A splendid video about evolution

I'm more wary of ID but I do think Cosmic Fine Tuning is a reasonably strong argument for Design especially when paired with the …

I share your assessment of cosmic fine-tuning: it’s not easy to explain away. It’s akin to asking “Why is there something rather than nothing?”—utterly unfathomable. I’m less convinced by the DNA argument, which seems to rest on a greater number of assumptions that may or may not hold and are hard to assess (like the assumption that every mutation is random which there really is no reason to believe) especially given that the entire process purportedly unfolded over billions of years.

I’m less convinced by the DNA argument, which seems to rest on a greater number of assumptions that may or may not hold and are hard to assess (like the assumption that every mutation is random which there really is no reason to believe) especially given that the entire process purportedly unfolded over billions of years.

Well do you realise what you are saying? I mean science has relied on Darwinian evolution (RM+NS) since the century before last. Now you are doubting its importance!

Can you flesh out - even approximately - the kind of mechanism that you envisage might produce DNA (or RNA) that could encode a protein with 200 amino acids (say) given that most of the steps can't be driven by RM+NS because even if the D(R)NA is transcribed, the resultant protein will not be useful, and so can't be selected. Think particularly about the fact that proteins may no longer fold correctly - meaning that the active site of an almost complete enzyme (say) may be destroyed and totally ineffective.

One of the things that James Tour - a fantastically creative organic chemist - has pointed out is that random chemistry, random DNA, or other random polymers, are simply impractical. This is because the monomers can polymerise in multiple different different ways. Just getting the bits together to get one cell working, would be impossibly unlikely.

In particular, all the main biopolymers are made of all one optical isomer or other - never a mixture of the two. This is hard to envisage if we think of the very first cell to be produced - because without life, most of the monomers would be produced in equal amounts (left and right).

David

Well do you realise what you are saying? I mean science has relied on Darwinian evolution (RM+NS) since the century before last. Now you are doubting its importance!

Can you flesh out - even approximately - the kind of mechanism that you envisage might produce DNA (or RNA) that could encode a protein with 200 amino acids (say) given that most of the steps can't be driven by RM+NS because even if the D(R)NA is transcribed, the resultant protein will not be useful, and so can't be selected. Think particularly about the fact that proteins may no longer fold correctly - meaning that the active site of an almost complete enzyme (say) may be destroyed and totally ineffective.

One of the things that James Tour - a fantastically creative organic chemist - has pointed out is that random chemistry, random DNA, or other random polymers, are simply impractical. This is because the monomers can polymerise in multiple different different ways. Just getting the bits together to get one cell working, would be impossibly unlikely.

In particular, all the main biopolymers are made of all one optical isomer or other - never a mixture of the two. This is hard to envisage if we think of the very first cell to be produced - because without life, most of the monomers would be produced in equal amounts (left and right).

David

Not @sbu but for me at least I just find it very hard to determine what is and is not reasonable to expect regarding the "waiting time" problem.

Even Dembski talks about stuff like an impersonal telic process which doesn't sound like Design to me?

To be clear I lean toward Design regarding Cosmic Fine Tuning and certain philosophical arguments like the Mystery of Psycho-Physical Harmony, but ID for me still seems questionable. This isn't to say I fully agree with their opponents either, or ascribe to some "Third Way" idea...just that I get lost trying to keep track of what these arguments are saying at times...

[Laird]

ID for me still seems questionable. This isn't to say I fully agree with their opponents either, or ascribe to some "Third Way" idea...just that I get lost trying to keep track of what these arguments are saying at times...

What was your final conclusion about Professor Dave's critique of ID and defence of mainstream evolutionary theory + abiogenesis? You put a lot of work into summarising and examining it, so I hope you have a takeaway for your own sake if nobody else's.

Well do you realise what you are saying? I mean science has relied on Darwinian evolution (RM+NS) since the century before last. Now you are doubting its importance!

Can you flesh out - even approximately - the kind of mechanism that you envisage might produce DNA (or RNA) that could encode a protein with 200 amino acids (say) given that most of the steps can't be driven by RM+NS because even if the D(R)NA is transcribed, the resultant protein will not be useful, and so can't be selected. Think particularly about the fact that proteins may no longer fold correctly - meaning that the active site of an almost complete enzyme (say) may be destroyed and totally ineffective.

One of the things that James Tour - a fantastically creative organic chemist - has pointed out is that random chemistry, random DNA, or other random polymers, are simply impractical. This is because the monomers can polymerise in multiple different different ways. Just getting the bits together to get one cell working, would be impossibly unlikely.

In particular, all the main biopolymers are made of all one optical isomer or other - never a mixture of the two. This is hard to envisage if we think of the very first cell to be produced - because without life, most of the monomers would be produced in equal amounts (left and right).

David

I think the key point is that any unobserved process that has been unfolding over billions of years has a lot of room for a being explained by naturalistic causes even though we yet can’t fit all the pieces. For example regarding the optical isomers, even if primordial chemistry produced a pre-cell with a mix of L- and D-isomers, that isn’t a fundamental barrier. Repeated experiments show that biological homochirality can emerge by purely chemical means, as long as there’s an autocatalytic reaction to amplify even the tiniest initial bias—whether it comes from polarized light, mineral surfaces, crystal templates, or sheer chance. In other words, it only takes a very small nudge to tip the system toward the uniform handedness we observe in life’s biopolymers today.

See for example:

https://pmc.ncbi.nlm.nih.gov/articles/PM...A032540C21

or

https://pubmed.ncbi.nlm.nih.gov/30853700/

What was your final conclusion about Professor Dave's critique of ID and defence of mainstream evolutionary theory + abiogenesis? You put a lot of work into summarising and examining it, so I hope you have a takeaway for your own sake if nobody else's.

Ah I still need to finish going through those articles and rebuttals, thanks for the reminder!

I think the key point is that any unobserved process that has been unfolding over billions of years has a lot of room for a being explained by naturalistic causes even though we yet can’t fit all the pieces. For example regarding the optical isomers, even if primordial chemistry produced a pre-cell with a mix of L- and D-isomers, that isn’t a fundamental barrier. Repeated experiments show that biological homochirality can emerge by purely chemical means, as long as there’s an autocatalytic reaction to amplify even the tiniest initial bias—whether it comes from polarized light, mineral surfaces, crystal templates, or sheer chance. In other words, it only takes a very small nudge to tip the system toward the uniform handedness we observe in life’s biopolymers today.

See for example:

https://pmc.ncbi.nlm.nih.gov/articles/PM...A032540C21

or

https://pubmed.ncbi.nlm.nih.gov/30853700/

The problem with this is that there is no evidence that "naturalistic" causes can even begin to explain the observed complexity of structures. Darwinians do not know ~ they presume that their brand of Evolution was responsible, and then base everything around that, even if it has to mean created rather convoluted "explanations" that they push as "factual".

In reality, no-one has a clue where life came from. But the complexity is enough to make even the most talented human engineer blush fiercely. That's a clue that life is no accident of non-conscious physical processes, but something far more than we can comprehend.

[primer]

First I'd like to ensure everyone understands the issue here. A pair of isomers are two molecules in which the atoms are arranged differently in some way. For example ethanol is an isomer of dimethyl ether - they both have the formula C2H6O.

A particularly subtle kind of pairs of isomers, is one in which the connections are the same, but the two isomers are mirror images of each other - just as a pair of gloves differ from each other. These are known as optical isomers for basically historical reasons.

A chemical reaction with optically inactive starting materials won't create an optically active product. However it may produce a 50:50 mixture of optically active molecules - known as a racemic mixture.
[/primer]

For example regarding the optical isomers, even if primordial chemistry produced a pre-cell with a mix of L- and D-isomers, that isn’t a fundamental barrier.

Yes, but what you seem to fail to realise that the monomers come in L and D forms, but that shape of a polymer is going to be hugely affected by the distribution of L and D components down the chain.

In the case of DNA this would result in something that could not coil up. In the case of proteins, well proteins depend on folding in a consistent way. If the folding is disrupted by a distribution of L and D isomers on its chain the protein product will be worthless.

The two papers that you refer to only solve the simpler problem of reproducing the fact that life only uses L or D chemicals as appropriate. I had always assumed that this problem would solve itself after the first cell appeared because all future life would consist of the daughters of that first cell.

James Tour hardly spoke on that video, but he really has studied the concept of a-biogenic synthesis of the chemicals of life, though unfortunately he can't resist the temptation to insert a bit of bible bashing into his talks! In particular, JT repeatedly points out that other researchers will run a reaction A->B (say) and then buy pure B and maybe perform a reaction B->C. Then they will claim that A can be converted to  on the Earth before life began.

However, many of these reactions only work to a certain degree, so after performing A->B (say), it is necessary to perform an elaborate purification step before going on to make C. Without this step you will probably obtain something organic chemists refer to as 'tar'.

In a prebiotic Earth it is reasonable to assume that a lot of 'tar' will be lying around.

Note that all this is before we consider how useful information is encoded in DNA (a protein blueprint say).

David