Conflicts in Common Ancestry: Mitochondrial DNA and the MRCA

Discussion in 'Science' started by usfan, May 4, 2020.

  1. usfan

    usfan Banned

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    This article is about mitochondrial DNA, and the discovery some years back, of a 'marker', that was passed down to daughters, tracing actual descent. It leads to the Most Recent Common Ancestor (MRCA), in genetic lines, and provides hard science for timelines, descent, and relationships.

    First, Definitions:

    From wiki:
    Mitochondrial DNA is the small circular chromosome found inside mitochondria. These organelles found in cells have often been called the powerhouse of the cell. The mitochondria, and thus mitochondrial DNA, are passed almost exclusively from mother to offspring through the egg cell.
    ...
    Mitochondrial DNA was discovered in the 1960s by Margit M. K. Nass and Sylvan Nass by electron microscopy as DNase-sensitive threads inside mitochondria, and by Ellen Haslbrunner, Hans Tuppy and Gottfried Schatz by biochemical assays on highly purified mitochondrial fractions.

    [​IMG]

    From wiki:
    In human genetics, the Mitochondrial Eve (also mt-Eve, mt-MRCA) is the matrilineal most recent common ancestor (MRCA) of all currently living humans, i.e., the most recent woman from whom all living humans descend in an unbroken line purely through their mothers, and through the mothers of those mothers, back until all lines converge on one woman.

    It is a problem for the theory of common descent, as it clearly shows the lines of descent in a particular genetic haplogroup.

    For example, we can trace the descendancy in canids: dogs, wolves, coyotes, etc, even though they have some differences morphologically, they show evidence of descent, and share a common mother.. the Most Recent Common Ancestor that they ALL descended from.

    This marker does not cross over to other speculated ancestors. Humans, for example, share a common MRCA, which shows we all descended from the same mother, and did not evolve seperately, in different geological regions, as was once believed. Neanderthals were human. Pygmies, Mongols, Eskimos, Europeans, Africans.. every race, region and body type of human beings all share the MRCA.. a marker showing descendancy and relationship with all other humans. Chimps, monkeys, apes, or any other speculated 'cousins', do not have this HUMAN MRCA marker, but their own, showing their lines of descent.

    So, while the dingo, dog, wolf and coyote can be traced to a MRCA, humans, apes, and monkeys cannot. Each genetic haplogroup has its own MRCA, and they do not intersect or overlap. There is no evidence of descent.

    Mitochondrial DNA carries a genetic indicator of matrilineal descent, and can trace that descendancy all the way back, to a Most Recent Common Ancestor.. the mt-MRCA. It is ONLY passed on by FEMALES.. mother to daughter. The males get it from their mother, but it stops there. Only the DAUGHTER can pass it on.

    For this reason, the mt-MRCA has been called 'mitochondrial eve,' ..not because the crafters of the phrase believe in the Genesis account of human origins, but as a cultural reference, to western civilization. Most people in western civilization catch the reference to a single 'Mother of all Humanity.'

    The significance of the discovery of the mt-MRCA is often ignored and overlooked:

    1. All of humanity, alive and dead, that has testable dna samples, can be traced to this 'mitochondrial eve'. She is the only, single human ancestor we can identify, and all of us descended from her.
    2. Neanderthal, Pygmies, Eskimos, Norwegians, Aborigines.. any and ALL human people groups, alive or dead (with traceable dna), are descended from this 'mitochondrial eve.'
    3. This 'marker', within the mtDNA, is also present in other organisms, and THEIR ancestral lineage can also be traced. Canids have clear lines of descent, from the original mt-MRCA, in their respective haplogroup/clade/phylogenetic type.
    4. This mitochondrial 'marker' does NOT cross genetic boundaries, but is exclusive to the particular haplogroup. Apes and chimps do not have the human mt-MRCA, nor do humans have any indication of sharing common ancestry with ANY other species/clade/phylogenetic type. Humans are descended from humans. Apes from apes, canids from canids, equids from equids.

    The discovery of the matrilineal ancestry 'indicator', in the mtDNA has been a scientific boon. It has refuted many assumptions and beliefs, that are abundant in the theory of universal common ancestry, and are a problem for those who believe this theory.

    I predict as more information is discovered, especially in genetics, the theory of common ancestry will join the flat earth, the 4 humours, and spontaneous generation, in the dustbin of debunked scientific theories. It has become a Religious Belief, complete with fanatical True Believers, who defend it with jihadist zeal, but they are unable to debate the science behind their beliefs.


    Conflicts in Common Ancestry:
    Transitional Forms
    E.coli
    False Equivalence
     
  2. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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    You seem to have established the legitimacy of the missing link between chimps/gorillas and humans as something permanently missing because it never existed. I suggest that the gap was bridged by a radical mutation. There is now sufficient evidence indicating that there have been incidents of drastic cosmic disturbances causing the release of high levels of solar radiation.

    Evolutionary history is rife with new lifeforms appearing within relatively short periods of time. E.G., there was a time when there were no vertebrates but mostly invertebrates and marine arthropods. At another later time there were marine vertebrates but no land animals. Further on there were amphibians but no reptiles or mammals, and so on.

    Embryonic morphology shows the transitional overlap between humans and the rest of the animal kingdom. The workable blueprint is there. We are the product of radial changes. A few of our chromosomes are fused together. Although we gained a lot that put us in a class superior to chimps, we lost some advantages, such as the genetically conferred resistance to heart disease possessed by apes.

    The potential is there for us to be on a trajectory towards higher intelligence and higher consciousness.
     
    Last edited: May 4, 2020
  3. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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    Err, I meant radical, not radial. The C-key on my laptop has become unresponsive to the usual light pressure.
     
  4. An Taibhse

    An Taibhse Well-Known Member

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    Let’s see, on one hand you reject the concept of descent from common ancestry... ‘It is a problem for the theory of common descent’ and yet you cite the article you copy and pasted with the interpretation of that ‘it clearly shows the lines of descent in a particular genetic haplogroup’. Hmmm no contradiction there, eh? You liked the reference given of the suggestion of a common ancestor referred to eve. Lol
    You still clearly do not understand, nor care to understand how genetic change in a biological population occurs as a product of natural selection. Each and everyone of us has a genetic record of that change in our DNA.
    Interestingly, the Covid-19 virus is providing an almost real-time model of genetic change and the change in the virus DNA is being tracked,
    https://www.nytimes.com/interactive/2020/04/30/science/coronavirus-mutations.html
    https://phys.org/news/2020-04-genome-variation-insight-coronavirus.html
    https://www.sciencenews.org/article/coronavirus-genetic-fingerprints-are-used-to-rapidly-map-spread
    Unless there are multiple sources of the Covid-19 virus suddenly appearing from multiple unknown sources, it would appear, there is a common ancestor. Or, is each variant some new manifestation of an intelligent designer?
     
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  5. Moi621

    Moi621 Well-Known Member Past Donor

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    @An Taibhse
    @usfan
    @Gelecski7238

    Consider the uniqueness of women being fertile once a month
    as opposed to a few times a year.

    It is suggested Eurasians were more like a few times a year while
    the "out of Africa" sorts were monthly.
    Breeding advantage that may explain the discrepancy in mitochondrial DNA
    vs corporal DNA.
    Asiatic Cheekbones appear in Chinese H. erectus. ;)

    An E-Friend who raises goats told me the same fertility
    issue appear between African goats vs European goats.


    Bad Headache Day. Hope the above makes since.
     
    Last edited: May 5, 2020
    usfan and Sallyally like this.
  6. An Taibhse

    An Taibhse Well-Known Member

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    So, you say ‘there is no evidence of descent’, a flat unequivocal statement and then present an argument of Mitochondrial DNA being inherited along matrimonial lines’.

    Your entire post is contradictory.

    What’s this? Is it somehow meaningful?

    That species have descended from those preceding them and the evidence for divergent organisms sharing common ancestry is recorded in DNA. In fact, that all life as we currently know it has common ancestry can logically be inferred by the fact that all life is DNA based.
     
  7. Moi621

    Moi621 Well-Known Member Past Donor

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    MAJOR
    YAWN!

    Go get a room at Red Robin Inn.
    They'll leave the light on for you.
     
  8. An Taibhse

    An Taibhse Well-Known Member

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    What you are somewhat referring to is something first referred to by Ernst Mayr in the late 60’s who studied speciation among bird populations and the proposed as a Theory of Punctuated Equilibrium by Niles Eldredge and Stephen Jay Gould in the early 70’s. It wasn’t a Theory, more properly was a hypothesis to address the arguments of critics of evolutionary theory who were suggesting the incomplete fossils record was evidence against the Theory of Evolution. However, when this theory was presented, DNA research was at it’s early stages, and would in the years since provide a basis for understanding genetic history that didn’t need an explanation based on Punctuated Equilibriums; the biological means of DNA replication and the inherent errors associated with DNA replication along with, the concept of natural selection, a map of how genetic change occurs and propagates in a population and even results in speciation... something Ernst Mayr and other investigators have observed since. The rate of genetic change in a population can be for more rapid than Mayr, Eldridge, and Gould might have suspected, for instance in virus populations like the common flu, genetic change is far more rapid than once believed.
    https://www.nature.com/scitable/topicpage/dna-replication-and-causes-of-mutation-409/
    And, for some time now based on empirical research it has become recognized,

    And I suggest, the basis of evolution and life form adaptation is a function of the DNA pattern exhibited by all life. While those of you clinging to some variant of an intelligent creator and intelligent design would have a difficult time refuting Evolutionary Theory given the advancement in our increasing knowledge of genetics, I suppose you could claim the underlying mechanism for life’s propagation and ability to adapt given the Nature we’ve discovered of DNA, DNA was a product of brilliant ‘Intelligent’ design. But, I think there is more to learn... stay tuned.
     
  9. An Taibhse

    An Taibhse Well-Known Member

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    Sorry to put you to sleep.
     
  10. usfan

    usfan Banned

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    Even the BELIEF in punctuated equilibrium is just that:

    A Belief.

    There is no evidence it happened, just plausibility masquerading as 'science!'

    We have evidence for micro evolution, aka adaptation. But there is NOTHING to support the BELIEF in universal common ancestry.

    That remains a leap of faith, that the scientific evidence is debunking, the further we advance in our knowledge base.

    'Embryonic morphology', is just a 'looks like!' fallacy, pretending to be science.

    Ad hominem deflections aside, the point here is that making a false equivalence between micro evolution (adaptation, breeding), is NOT the same as macro evolution, or the belief in common ancestry.
    Outrage and indignation that your beliefs are being questioned is not a rebuttal. The SCIENCE suggests that there is only divergence and separation IN CLADE, and that no 'new!' organisms are 'evolving!'

    Similarity of design and construction is not evidence of common descent. DNA does not 'prove!' common ancestry. If anything, the facts about genetics are a major problem for the belief in common ancestry.

    We can ONLY trace descent IN CLADE, there is no evidence of organisms jumping the genetic fence, and becoming a new phylogenetic structure.

    Man has always been man. There is no evidence we descended from some ape-like hominid. That is a religious belief, with no scientific basis.
     
  11. WillReadmore

    WillReadmore Well-Known Member

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    You suggest that evolution will be discounted at some future time.

    You state that all you have is your belief that some future discovery will invalidate what has been studied for ~150 years and is today a foundation of ALL biological science.

    You admit the evidence is not there for your claim. And, you have no alternative theory that you bother to support.

    ==> Why do you keep posting that?
     
  12. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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    Under average stabile environmental conditions the mutation rate would tend be due to uncorrected errors in DNA replication as described in the link. However, emphasis on the natural rate without due consideration for the accelerated rate under drastic conditions is not wise, just as it was never wise for pundits to assume that the rate of geologic changes in the past was always comparable to the currently observed rate. The phenomenon of something like Punctuated Equilibrium can't be so easily dismissed. Scientists have recorded unusual increases in genetic mutation rates just from serious disturbances in the radiation belts around our planet. The link also acknowledges the fact that environmental agents can cause mutations.
     
  13. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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    Regardless of belief or nonbelief, there is something that looks like punctuated equilibrium in the fossil record, else it probably would never have been contemplated.

    Is there a better way to explain the presence of amphibians without reptiles or mammals until the later arrivals also showed up in the fossil record? There's no proof of universal common ancestry, but its inference is hard to contest.

    There's no escape from it. Other posters have pointed out the early embryonic features that are common between widely differing types of creatures.

    If I recall correctly, another poster cited the tweeking of embryonic genes that led to growth of structure typical of an unrelated type of animal.
     
  14. usfan

    usfan Banned

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    I said,
    ..to another poster.

    Hardly. The theory of universal common ancestry has little useful consequence, in any of the hard sciences. It is an ear tickling, philosophical extrapolation, that has no scientific basis.
    I have posted plenty of evidence debunking the superstitious claims of universal common ancestry. The evidence is overwhelming. Why do you accuse me of this?
    I don't. This is a false accusation. I see plenty of problems, conflicts, and fallacies, in the 'debate' over universal common ancestry. I point them out from time to time, like i did in this thread.

    You could address the topic, and tell me how these 'new species!' are created by common ancestry , when all the genetic evidence says it is impossible.

    But you seem to prefer projecting some psychobabble analysis, to deflect from the complete lack of evidence for this absurd religious belief.
    That is just a testament to the human imagination. The facts and scientific methodology do not compel a conclusion of 'punctuated equilibrium!', nor is embryonic development a 'snapshot!' of evolution. The embryonic 'tail', may 'look like!' a fish tail, but it is not. The genes are different. The development is different. The end result is different. Projecting 'Evolution!' on the similarity of development with living things is a leap of faith. It is not evidence for common descent. It is evidence of similarity of design.

    Projecting plausible imaginations onto the fossil record is not hard science. It is imagination run amok.

    There are many plausible explanations for the observations in the fossil record, and they are based on myriads of unproved assumptions. Concluding 'punctuated equilibrium!' because of alleged gaps in the fossil record is an imaginative speculation, to dodge the problems of belief in uniformitarianism.

    I do not recall any such 'tweaking', that can create a viable genomic structure. Such beliefs are sci fi, and the fodder for movies. There is no science to compel a conclusion of 'common ancestry!'

    I challenge anyone to post ONE EVIDENCE of universal common ancestry. Not belief
    Not plausibility. Not eye rolling outrage over skepticism for this imaginative belief.. but ACTUAL SCIENCE, that shows descendancy between diverse genomic architecture.

    Ape to man
    Reptile to bird
    Amoeba to fish

    There is ABSOLUTELY NO EVIDENCE. that any of these imagined transitions took place. It is only believed, by unscientific indoctrinees, and religious ideologues.
     
  15. WillReadmore

    WillReadmore Well-Known Member

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    Ape to man? Humans and apes came from an early life form. A population divided and the two (or more) divisions moved in different directions.

    Reptiles to bird? Evidence shows that certain reptiles did gradually change toward birds while other populations of reptiles evolved in other directions.

    Amoeba to fish??

    I think your big problem is that you wish you could have lived for hundreds of thousands of years, so you could watch evolution over the time it takes for significant change.

    But, you don't get to do that.
     
  16. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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  17. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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  18. Gelecski7238

    Gelecski7238 Well-Known Member Past Donor

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    Replying to usfan in the quote previous to the one above but out of sequence here due to accidental diversion:

    The inference of common ancestry rests on ground that is no more shaky than conviction and belief in a Creator and his decrees on salvation and retribution, for which there is also no accepted consensus of scientific evidence. Yours is the default position due to the claimed shortcomings of scientific evidence for common ancestry and your conviction based on personal perception of an agent of Holy Authority, a position not readily imparted in those who are not overtly receptive to its conveyance. The debate appears to be a draw.
     
  19. WillReadmore

    WillReadmore Well-Known Member

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    I do see it as progress to note that there are significantly different tool sets - that of religion and that of science. If that can be accepted, I'd count that as progress.

    It helps identify what kind of questions belong in the realm of science and what kind of questions belong in the realm of religion.

    That's a good step, as it improves the chances of reducing conflict caused by choosing the wrong tool or failing to recognize what tool set the other person is using.

    It helps people to understand that scientists, universities,, etc. aren't actually evil. Maybe it incourages people to investigate how science works!
     
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  20. usfan

    usfan Banned

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    ..so you believe. So you assert, without any evidence. That is just a religious belief, based on the assumption of atheistic naturalism.

    No, that is believed and assumed, as a plausible scenario. There is no hard evidence that anything like that is happening, happened, or could happen. An imaginative tree of life has been drawn up that illustrates this belief, but that is not evidence. It is an assertion of belief.
    I wish nothing of the sort. I look for facts and scientific methodology, in a 'theory' that hinges entirely on conjecture and plausibility.

    Hiding behind long time frames is a dodge, not evidence that this alleged event took place.

    Force ANY 'transition' in a lab. Make an amoeba into a more complex form. You cannot. You cannot define a mechanism that does this religious fantasy. You can only declare unwavering faith, that your beliefs are 'science!", when they sre nothing but philosophical constructs.
     
  21. usfan

    usfan Banned

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    I tend to agree, that the BELIEF in common ancestry is religious, at its core, but this is the science subforum, and I'm not pitching creationism, which is clearly labeled 'religion!', here, but am critiquing the SCIENTIFIC basis of common ancestry.

    The inference is, of course, that if common ancestry is flawed, or proven false, as a plausible explanation for origins, then that leaves only creationism as the other option. THAT is the Elephant in the room, that looms large in any scientific debate on origins.

    This thread is a scientific discussion about a flaw in the theory of common ancestry. I cannot help the implications that some will feel, that trigger them into outrage, hostility, and religious hysteria. I can only examine the science, and point out flaws in the theory.

    Mitochondrial DNA is one such flaw. The MRCA points to much shorter time frames than common ancestry needs. Descent is clearly limited by the variability ALREADY PRESENT in the parent stock. I analyzed a study on canidae some time back that illustrated this very problem. I'll repost it.
     
  22. usfan

    usfan Banned

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    This thread seems to be going to the dogs, so an examination of canidae seems to be warranted. I have a study about mtDNA in canids to examine. Here is the title & abstract:
    Relaxation of selective constraint on dog mitochondrial DNA following domestication
    Susanne Björnerfeldt, Matthew T. Webster, and Carles Vilà

    Abstract
    The domestication of dogs caused a dramatic change in their way of life compared with that of their ancestor, the gray wolf. We hypothesize that this new life style changed the selective forces that acted upon the species, which in turn had an effect on the dog’s genome. We sequenced the complete mitochondrial DNA genome in 14 dogs, six wolves, and three coyotes. Here we show that dogs have accumulated nonsynonymous changes in mitochondrial genes at a faster rate than wolves, leading to elevated levels of variation in their proteins. This suggests that a major consequence of domestication in dogs was a general relaxation of selective constraint on their mitochondrial genome. If this change also affected other parts of the dog genome, it could have facilitated the generation of novel functional genetic diversity. This diversity could thus have contributed raw material upon which artificial selection has shaped modern breeds and may therefore be an important source of the extreme phenotypic variation present in modern-day dogs.


    I will quote some of the findings of this study, as well as their conclusions & my own observations. This study is by evolutionists, with the assumption of evolution throughout.

    In The Origin of Species, Darwin (1859) suggested that “several wild species of Canidae have been tamed and that their blood, in some cases mingled together, flows in the veins of our domestic [dog] breeds”. We now know that dogs (Canis familiaris) are entirely derived from the domestication of wolves (Canis lupus) (Vilà et al. 1997); however, the origin of the huge morphological diversity that led Darwin to his speculation remains largely unknown (Sutter and Ostrander 2004). The domestic dog is the most phenotypically diverse mammal on earth. The large differences in size, conformation, behavior, and physiology between dog breeds exceed the differences among species in the dog family, Canidae (Coppinger and Coppinger 2001; Wayne 2001). Recent studies show that the origin of most dog breeds may derive from very recent selective breeding practices and are probably <200 yr old (Parker et al. 2004). However, selection acts upon existing variability. It is remarkable that the potential for such large diversification existed in the ancestral wolf population from where the domestication process was initiated. Furthermore, the time since domestication (at least 14,000 yr; Vilà et al. 1997; Sablin and Khlopachev 2002; Savolainen et al. 2002) seems insufficient to generate substantial additional genetic diversity. What is the origin of this diversity? We hypothesize that changes in the living conditions of dogs as a result of domestication resulted in the release of selective constraint allowing a faster accumulation of functional (non-silent) genetic diversity in a large array of genes.

    This paragraph is packed with important information, facts, & observations about the domestic dog. I will provide a summary:

    1. The dog is the most diverse mammal on earth.
    2. The origin of most dog breeds are recent, less than 200 yrs
    3. The diversity found in the variant dog breeds were ALREADY PRESENT in the ancestral wolf
    4. The time since domestication is insufficient to generate the genetic diversity, according to evolutionary timelines

    They go on to hypothesize a theory about how these traits could have come about, calling it 'selective constraint', a mechanism with no evidence or observable reality, but they must have something to make up for the flaws in the lack of time to 'evolve' the diversity that we obviously observe.

    Weakly deleterious mutations—those with selective effects close to the reciprocal of the effective population size—represent an important class of genetic variability (Ohta and Kimura 1971). Such mutations are expected to accumulate faster in populations with small effective sizes or in populations in which selection has been relaxed, resulting in a decline in fitness. Advantageous mutations, conversely, contribute little to patterns of genetic variation and are enriched in fixed differences between species. To examine whether the accumulation of deleterious mutations is increased in dogs compared with their wild ancestors, we have focused on mitochondrial DNA (mtDNA). The mitochondrial genome represents only a small part of the canine genome and has a unique mode of inheritance. However, while dog and wolf lineages are difficult to separate for nuclear genes (Parker et al. 2004; Vilà et al. 2005), mitochondrial lineages are clearly distinguishable for the two species (Vilà et al. 1997; Savolainen et al. 2002). This offers a good opportunity to evaluate the consequences of life with humans on a portion of the dog genome.

    1. Deleterious mutations 'are expected' to accumulate faster. This is not anything observable, or repeatable, but is an assumption, to promote the 'theory' of increasing complexity.
    2. 'Advantageous mutations' (undefined) don't contribute much to genetic diversity, but show as fixed traits in the different breeds. That is, the 'theory' of 'advantageous mutations' don't create variability. The traits are FIXED within the breeds, which is observable, obvious reality. That is how we are able to isolate traits in the science of breeding.
    3. mtDNA provide clearly distinguishable lineages in the canid family.

    Mutation is still the assumed mechanism, though there is NO VISIBLE, OBSERVABLE MECHANISM provided that can explain how any traits can be 'created'. Time cannot do it. 'Accumulated deleterious' mutations cannot do it. 'Advantageous mutations' don't even occur. Fortunately, the discovery of DNA, & especially mtDNA can provide SCIENTIFIC proof of descendancy, instead of 'looks like' taxonomy & speculation.

    Previous studies have shown that domestic dog mtDNA sequences cluster in four main clades when compared with wolves, indicating different origination events (Vilà et al. 1997; Savolainen et al. 2002). In order to select samples of dogs representing several mtDNA lineages for the analysis, we sequenced the mitochondrial control region I for 88 dogs from 53 breeds. Among those individuals we selected 14 dogs, which included six from clade I (the clade that encompasses about 71% of today’s dogs; Savolainen et al. 2002) and two or three from each one of the clades II, III, and IV (Vilà et al. 1997). Because we wished to characterize mutations that occurred on dog lineages since the emergence of each clade, the dogs in this study were selected to be representative of the full genetic diversity observed in each clade (Supplemental Fig. S1). Complete mtDNA sequences, excluding the tandem repeat located inside the control region (Hoelzel et al. 1994), were obtained through polymerase chain reaction (PCR) amplification and sequencing. The complete mitochondrial sequence was also obtained for six wolves from throughout the world trying to represent as much of the previously described wolf diversity (Vilà et al. 1999) as possible: Spain, Russia, Saudi Arabia (two individuals), North America, and Sweden. Three coyotes (Canis latrans) from Nebraska and Colorado (two individuals), USA, were also sequenced and used as outgroups.

    To construct a gene tree from the 23 complete mtDNA sequences, we first excluded the control region because of the high incidence of homoplasy (Ingman et al. 2000), resulting in a sequence length of 15,547–15,549 base pairs (bp). The average uncorrected pairwise sequence divergence between wolves and dogs was 0.47% (SE = 0.02), whereas average sequence divergence between coyotes and dogs plus wolves was 4.28% (SE = 0.11). A gene tree constructed with these sequences shows that all four clades of dogs are very well supported with bootstrap support values of 100% and Bayesian posterior probabilities of 1.00 (Fig. 1).


    This is a description of the study, & the parameters of the mapping. Here is the graphic they devised to display the findings

    [​IMG]

    Fig. 1. Phylogenetic tree of wolf (W), dog (D), and coyote (C) mtDNA sequences. The tree was constructed using a Bayesian approach. The same topology was obtained with a neighbor-joining approach. Support is indicated at the nodes as percent bootstrap support for 1000 neighbor-joining replicates and Bayesian posterior probabilities. Four clades of dog sequences (I to IV) are indicated as in Vilà et al. (1997). Internal dog branches are marked in orange, and internal wolf branches are marked in light blue. The branch leading to wolf haplotype W1 was basal to the rest of the tree and it was also considered internal. Internal branches that could not be conclusively associated to dogs or to wolves are indicated in discontinuous green.

    As you can see, the mtDNA shows the ancestry line. The canid ancestor preceded the wolf, the dog, & the coyote, as well as other canid not listed. I have seen them in other genetic studies. Here are the facts about this study:

    1. The modern wolf breeds, coyotes, & domestic dogs are all descended from a common ancestor, as is proved by the mtDNA.
    2. Some branches of the trees can be followed, showing further narrowing of variability, & lessening of the trait options in the DNA
    3. All of the original traits of ALL the subsequent breeds were ALREADY PRESENT in the canid ancestor.
    4. The current set of breeds in canidae are mostly dead ends.. the limits of the branches in the family tree, & no longer have the original variability within the ancestral canid.

    The study continues, & i can highly recommend it for a better understanding of genetics in mammals. I don't think all the conclusions or speculations are supported, but the facts of the study are very enlightening.

    source
    http://genome.cshlp.org/content/16/8/990.full
    Quotes from study are in italics.

    This post was reposted from a closed thread from 2016.
    http://www.politicalforum.com/index...w-of-evolution.442211/page-12#post-1065910061
     
  23. WillReadmore

    WillReadmore Well-Known Member

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    There is massive evidence from throughout biology.

    I see no way of discounting that evidence, and I certainly see no way of explaining how the entire world of biological science can be discounted with the nonsense yoou propose.
    That tree is not imaginative. It's based on several different kinds of evidence. We have dna that is more than half a million years old, for example. Changes in humans have happened within that time. And, scientists can watch speciation in labs in species that have short life spans so many generations can be watched. By now, there are a number of known paths of speciation that come from various kinds of changes at the cellular leve.

    Beyond that, evolution makes very strong statements concerning what will be found in nature. EVERY deceased life form that has ever been found is a test of evolution theory.

    And, let's remember that there is NO competing theory.
    No, you reject scientific method.
    This is total nonsense. Long time frames are required for signficant change for very obvious reasons.
    I have NO idea what you mean concerning forcing a transition. Evolution doesn't include a method for such force. This is just your lack of understanding of evolution.

    Mankind HAS strongly affected a significant number of plants and animals through evolution by humans providing the selection.
     
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  24. WillReadmore

    WillReadmore Well-Known Member

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  25. Cosmo

    Cosmo Well-Known Member

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    The more research that's done on DNA the more evidence we find that all life is related.

    In the last couple of decades our understanding of genetics has grown dramatically, providing overwhelming evidence that we share common ancestors with all life on earth.
     
    Last edited: May 9, 2020
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