for other expressions of the same trait are soon eliminated from the population of birds from which the trait is being bred. If the selection continues generation after generation a point may be reached where ONLY the alleles for the chosen trait are present, all others having been left behind in the original population. if this goes on long enough in nature it is easy enough to see how a subpopulation could develop inability to interbreed with other populations of the same Species, from sheer genetic mismatch ... Curiously we can actually examine this claim in more detail with the Asian greenish warblers (Phylloscopus trochiloides):: different traits in each subpopulation, traits that govern plumage variations and mating and call song variations:
quote: Note that it is hypothesized that the original parent population that these varietals all descended from was "once confined to the southern portion of their range" ... SO: if your hypothesis were true (that varietals only arise by the loss of alleles in the descendant populations) that they would KNOW that one population was the source of the others as it would still have ALL the alleles of ALL the varietals. Sadly (for you), the genetic evidence tells us that no one population has more alleles than the others, to say nothing of combining all of them: there isn't one population that has all the alleles of all the variants. Further note that none of the populations are completely isolated from the others, that there are small overlapping zones between them:
So there isn't complete genetic isolation and gene flow is possible from one end to the other. This gene flow is limited by the distance the individual birds will travel from where there were born to where they nest and mate and rear young during their lives, so gene flow from one end to the other could take several generations. Now I would expect a corollary of your hypothesis (that divergence from a parent population results in loss of alleles) to be that when the populations converge in an overlap zone and interbreed that the alleles would be recombined in the hybrid zones and tend to restore the number of alleles from the original parent population in the hybrid population. Your problem is that there are four such zones -- (1st) between viridanus and ludlowi, (2nd) between ludlowi and trochiloides, (3rd) between trochiloides and obscuratus and (4th) between obscuratus and plumbeitarsus. Which of these is your parent population with the more complete set of alleles? Additionally, with gene flow from each of these hybrid zones to each neighboring varietal zone, we would expect (from your hypothesis) that the intermediate varietals would be hybrids between each of their end (hybrid) zones, ie that ludlowi would be a hybrid between the 1st and 2nd zones, that trochiloides would be a hybrid between the 2nd and 3rd zones, and that obscuratus would be a hybrid between the 3rd and 4th zones, and continuing this reasoning we should see trochiloides as a hybrid between ludlowi and obscuratus, that even if trochiloides was not the original parent population posited in your hypothesis that it should, via convergence of the populations, have characteristics more like this posited parent population that the other varietals. That we do NOT see the hybridizing restoring the full allele distribution to one of these populations means one of two things:
Can you explain how this evidence does not invalidate your hypothesis? Evolution with mutations and natural selection explains these population variations without the problems your hypothesis has. Pelycodus again Now I want you to look at the bottom line in this graph, below where it says P.ralstoni:
Under the "P" there is a thicker line, and this designates where more of the population is found, with the thinner lines to each side designating the variation in the population to each extreme right and left. You will note that these thicker lines stagger back and forth a fair bit as you go up in the diagram to younger populations. If I draw a vertical line from the right end of the bottom population (below "P.ralstoni) ...
Remember that the overlaps from level to level, showing more than 50% of these populations have identical traits, is an indication that they represent the same species/clade breeding population changing over time and adapting to the ecology. Next, If I draw a vertical line from the right end of P.trigonodus I can repeat my questions:
This latter group is now twice removed from the base population that we started with: how do you explain their traits with your hypothesis? Further, if I now draw a vertical line from the left end of P.jarrovii down, then according to your hypothesis that alleles are lost, then ALL the alleles expressed in the base population to the left of this line are now apparently lost in this descendant population, but extending that line up we see traits similar to the original traits returning to the point where N.nunienus seems to recapture most the original traits. Note that the traits involved here are size related traits (size of bones, teeth, body mass, etc), and other traits (coloration, vocalization, etc) are not included so that younger populations would still not appear like the base population even though they now share size related traits. How can you explain this with your hypothesis? Can you explain how this evidence does not invalidate your hypothesis? Note that if you posit that traits can become hidden and then re-expressed later when conditions suit (as you have posited hidden traits that become expressed, as I expect you to claim for traits to the right of my lines - and as you have claimed for the foxes - that this invalidates your claim that the traits are lost and thus results in a death spiral of lost traits). Evolution with mutations and natural selection easily explains these population variations without the multiple contradiction problems your hypothesis has. Foxes again You say nothing about artificially induced mutations here, and there is absolutely no need for them. This change was possible because the genetic material for the chosen traits was already present in the fox genome and could be selected over several generations. This is how all breeds of animals were originally developed, by selection of the traits desired by the breeder, selection meaning basically reproductive isolation of the individuals with those traits. ... Not quite correct Faith -- the ONLY trait selected was tameness, and this was done specifically to make the foxes easier to handle on the fox farms where they are raised for their desired black lush fur. That white spots developed is contrary to what the desired result was. The reason is that tameness is related to adrenalin levels and adrenalin is a hormone that affects fetal development paths, including fur color, ear and tail characteristics. This is about mutations that occur during fetal development because of the different hormonal environment for the fetus. Mutations that affect the timing of development. and Bacteria again Bacteria don't function genetically or reproductively the way sexually reproducing animals do ... Actually the point of bacteria is that cell division and multiplication during fetal development is the same process that bacteria use to reproduce. Thus bacteria developing new traits and fetal development changing to develop new traits (the fox fur, ears and tail traits) are the same process - adaptation to a different chemical environment with new mutations. denial is not evidence ... and I refuse to accept such "evidence." But of course that's the best you can do to answer my obvious points, isn't it? Curiously I think I (and others) have done more than answer your "obvious points" and raised (again) legitimate points that you have yet to answer. Sadly I expect your "answer" to be more denial rather than confronting the evidence. There is a lot more evidence that supports evolution, evidence of mutation providing new alleles, evidence of selection and drift causing an accumulation of new traits in species over time. There is no evidence that traits are only lost and never gained, but there is evidence of traits being gained. Enjoy Moved to Evolution Requires Reduction in Genetic Diversity Message 413 to keep this thread topic on evolution of flight Edited by RAZD, : moved post to more appropriate threaduse peek to see or go to link above Edited by RAZD, : sp in hidden textby 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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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Just caught up. Been a tad sick and so dosed up on meds and sleepy.
I see lots of ground covered since my previous post, and yes it is off topic: do you want me to move my post to the other thread? Thanksby 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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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Welcome to the fray Denisova, are you connected with denisovians discovery?
Is there also a way to move a post to another thread altogether, so not mere copying it but actually replacing? See what I did in Message 204 and Evolution Requires Reduction in Genetic Diversity Message 413 -- you can hide the message when you edit it to copy for the reposting on the other thread, and then one can look (peek) at it if they don't want to go to the other thread. Enjoy ps -- when you |peek| a message the url line gives you f (forum) number, t (thread) number and m (message) number: EvC Forum: Message Peekby 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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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Hi Faith,
I overused my eyes yesterday, have a horrible eyestrain headache and have to be off the internet at least until tomorrow, hope not longer.... and I'll try to deal with the rest of RAZD's post. I've had horrid headaches as well, hence my reduced posting ... Please continue on Evolution Requires Reduction in Genetic Diversity and reply to Message 413 when you are able. Enjoyby 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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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined: |
No, that would be too much credits! Ah well, you never know in a place like this. You realize by now that you are addicted yes?
Re: Moderator Clarification So I ran across this and thought it would be good to discuss in relation to the topic: Beijing to Boston: Chatting About Yi qi, Part 1 | National Center for Science Education
quote: Beijing to Boston: Chatting About Yi qi, Part 2 | National Center for Science Education
quote: It's obviously a dragon Enjoyby 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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RAZD Member (Idle past 1665 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Hi Belcher, and welcome to the fray.
Agreed with you on this point that science can answer many of question but still the science could not justify the death rate and birth rate, the milk phenomenon and many other things you might get the confusing answers from science ... Curiously I am not confused by what is not yet known but excited: science approximates reality by testing explanations against objective empirical evidence, if the explanation fails we toss it and try something else. This way the approximations constantly increase in accuracy.
... but you will get firm answers from a true faith. Hope you got the answer. Question 1: how do you test\know the "firm answer" for accuracy? Question 2: how do you test\know which faith provides the best answer? It is fine to be skeptical of science, but you should equally be skeptical of faith, yes? btw -- if you are interested, we can find a better thread for your questions\answers, as the topic here is specifically about where flying creatures came from: keeping topics focussed helps everyone follow the thread. Enjoy
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quote: also check out (help) links on any formatting questions when in the reply window. For other formatting tips see Posting TipsFor a quick overview see EvC Forum Primer If you have problems with replies see Report Discussion Problems Here 3.0 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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