Believer, I also come here to find out what's new in JW land. An additional reason for me: The forum is a place to test what you believe in. If your faith or facts are flimsy, these will be shot down (and burn). Somewhere in Corinthians Paul explained one must build with fire-resistant materials. I looked it up, 1 Cor. 3:11-15. Another reason, if at all possible, you want to help others.
Posts by Vidqun
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133Why Are You Here?
by Believer ini'm wondering why believers remain members of this forum which is clearly hostile to believers.
as one member said, nonbelievers pounce on any semblance of belief like piranhas on prey.
as former jws we should have had our fill of judgmental know-it-alls, but here we are.
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Proof that Daniel was written 400 years after the events it describes and how much it gets wrong
by purrpurr ini've been studying the bible anew and have just realised that the writer of daniel gets the kings of babylon completely wrong and confused.
he says that nebuchadnezzar was succeeded by his son belshazzar .
then along comes good old cyrus the great who liberates the jews.. yet this is wrong!
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Vidqun
Purrpurr, I guess it depends on how one views the book of Daniel. Perhaps looking from a different perspective might help. The following article was a great help to me:
In his article “The Writing of Daniel,” Jan-Wim Wesselius compares the structure of Daniel to that of Ezra. He refers to the book of Daniel as the Daniel Dossier, a collection of separate documents, dealing with the life, career, and visions of Daniel, which he attributes to the writing style of the author of the book of Daniel. This, he asserts, would account for the discontinuity of the book, being an ancient dossier, unmodified, while retaining some of the characteristics of its sources. At the same time, the assembled material, left relatively unpolished and deviating from chronological order, having all the hallmarks of a complicated history of composition, is structured in such a way that it forms a harmonious whole. I, with Wesselius, ascribe this phenomenon to the brilliance of the author. Wesselius concludes his article: “The book was to appear to its readers as a collection of separate documents, dealing with the life, career and visions of Daniel. At the same time, however, it retained the marks of literary unity, thus inviting the reader to achieve the unity of the book through making his own synthesis of its parts - one of the most successful literary enterprises in history.”
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
Cofty, it's like I am talking to a brick wall. I did my degree approximately 36 years ago, and I haven't work in my field for the last 24 years, so that's why I am somewhat rusty. But that's not important. We are talking in circles, so I have decided to put up a video to explain my stance. I know it's not in my own words, but what the hell, I cannot say it better. It's called "How DNA killed evolutionism," and discusses the laws of information. I am especially fond of the linguistics part. This has been my study field for nearly three decades. Bullshit you might say, but follow the laws of information and work from there. The following paragraphs sum up the main points:
The existence of DNA has proven evolution false and proven both Intelligent Design and Special Creation to be true. It is impossible for evolution to happen or be true because of what genetics has revealed. The reason evolutionists do not give up defending evolutionism despite modern scientific knowledge is because they are dedicated to the materialist idea that they have no creator God to answer to and are not guilty of sin. The evolution theory became prominent in science because certain men of the early 19th century performed a coup in the scientific community by publicly ridiculing men of science who believed in creation, who were the majority at the time, and covertly appointing believers in evolution to key seats in universities and science associations. Among these men were Charles Lyell and others who formed the X-Club for the purpose of displacing creation believers with evolution believers in science circles. This clandestine protection of evolutionism has continued to this day, and it is very difficult and often impossible, depending upon the university, for anyone who does not believe in the fallacy of evolution to become hired as a professor. The opinion of the world public has never fully accepted evolutionism, and the number of it's believers is dwindling because of what science has revealed since the days of Charles Darwin. Eventually, evolutionism will be relegated to history as the greatest and most fervently protected hoax of all time.
Evolution is an ancient religious concept, originating in Dagon and other "gods" who supposedly created man from fish, and picked up again by humanists in the 18th century seeking a logical reason to deny the existence of God in rebellion to His moral law. The basic tenants of evolution such as Natural Selection as a mechanism for evolution were put forth by Greek philosophers in a day when man had little scientific knowledge and before the idea of scientific investigation by observation and testing was conceived. Thales of Miletus put forth the idea that water itself brought forth life, just as the Sumerians, Babylonians, and Egyptians did. Anaximander put forth the idea that all things consisted of fire and water, and this brought forth the universe from nothing - an idea that is known now to be impossible without a supernatural cause. He also said animals came out of the sea and diversified - a claim still held today by evolutionists with their idea that fish evolved into land animals.Democritus claimed the universe was occulting - exploded and imploded continuously - an idea known false by modern astronomy but clung to by evolutionists until Hubble disproved it in the early 20th century. The classification scheme evolutionists apply to life originated with Aristotle, who believed life evolved into various forms from some original form. Humanist god denialist philosophers of the 18th century, picked up the ideas of the ancients thinking they would provide an excuse for denying God, and other humanist attempted to claim that science supported these ancient, false ideas. Evolutionism has never been science or scientific. It is a package of ancient ideas to which modern humanists have attempted to force science to conform. Darwinism in any form is a nonscientific idea which science has destroyed. -
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
Cofty, this is sort of a free-for-all debate with various individuals taking part. I believe it to be good manners to answer those that question me and my motives. And as far as I am concerned, the principles involved here are exactly the same as with endosymbiogenesis and the like. It boils down to the same thing. You believe it happened randomly and spontaneously many aeons ago, and I believe in ID, two philosophies very far removed from each other.
Island Man, very interesting video. This is exactly what I was referring to. There is a certain lack of logic in comparing the syringe of Yersinia pestis to the rotary motor of Escherichia coli, even though they have a molecular similarities. That's like comparing apples to pears.
I like the illustration of the mouse trap, a very simple and basic instrument that can also be used as a tie clip. I wonder who designed the first mouse trap? A clever guy indeed. Who designed the rotary motor of E. coli? Nobody, it designed and manufactured itself: A ridiculous notion indeed! Like I said, if those pathways are discovered one day, I will reconsider my position. Until then I will follow the path of logic which do not lead me to evolution, that's for sure. However, each of you should feel free to follow your own path wherever it leads.
You all seem to have latched on to a common theme, referring to me as a professional microbiologist (I take it you use it as a form of ridicule). I repeat, I haven't practiced Medical Microbiology since the early nineties. My registration with the HRC has lapsed. That's approximately 23 years ago. And no, I did not keep up with the latest developments, as you might have noticed. I have said this before and I say it again. So, let's not harp on this unnecessarily. It serves no purpose whatsoever.
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
WhatshallIcallmyself, I thank you for your educated opinion of right and wrong. I am following the current evidence, which points me to ID. Be assured, when your pathways are discovered, then I will reconsider my position. Until then, I will be led by logic, which I have been trying to explain all this time. I am sorry for those that missed it. That means my teaching ability stinks, so I apologize for that and only that.
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
Shepherdless, debunking indeed! This is how it usually goes: "Bacterial flagella have functions and mechanisms that have differentiated during evolution." In the same breath one then says: "However, the evolutionary history and relationships of these functions and mechanisms remain unclear." See no. 6 above.
Cofty, as you might have noticed, Shepherdless had a problem with my argument of complexity. This drives the point home. And it’s not completely out of context, seeing that it is part and parcel of various bacteria, which are included in our discussion.
While on the subject, I see a third flagellar motor has been discovered. Absolutely brilliant, i.e., the design of the motor and the way it was discovered. Howard Berg's latest paper in Current Biology announces an exciting find: another rotary motor has been discovered in a bacterial cell. The Harvard expert on the bacterial flagellum (see him speaking about the "Marvels of Bacterial Behavior" above), along with two colleagues, describes a new kind of rotating motor in a bacterium, separate and distinct from ATP synthase and the kind of flagella found in E. coli. The short title of the paper is dramatic: "A Rotary Motor Drives Flavobacterium Gliding."
Cells of Flavobacterium johnsoniae, a rod-shaped bacterium devoid of pili or flagella, glide over glass at speeds of 2-4 ?m/s. Gliding is powered by a protonmotive force, but the machinery required for this motion is not known. Usually, cells move along straight paths, but sometimes they exhibit a reciprocal motion, attach near one pole and flip end over end, or rotate. This behavior is similar to that of a Cytophaga species described earlier.... To learn more about the gliding motor, we sheared cells to reduce the number and size of SprB filaments and tethered cells to glass by adding anti-SprB antibody. Cells spun about fixed points, mostly counterclockwise, rotating at speeds of 1 Hz or more. The torques required to sustain such speeds were large, comparable to those generated by the flagellar rotary motor. However, we found that a gliding motor runs at constant speed rather than at constant torque. Now, there are three rotary motors powered by protonmotive force: the bacterial flagellar motor, the Fo ATP synthase, and the gliding motor.
What this implies is even more irreducible complexity for the bacterial flagellum. Without the flagellum+T3SS working cooperatively, the flagellum will not work, because T3SS is "required for secretion of axial components" of the flagellum. This suggests that both the T3SS and the flagellum had to exist simultaneously for the flagellum to assemble properly and function.
The article concludes: "That's a suggestion that will surely be debated between evolutionists and design advocates. What's clear at this point is that another irreducibly complex, functional system for motility has been revealed, based on a rotary engine driven by proton-motive force. Harvard's announcement will certainly stimulate further research into this gliding motor and how it works. Not surprisingly, they feigned no hypothesis about how this system might have evolved." This is certainly music to my ears.
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
Last, but not least, this is how it looks in real life.
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
Sheperdless, simple answer that covers all of the above. I view the complexity in nature is a result of intelligent design, whereas you and your fellow evolutionists believe that it has developed by itself over a long period of time. I believe that is impossible. Something that I would have liked to discuss, but never got round to it, is the inner workings of the bacterial flagellum. This is probably the best demonstration of my argument:
The bacterial flagellar motor is a complex biological rotary molecular motor, which is situated in the cell envelopes of bacteria. Whereas most biological motors use adenosine triphosphate as their energy source, the rotation of the flagellar motor is driven by a flow of charged ions across the bacterial plasma membrane. The motor powers the rotation of helical flagellar filaments at speeds of up to several hundred hertz. These rotating filaments act like propellers, pushing the cells through their environment. The motors are regulated by one of the best characterised biological signalling pathways, the chemotaxis pathway. This pathway changes the swimming pattern of the bacteria in response to changes in the concentration of external chemicals so that they move into environments, which are optimal for their growth. Other pathways can regulate the flagellar motor and the motor itself can respond to changing conditions by adapting parts of its structure.
Many bacteria swim using a small biological rotary motor which is powered by the movement of ions (H+ or Na+) across the plasma membrane.
The bacterial flagellar motor consists of a rotor which rotates against stator units that are anchored to the peptidoglycan cell wall.
Torque is generated by the interaction of the stator units, MotA and MotB (or PomA and PomB for Na+driven motors), with FliG in the rotor.
Despite the fact that the driving ions always flow in one direction through the stator units, many flagellar motors can switch between clockwise and counterclockwise rotation.
The structure of the flagellar motor is highly dynamic, some of its components undergo rapid turnover while the motor is functioning in response to changing conditions.
A complex signalling pathway regulates the motor output in response to environmental signals ensuring that bacteria swim towards nutrient rich environments. 1
1. Bacterial Flagella: Flagellar Motor
Nicolas J Delalez, University of Oxford, Oxford, UK. Published online: August 2014. Full article on Wiley Online Library.
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
Cofty, yes I agree, we are making progress, albeit slowly. First of all, you gave me a list of articles. Click here and take a look for yourself...
Why? Is it in order to prove your Googling skills? I look up the articles and comment on them (not good). I did not bother giving references in order to save time and because you gave me the impression that you were familiar with them and their contents (not good). I can’t put the scientist findings in my own words, I rather let them speak for themselves, thus I am forced to copy & paste (not good). Please make up your mind.
I am honored that you do spend your precious time on my bullshit. And yes, I do look forward to this one: “On the Origin of the Eukaryotic Chromosome.” There’s some interesting words and phrases I want to highlight.
Sheperdless, I thank you for your input and I’m glad you found the quotes interesting. Not sure about your color-car illustration though. Perhaps we should get back to the OP.
Evolution is a Fact #38 - The Origin of Complex Cells
So, no. 1 is directly related to the OP. Are you with me thus far? Now read part of the quote again: “There are still quite a few gray areas in the figure where either the higher plant sequences have not been determined or they are known but the gene phylogeny is insufficiently clear (in our view) to make a statement on the origin of the plant nuclear genes. Chloroplastic and cytosolic pyruvate kinases are a good example of sequenced genes with an evolutionary history that is so intriguingly complex (Hattori et al., 1995) that one cannot yet tell where the plant nuclear genes come from.”
Now the OP claims: Evolution is a Fact. After reading the above, would you say this is the truth or a lie? To add to that, scientists and researchers can’t work out above processes as yet. That means they cannot replicate them either. However, evolutionists claim all these (very complicated) processes originated randomly and spontaneously in a natural environment. Here I beg to differ. In nature, one sees gradual decay, deterioration and disintegration, and not constant improvement as the evolutionist contend. This is contrary to nature and will not change even in a billion years.
No. 2 is supported by the scientists. They are studying endosymbiosis in the Amoeba in order “to study interactions between hosts and infective agents such as Mycobacterium, Legionella, Toxoplasma, Salmonella, and others,” because similar processes are at work in mammals and humans. Coming back to complexity, evolutionists argue that our immune system (highly complex) originated from these processes (very basic and simplified). I find such claims difficult to digest.
No. 3 makes the point that even if the genome of the cells are changed, these remain human cancer cells. Similarly, the nuclear material of Amoeba proteus was changed by endosymbiosis. This is now a variant of Amoeba, resistant to X-bacteria. The process cannot be used to demonstrate a species change, as evolutionists insist (Def.: The term symbiogenesis refers to the genesis of a new species or kind of life through the merger of two or more existing species. Endosymbiogenesis refers to the origin of a new lineage—a sequence of species that forms a line of descent).
No. 4 points to the fact that the process of natural selection do not favor xD amoebae, that underwent endosymbiosis, to survive in a natural environment.
No. 5 reads in part, “This relentless influx of organelle DNA has abolished organelle autonomy and increased nuclear complexity.” If one compares a one-celled organism to a human, I would venture to say that the human qualifies as a super organism, wouldn't you? In other words, the route from a one-celled organism (simplified life form) to a highly complex life form, is a tortuous one with many and huge chasms to overcome.
6. "Members of the recA/RAD51 family have functions that have differentiated during evolution." In the same breath the writer says: "However, the evolutionary history and relationships of these members remains unclear." I have a problem with such statements. Nevertheless, this is typical evolutionary (Cofty) speak because all of them view evolution as a fact. I view it differently.
7. Yup, that happens when guesswork is involved. You get nowhere fast. But remember now, according to evolutionists, in the “primordial soup” all these archaea and bacteria would flourish. How they got there no one can say. These ingest each other randomly, right? From there one would expect all kinds of intermediate forms to exist and develop. By the way, some snails do have chloroplasts, it seems. Or is the composition of a chloroplast so unique and specialized that it is incompatible with a mammalian cell. So a fork in evolution would take place at some juncture that would send archaea, bacteria, fungi and plants in one direction and animals into a different direction with no intermediate forms. This would happen randomly and spontaneously. In my mind that’s a long shot and why evolution should be viewed as a theory and not a fact.
8. At least the researchers are big enough and honest enough to admit this. So if you oppose this point, are you really being honest?
9. Evolutionists insist that in the murky past it was a open process of archaea and bacteria merging to form new organisms, e.g., eukaryotes. Somewhere along the line the open processes became closed, which in our day can only be unlocked and changed by scientists and genetic engineers in specialized labs. It's an interesting concept nevertheless, but highly unlikely.
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Evolution is a Fact #38 - The Origin of Complex Cells
by cofty inin 1966 microbiologist kwang jeon was studying a population of amoebae in the lab when they began to die off unexpectedly.
he noticed thousands of tiny dots in the cytoplasm of each individual which turned out to be a bacterial infection.
most of them weakened and died but surprisingly a small percentage recovered and seemed to be back to normal.
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Vidqun
After going through some of the recommended articles, here’s a few observations (my comments in are in bold letters):
Article: There are still quite a few gray areas in the figure where either the higher plant sequences have not been determined or they are known but the gene phylogeny is insufficiently clear (in our view) to make a statement on the origin of the plant nuclear genes. Chloroplastic and cytosolic pyruvate kinases are a good example of sequenced genes with an evolutionary history that is so intriguingly complex (Hattori et al., 1995) that one cannot yet tell where the plant nuclear genes come from. Furthermore, cases are also known in which the compartmentation of individual gene products can change in different lineages over evolutionary time, such that Figure 2, if prepared for Chlamydomonas or Euglena rather than spinach, would reveal different patterns of origins and compartmentation for the enzymes of the same pathways in those organisms (for an overview, see Martin and Schnarrenberger, 1997).
1) Complexity: The scientists are unable to work out some of the aspects of gene phylogeny in their labs. How could these develop randomly, spontaneously and unaided?
Article: Further work is in progress to determine the mechanism and consequences of the sams gene switching in amoeba/X-bacteria symbiosis. The switch in gene expression in amoebae is not only an example of genetic alterations caused by host-symbiont interactions but also may serve as a good model to study interactions between hosts and infective agents such as Mycobacterium, Legionella, Toxoplasma, Salmonella, and others.
2) Amoebal Immunity: This is a simple immunity mechanism integral to Amoebae, similar to our more complicated immune response. This is not a random process and cannot develop spontaneously. It has been designed that way. In addition, there’s a huge chasm between Amoebal immunity and mammalian immunity, as I remarked earlier.
Article: Various strains of Human Papilloma Virus (HPV) have recently been found to play an important role in the development of cervical cancer. The HPV oncogenes E6 and E7 that these viruses possess have been shown to immortalise some human cells and thus promote cancer development. Although these strains of HPV have not been found in all cervical cancers, they have been found to be the cause in roughly 70% of cases. The study of these viruses and their role in the development of various cancers is still continuing, however a vaccine has been developed that can prevent infection of certain HPV strains, and thus prevent those HPV strains from causing cervical cancer, and possibly other cancers as well.
3) Human cancer cells remain human even though their nuclear material had been altered (not a new species)
Article: As shown by our study on the growth rates of amoebae, xD amoebae are more sensitive to exogenous AdoMet than are D amoebae. It is not known why xD amoebae are more sensitive to AdoMet, but it seems to be related to the fragility of the plasmalemma of xD amoebae. It is known that xD amoebae are more sensitive to overfeeding, starvation, microsurgical operations and elevated culture temperature (Jeon, 1995).
4) Natural selection: Interestingly, the xD amoebae have not been improved. Their chances of survival have been considerably reduced. No super or improved organism with the proses of endosymbiosis, I’m afraid.
Article: Genome sequences reveal that a deluge of DNA from organelles has constantly been bombarding the nucleus since the origin of organelles. Recent experiments have shown that DNA is transferred from organelles to the nucleus at frequencies that were previously unimaginable. Endosymbiotic gene transfer is a ubiquitous, continuing and natural process that pervades nuclear DNA dynamics. This relentless influx of organelle DNA has abolished organelle autonomy and increased nuclear complexity.
5) Theoretically then, super or improved organisms should result from the following processes, even in the lab. We see, this is not the case.
Article: The bacterial recA gene and its eukaryotic homolog RAD51 are important for DNA repair, homologous recombination, and genome stability. Members of the recA/RAD51 family have functions that have differentiated during evolution. However, the evolutionary history and relationships of these members remains unclear. Homolog searches in prokaryotes and eukaryotes indicated that most eubacteria contain only one recA. However, many archaeal species have two recA/RAD51 homologs (RADA and RADB), and eukaryotes possess multiple members (RAD51, RAD51B, RAD51C, RAD51D, DMC1, XRCC2, XRCC3, andrecA). Phylogenetic analyses indicated that the recA/RAD51 family can be divided into three subfamilies: (i)RADα, with highly conserved functions; (ii) RADβ, with relatively divergent functions; and (iii) recA, functioning in eubacteria and eukaryotic organelles. The RADα and RADβ subfamilies each contain archaeal and eukaryotic members, suggesting that a gene duplication occurred before the archaea/eukaryote split. In the RADα subfamily, eukaryotic RAD51 and DMC1 genes formed two separate monophyletic groups when archaeal RADA genes were used as an outgroup. This result suggests that another duplication event occurred in the early stage of eukaryotic evolution, producing the DMC1 clade with meiosis-specific genes. The RADβ subfamily has a basal archaeal clade and five eukaryotic clades, suggesting that four eukaryotic duplication events occurred before animals and plants diverged. The eukaryotic recA genes were detected in plants and protists and showed strikingly high levels of sequence similarity to recA genes from proteobacteria or cyanobacteria. These results suggest that endosymbiotic transfer of recA genes occurred from mitochondria and chloroplasts to nuclear genomes of ancestral eukaryotes.
6) The sentence reads: "Members of the recA/RAD51 family have functions that have differentiated during evolution." The next sentence reads: "However, the evolutionary history and relationships of these members remains unclear." Isn't that accepting things at face value without evidence?
Article: Chloroplasts arose >1.2 billion years ago (1) when a free-living cyanobacterium became an endosymbiont in a eukaryotic host. Since that time, chloroplast genomes have undergone severe reduction, because chloroplast genomes encode between 50 and 200 proteins, whereas cyanobacterial genomes encode several thousand. Accordingly, endosymbiotic theories have always assumed that the cyanobacterial ancestor of plastids relinquished much of its genetic autonomy: “it is not surprising that chloroplasts lost their ability to live independently long ago,” as Mereschkowsky put it in 1905 (2). In today's terms, that means that during the course of evolution, genes must have been transferred from the ancestral chloroplast to the nucleus, where they acquired the proper expression and targeting signals to allow the encoded proteins to be synthesized on cytosolic ribosomes and reimported into the organelle with the help of a transit peptide. This process, a special kind of lateral gene transfer called endosymbiotic gene transfer (3), appears to be very widespread in nature: ≈18% of the nuclear genes in Arabidopsis seem to come from cyanobacteria (4), and obvious remnants of the chloroplast DNA have been found in higher plant nuclear chromosomes (5). Evolutionary biologists have long been able to infer endosymbiotic gene transfer from evolutionary sequence comparisons but have not been able to watch it happen in the lab until now. In this issue of PNAS, Stegemann et al. (6) report gene transfer from the tobacco chloroplast genome to nuclear chromosomes under laboratory conditions. Their findings, together with other recent developments, open up new chapters in our understanding of organelle–nuclear DNA dynamics and have far-reaching evolutionary implications.
7) Mitochondria and Chloroplasts: If things took place randomly and spontaneously, Why did chloroplasts not find their way into the animal and human genome?
Article: Photosynthetic eukaryotes, particularly unicellular forms, possess a fossil record that is either wrought with gaps or difficult to interpret, or both. Attempts to reconstruct their evolution have focused on plastid phylogeny, but were limited by the amount and type of phylogenetic information contained within single genes1, 2, 3, 4, 5. Among the 210 different protein-coding genes contained in the completely sequenced chloroplast genomes from a glaucocystophyte, a rhodophyte, a diatom, a euglenophyte and five land plants, we have now identified the set of 45 common to each and to a cyanobacterial outgroup genome. Phylogenetic inference with an alignment of 11,039 amino-acid positions per genome indicates that this information is sufficient — but just barely so — to identify the rooted nine-taxon topology. We mapped the process of gene loss from chloroplast genomes across the inferred tree and found that, surprisingly, independent parallel gene losses in multiple lineages outnumber phylogenetically unique losses by more than 4:1. We identified homologues of 44 different plastid-encoded proteins as functional nuclear genes of chloroplast origin, providing evidence for endosymbiotic gene transfer to the nucleus in plants.
8) Again, the fossil record is full of gaps and do not support symbiogenesis as the principal mechanism of developing life forms.
Article: The experimental design used by Stegemann et al. (6) was simple and effective. Using a technology called chloroplast transformation (7), they introduced a cassette containing two foreign genes into tobacco chloroplast DNA. The first one encoded spectinomycin resistance (aad) under the control of a chloroplast-specific promoter; the second one encoded kanamycin resistance (npt) under the control of a nuclear-specific promoter. They took advantage of the fact that whole tobacco plants can be regenerated from single cells. By subjecting transformed tobacco tissues to several rounds of selection on medium containing spectinomycin, they were able to obtain tobacco plants that were homoplastomic for aad and npt; that is, all copies of the chloroplast DNA in all plastids in those plants contained the new cassette. By placing small sections of leaves from those aad/npt homoplastomic lines on kanamycin-containing medium, they initiated selection for strong expression of the npt gene under the control of the nuclear-specific promoter. That was the key step, because on kanamycin medium, only such tobacco cells will survive whose nuclear DNA has incorporated a segment of the genetically modified chloroplast DNA containing the new npt gene.
9) Unnatural Gene Manipulation by Researchers: If it was an open, random, spontaneous process to begin with, why is it now a closed process that can only be manipulated with the help of the genetic engineers?
