Chemical evolution:

[iceaura]

You may want to read up on Robert Hazen and why chirality is essential in the evolutionary process.

Quote ambiguously attributed.
Hazen's contribution is largely irrelevant to my point - I simply noted that chiral molecules and chirality-influenced chemical interactions were common and readily available for "evolutionary process" to work with.

No in practice clays and similar inorganic 'templates' only weakly offset purely racemic mixtures.

That's easily sufficient - chiral molecules were abundant on the entire surface of the planet, and many of them (the clays, some crystals, lots of organics, anything with magnetic moment, etc) were capable of copying themselves, spreading via mechanical and other environmental forces, and so forth.
It's important to remember that the modern extraordinary efficiency of living beings was completely unnecessary. If it took months and miles instead of minutes and micrometers to duplicate something, that was ok - nothing was stopping it.

 

[dumbest man on earth]

If you and Tour understand abiogenesis so clearly, then why are you compelled to introduce mysticism into the equation?

Clearly, you do not understand the definition of the therm "evolution" from simple to more efficient complex forms.

Outline of evolution


A diagram showing the relationships between various groups of organisms

Contents

• 1Fundamentals about evolution
  • 1.1Introduction
  • 1.2Basic principles
  • 1.3Subfields
  • 1.4History
• 5Applications in other disciplines
• 6Evolutionary issues
  • 6.1Controversy about evolution
  • 6.2Religious and philosophical views of evolution
  • 6.3Influence of evolutionary theory
• 7Publications and organizations concerning evolution
  • 7.1Books
  • 7.2Journals
  • 7.3Organizations
• 8Evolution scholars and researchers
  • 8.1Prominent evolutionary biologists
• 9See also
• 10External links

Earliest Earth (−4540)
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Earliest water
←
Earliest life
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LHB meteorites
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Earliest oxygen
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Atmospheric oxygen
←
Oxygen crisis
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Earliest fungi
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Sexual reproduction
←
Earliest plants
←
Earliest animals
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Ediacaran biota
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Cambrian explosion
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Tetrapoda
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• Introduction to evolution – non-technical overview of the subject of biological evolution
• Evolution – change in the heritable characteristics of biological populations over successive generations
• Evolution as fact and theory – A discussion of the meaning and usage of the terms evolution, fact and theory

Basic principles[edit]

• Macroevolution – Evolution on a scale at or above the level of species
  • Speciation – Evolutionary process by which populations evolve to become distinct species
    • Natural speciation
      • Allopatric speciation – Speciation that occurs between geographically isolated populations
      • Peripatric speciation – Speciation in which a new species is formed from an isolated smaller peripheral population
      • Parapatric speciation – Speciation within a population where subpopulations are reproductively isolated
      • Sympatric speciation – A process through which new species evolve from a single ancestral species while inhabiting the same geographic region
    • Artificial speciation
      • Animal husbandry – Management, selective breeding, and care of farm animals by humans
      • Plant breeding – The art and science of changing the traits of plants in order to produce desired characteristics
      • Genetic engineering – Direct manipulation of an organism's genome using biotechnology
    • Hybrid speciation – Form of speciation involving hybridization between two different species
  • Despeciation – The loss of a unique species of animal due to its combining with another previously distinct species
  • Anagenesis – Gradual evolutionary change in a species without splitting
  • Extinction – Termination of a taxon by the death of the last member
• Microevolution – change in allele frequencies that occurs over time within a population
  • Artificial selection – Process by which humans use animal and plant breeding to selectively develop particular phenotypic traits
  • Natural selection – Mechanism of evolution by differential survival and reproduction of individuals
    • Sexual selection – Mode of natural selection involving the choosing of and competition for mates
  • Mutation – Alteration in the nucleotide sequence of a genome
  • Gene flow – The transfer of genetic variation from one population to another
  • Genetic drift – The change in the frequency of an existing gene variant in a population

If you understand abiogenesis so clearly, then why are you compelled to introduce "evolution" into the equation?
You seem to be conflating an unexplained hypothesis, abiogenesis - life from non-life, and an actual scientific theory that begins with the premise that life already exists.

 

[Write4U]

Quote ambiguously attributed.
Hazen's contribution is largely irrelevant to my point - I simply noted that chiral molecules and chirality-influenced chemical interactions were common and readily available for "evolutionary process" to work with.

IMO , there is more to it than that.

Cell chirality: its origin and roles in left–right asymmetric development

In general, protein functions depend on interactions with other molecules via chiral structures. For a gene to encode a protein with a specific shape, the homochirality of amino acids is required, because L- and D-amino acids will give rise to different three-dimensional protein structures. Thus, the homochirality of amino acids is essential for the basic execution of genetic control. In addition, an enzyme usually has a chiral groove or binding pocket that fits one enantiomer of its substrate but not the other. Thus, the homochirality of biologically active molecules is a critical condition for the molecular functions of organisms.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5104503/#

That's easily sufficient - chiral molecules were abundant on the entire surface of the planet, and many of them (the clays, some crystals, lots of organics, anything with magnetic moment, etc) were capable of copying themselves, spreading via mechanical and other environmental forces, and so forth.
It's important to remember that the modern extraordinary efficiency of living beings was completely unnecessary. If it took months and miles instead of minutes and micrometers to duplicate something, that was ok - nothing was stopping it.

I'm not sure if I agree with that. Seems to me that nothing in Nature is abundant without being subject to natural selection and having some underlying advantage. The abundance of both speaks of the essential role they play in the evolution of biological organisms.

Cell chirality: emergence of asymmetry from cell culture

Increasing evidence suggests that intrinsic cell chirality significantly contributes to the left–right (LR) asymmetry in embryonic development, which is a well-conserved characteristic of living organisms. With animal embryos, several theories have been established, but there are still controversies regarding mechanisms associated with embryonic LR symmetry breaking and the formation of asymmetric internal organs.

Recently, in vitro systems have been developed to determine cell chirality and to recapitulate multicellular chiral morphogenesis on a chip. These studies demonstrate that chirality is indeed a universal property of the cell that can be observed with well-controlled experiments such as micropatterning.

In this paper, we discuss the possible benefits of these in vitro systems to research in LR asymmetry, categorize available platforms for single-cell chirality and multicellular chiral morphogenesis, and review mathematical models used for in vitro cell chirality and its applications in in vivo embryonic development. These recent developments enable the interrogation of the intracellular machinery in LR axis establishment and accelerate research in birth defects in laterality.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5104512/

 

[iceaura]

Seems to me that nothing in Nature is abundant without being subject to natural selection and having some underlying advantage.

The inorganic and organic molecules that covered the planet in the eons before life were often chiral, and abundant enough to cover the planet. Likewise water, silicon and aluminum and carbon compounds, that kind of stuff.

IMO , there is more to it than that.

Sure - so?
There was plenty of chirality available for "evolutionary process" to work with in the eons before life emerged, is all I'm saying.

 

[Write4U]

If you understand abiogenesis so clearly, then why are you compelled to introduce "evolution" into the equation?

Because evolution by natural selection in both chemistry and biochemistry is a demonstrable process of all things in the entire universe.

You seem to be conflating an unexplained hypothesis, abiogenesis - life from non-life, and an actual scientific theory that begins with the premise that life already exists.

The notion of "irreducible complexity" has been debunked, not just scientifically , but in a Court of Law, based on the evidence presented . (See the Kitzmiller v Dover Trial)

Ask yourself this question: "Is a male sperm alive?" The answer is YES, it’s certainly as alive as any other cells in a male body. Since it can have a life of its own outside the body, each sperm is really an independent single-celled organism – like a living amoeba, but differing in locomotion and lifestyle.

Now ask yourself this question: "Is an unfertilized egg alive?". The answer to this is NO, and at the same time answers the question of the abiogenetic process which transforms a non-living (unfertilized egg) into a living object able to replicate and grow after "fertilization". What better proof can be presented?

Life is not a mysterious thing at all. Look around you and see the incredible variety of life and living organisms which inhabit this earth. And then to think that 95 % of all life on earth is extinct.

 

[paddoboy]

No you haven't shown any such thing.

Sure I have! His "preacher" like account from your link, and the little bit of that nonsense I watched proved that.

And frequent recourse to 'fanatical nut' or 'usual conspiracy nonsense' and similar unjustified/skewed put-downs is an extremely poor way to argue a case. But a leopard can't change it's spots.

Not at all! and his fanatical acceptance of the bible and rejection of science in some of the links also prove that. Would you like me to quote some of that extraordinary nonsense?

I didn't join up at SF with the intention of discussing ID vs blind evolution. At a certain point I decided to join the debate. To construe that as 'coming out of the closet' is stupid and offensive. But that's part and parcel of paddoboy's MO.

I construed it as I saw it, and probably before most, and certainly no more offensive then declaring Tour for the fanatic he is, and the eager, gullible way you latched onto him.

No conspiracy there at all. Only in your head. And btw, societies have nearly always been run by conspirators, ever since the dawn of civilization. Naive to think otherwise.

You are known to push conspiracies q-reeus, most inane and stupid. The rest is crap.

Tour is a world renowned synthetic organic chemist.

So? You latch onto one "world renowned synthetic organic chemist " as opposed to a multitude of other world renowned synthetic organic chemists? And one who in his fanaticism has also avowed to continue to dismiss any new evidence for abiogenesis.

 

[Write4U]

The inorganic and organic molecules that covered the planet in the eons before life were often chiral, and abundant enough to cover the planet. Likewise water, silicon and aluminum and carbon compounds, that kind of stuff.

Sure - so?
There was plenty of chirality available for "evolutionary process" to work with in the eons before life emerged, is all I'm saying.

I agree and natural selection used chirality as a template to avoid the development of two left hands an two left feet .

The two forms of a chiral molecule, called enantiomers, have identical physical and chemical properties, but they manner in which each interacts with other chiral molecules may be different, just as a left hand interacts differently with left- and right-hand gloves.

Chiral molecules in living organisms in Nature exist almost exclusively as single enantiomers, a property that is critical for molecular recognition and replication processes and would thus seem to be a prerequisite for the origin of life. Yet left and right-handed molecules of a compound will form in equal amounts (a racemic mixture) when we synthesize them in the laboratory in the absence of some type of directing template.

The fact of the single chirality of biological molecules—exclusively left-handed amino acids and right-handed sugars—presents us with two questions: First, what served as the original template for biasing production of one enantiomer over the other in the chemically austere, and presumably racemic, environment of the prebiotic world? And second, how was this bias sustained and propagated to give us the biological world of single chirality that surrounds us?

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2857173/#:

 

[Q-reeus]

If it took months and miles instead of minutes and micrometers to duplicate something, that was ok - nothing was stopping it.

Except the inevitable presence of a whole lot of other reactive molecular species that would sabotage the hopeful self-replicator, terminating the (hypothetical) self-replication with essentially 100% probability.

 

[Q-reeus]

The notion of "irreducible complexity" has been debunked, not just scientifically , but in a Court of Law, based on the evidence presented . (See the Kitzmiller v Dover Trial)

That a particular judge ruled irreducible complexity to be 'unsupported by the evidence' speaks more for the prejudices and likely political pressure involved.
If you really want to know the truth on that subject, try starting here :

Don't pursue this here - the thread topic is prebiological chemical evolution. Keep on topic!

 

[paddoboy]

If you understand abiogenesis so clearly, then why are you compelled to introduce "evolution" into the equation?
You seem to be conflating an unexplained hypothesis, abiogenesis - life from non-life, and an actual scientific theory that begins with the premise that life already exists.

In actual fact, it appears to be you, q-reeus and the religiously fanatical Tour, that's conflating the unsupported myth of ID with the logic of extrapolation back to the obvious...Abiogenesis.

In Tour's own words, even if direct evidence of the methodology of Abiogenesis, was validated, it would not deter his fanatical faith in the word of the bible, and the nonsense therein.
He is a fraud and a charlatan, that has achieved two well known ID advocates on this forum.

 

[paddoboy]

That a particular judge ruled irreducible complexity to be 'unsupported by the evidence' speaks more for the prejudices and likely political pressure involved.
If you really want to know the truth on that subject, try starting here :

And the unsupported excuses and conspiracies continue!
Hallelujah and Amen!!

 

[Q-reeus]

In actual fact, it appears to be you, q-reeus and the religiously fanatical Tour, that's conflating the unsupported myth of ID with the logic of extrapolation back to the obvious...Abiogenesis.

In Tour's own words, even if direct evidence of the methodology of Abiogenesis, was validated, it would not deter his fanatical faith in the word of the bible, and the nonsense therein.
He is a fraud and a charlatan, that has achieved two well known ID advocates on this forum.

You hurl these spiteful accusations at Tour as if there was factuality behind them. No, it's just paddoboy doing his usual thing - substituting invective for objective facts.
Tour's religious convictions (what I referred to as compartmentalized thinking) are cleanly separated from his brilliant critiques of unguided abiogenesis hypothesis.

 

[paddoboy]

You hurl these spiteful accusations at Tour as if there was factuality behind them. No, it's just paddoboy doing his usual thing - substituting invective for objective facts.

Not really, in fact all of the reputable mainstream knowledgable scientists, have shown him to be a charlatan, a sample as I have previously given.....perhaps you need remove your blindfold?

Here is another interesting video.....Please, please, please!!! listen particularly from the 1 minute 30 second mark, to gauge the agenda that this James Tour is saddled with,,,,amazing!!! such gaul!!!

and..............

Here's another video of James Tour evangelizing about the Resurrection, and the "structure of the scriptures"
Let me say that what James believes is his business, and whether he follows and puts faith in Jesus and the bible is also his business.
What the last two videos show is that this man obviously, and despite his recognised expertise in chemistry, does have an agenda...in fact his words, reveal a fanatical agenda to put it mildly.

and this little doozy

Here is a critique of Tour's claims by Larry Moran: He is a Professor Emeritus in the Department of Biochemistry at the University of Toronto. You can contact him by looking up his email address on the University of Toronto website.

https://sandwalk.blogspot.com/2014/03/a-chemist-who-doesnt-understand.html

A chemist who doesn't understand evolution
James Tour is an organic chemist. He is a Professor of Chemistry and Professor, Professor of Mechanical Engineering & Materials Science, and Professor of Computer Science at Rice University (Houston, United States). James Tour is attracting a lot of attention on the Intelligent Design Creationist websites because he is sympathetic to their main claim; namely, that evolution is wrong [see A world-famous chemist tells the truth: there’s no scientist alive today who understands macroevolution].

Tour is one of the few genuine scientists who signed the Discovery Institute’s "A Scientific Dissent from Darwinism" (2001) that stated, "We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged." (There are very,very, few biologists who signed.)
more at link...................

the article concludes thus..............................
Ignorance is curable. If that's the only problem facing James Tour then he could do no better than read Stephen Jay Gould if he really wants to understand macroevolution. He will get a heavy dose of "pondering and thoughtfulness." I don't think he's up to it. I don't think he really wants to learn.

Here's why I don't think he really wants to learn about evolution.
James Tour said................
"What a comfort it must be to be pleasantly settled in one camp or the other, but I can not be so settled, and hence I have few tent-fellows. Based upon my faith in the Scriptures, I do believe (yes, faith and belief go beyond scientific evidence for this scientist) that God created the heavens and the earth and all that dwell therein, including a man named Adam and a woman named Eve. As for many of the details and the time-spans, I personally become less clear. Some may ask, What’s “less clear” about the text that reads, “For in six days the Lord made the heavens and the earth”? That is a fair question, and I wish I had an answer that would satisfy them. But I do not because I remain less clear.

I hope that’s satisfactory; I mean for me, a scientist and a Christian, to be unsure of a few things in both science and Christianity. The question is not fundamental to my salvation as a Christian which is based upon the finished work of Jesus Christ, my confession in him as Savior and my belief in his resurrection from the dead. And I used to think that my outward confession of skepticism regarding Darwinian Theory was also of little consequence to my career as a scientist. Specifically, in the past, I wrote that my standing as a scientist was “based primarily upon my scholarly peer-reviewed publications.” I no longer believe that, however.

In the last few years I have seen a saddening progression at several institutions. I have witnessed unfair treatment upon scientists that do not accept macroevolutionary arguments and for their having signed the above-referenced statement regarding the examination of Darwinism. (I will comment no further regarding the specifics of the actions taken upon the skeptics; I love and honor my colleagues too much for that.) I never thought that science would have evolved like this....

Hence, by my observation, the unfair treatment upon the skeptics of macroevolution has not come from the administration level. But my recent advice to my graduate students has been direct and revealing: If you disagree with Darwinian Theory, keep it to yourselves if you value your careers, unless, of course, you’re one of those champions for proclamation; I know that that fire exists in some, so be ready for lead-ridden limbs. But if the scientific community has taken these shots at senior faculty, it will not be comfortable for the young non-conformist. When the power-holders permit no contrary discussion, can a vibrant academy be maintained? Is there a University (unity in diversity)? For the United States, I pray that the scientific community and the National Academy in particular will investigate the disenfranchisement that is manifest upon some of their own, and thereby address the inequity."


I suppose I'm going to be labeled as one of those evil "Darwinists" who won't tolerate anyone who disagrees with me about evolution.1

I'm actually not. I just don't like stupid people who think they are experts in evolution when they have never bothered to learn about it. Here's my advice to graduate students in organic chemistry: if you want to know about evolution then take a course or read a textbook. And remember, there's nothing wrong with admitting that you don't understand a subject. Just don't assume your own ignorance means that all the experts in the subject are wrong too.

Tour's religious convictions (what I referred to as compartmentalized thinking) are cleanly separated from his brilliant critiques of unguided abiogenesis hypothesis.

Nonsense...he separates his religious/ID crap, about as much as you seem to do.
You and he are pushing shit up hill...

 

[Q-reeus]

Not really, in fact all of the reputable mainstream knowledgable scientists, have shown him to be a charlatan, a sample as I have previously given.....perhaps you need remove your blindfold?



and..............


and this little doozy


Nonsense...he separates his religious/ID crap, about as much as you seem to do.
You and he are pushing shit up hill...

paddoboy does what he always does - repeat post cut'n'paste from old links ad nauseum. Larry Moran's piece is notable for it's complete avoidance of Tour's strong suite which is critiquing unguided abiogenesis hypothesis. Tour was lured into commenting on post abiogenisis evolutionary theory which area is best left to true experts in that field notably Michael Behe. See my link in #69.

 

[paddoboy]

paddoboy does what he always does - repeat post old links ad nauseum. Larry Moran's piece is notable for it's complete avoidance of Tour's strong suite which is critiquing unguided abiogenesis hypothesis.

And you have done what you do best...fabricating conspiracies with blindfold precision to support any god bothering fanatic if he happens to have a few letters after his name, and ignoring the multitude that have refuted him.

Tour was lured into commenting on post abiogenisis evolutionary theory which area is best left to true experts in that field notably Michael Behe. See my link in #69.

excuses, conspiracies, unsupported fabricated claims, and more conspiracies.
Abiogenesis happened...that is certain. How? we have yet to properly figure out. Once there was no life: then there was.
We have absolutely nothing to point to some unscientific mythical proposition, just to create a warm inner glow of security in some.

 

[Q-reeus]

And you have done what you do best...fabricating conspiracies with blindfold precision to support any god bothering fanatic if he happens to have a few letters after his name, and ignoring the multitude that have refuted him.

excuses, conspiracies, unsupported fabricated claims, and more conspiracies.
Abiogenesis happened...that is certain. How? we have yet to properly figure out. Once there was no life: then there was.
We have absolutely nothing to point to some unscientific mythical proposition, just to create a warm inner glow of security in some.

So you keep asserting, padded with the usual assortment of totally unwarranted pejoratives and wild accusations. Classic paddoboy. Shout the loudest and longest and that is somehow winning the argument. No.

 

[paddoboy]

So you keep asserting, padded with the usual assortment of totally unwarranted pejoratives and wild accusations. Classic paddoboy. Shout the loudest and longest and that is somehow winning the argument. No.

I don't need to win the argument q-reeus. It's already won, and imo will only grow in certainty.
It's you [supported by you know who] shouting and screaming with regards to a scientific article in the OP, that validates chemical evolution. And who do you raise? James Tour! a religious fanatic, who takes the bible literally and even admits he would not stray from his so called rightous path, guided by the bible, no matter what the evidence for Abiogenesis. So much for your false adoration of this turkey.

 

[Q-reeus]

I don't need to win the argument q-reeus. It's already won, and imo will only grow in certainty.
It's you [supported by you know who] shouting and screaming with regards to a scientific article in the OP, that validates chemical evolution. And who do you raise? James Tour! a religious fanatic, who takes the bible literally and even admits he would not stray from his so called rightous path, guided by the bible, no matter what the evidence for Abiogenesis. So much for your false adoration of this turkey.

So, you are an atheist fanatic. Lovingly wedded so we are told to someone who is a bible-believing Christian. Be careful when throwing stones in a glasshouse.

 

[paddoboy]

So, you are an atheist fanatic.

Whatever floats your boat q-reeus...If refusing to be gullible and taken in by frauds is being an Atheist, that's OK with me. That at this time, aligns with the science.

Lovingly wedded so we are told to someone who is a bible-believing Christian. Be careful when throwing stones in a glasshouse.

Yep, she though generally keeps here beliefs to herself and I have no qualms about her bring her religious friends and choir over. It's called tolerance q-reeus. No glasshouse in sight nore stones my friend. Our Son though thankfully, leans my way.


ps: I don't tell dirty jokes or swear in front of her though.

 

[Write4U]

That a particular judge ruled irreducible complexity to be 'unsupported by the evidence' speaks more for the prejudices and likely political pressure involved.
If you really want to know the truth on that subject, try starting here :

Don't pursue this here - the thread topic is prebiological chemical evolution. Keep on topic!

Obviously you have not studied the Court Case, and that forces you now to cast aspersions on the ability of a judge to impartially weigh the evidence presented, in order to prove your totally misguided understanding of a totally scientifically "DEBUNKED" charlatan, Behe.

I won't pursue it here but you may want to peruse s0me of the 1790 posts devoted to the role and evolution of micro-tubules and the "flagella". (see Is consciousness to be found in quantum processes in microtubules? )