Code as an Analogy of DNA?

Science

(S. Joshua Swamidass) #302

I have conversed with him recently. The situation is far less definitive than either side would have you believe.


(Dale Cutler) #303

Hmm. Okay then. Someone is missing something, and it’s not me.


(Timothy Horton) #304

Dr. Tour doesn’t work on and shows virtually zero understanding or knowledge of abiogenesis research. His opinion on the topic carries as much gravitas as any uninformed layman.


(Dale Cutler) #305

In your humble opinion.


(Timothy Horton) #306

Dr. Swamidass is correct in that DNA is not a code by the definition you insist on.


(Dale Cutler) #307

What definition, exactly, was I insisting on. A process for storing information in memory. Oh dear. I totally recant.


(Timothy Horton) #308

In mainstream science’s opinion. Tour produces ID propaganda for the DI. It’s worth as much as the paper it’s printed on.


(Dale Cutler) #309

You philosophical prejudice is showing.


(Timothy Horton) #310

Your scientific illiteracy has shown for some time.


(Dale Cutler) #311

I’m okay with that. We’ll see what truth reveals.


(John Mercer) #312

There is the testing of the hypothesis that the “code” is arbitrary…


(Mikkel R.) #313

No, not evidence that “abiogenesis evolved”. I don’t even know what that means. Abiogenesis is “the origin of life from non-life”.

What I said there was evidence of is that abiogenesis was a natural process. As in evidence it was a process governed by the known laws of physics and chemistry.

There is in fact evidence (not unassailable proof, but evidence nonetheless) that the origin of life was a process governed by the laws of physics and chemistry, as opposed to some sort of intelligent design. The inferred amino acid frequencies in the ancestors of the oldest known proteins correlate increasingly with the distribution of amino acids produced in abiotic chemical reactions, and predicted to result from them by thermodynamics, as we go further and further back in time when infering ancestral sequences. The closer we get to life’s origin, the more the protein sequences contain the kinds of amino acids that would have been produced non-biologically in abiotic chemistry, and therefore contain fewer and fewer instances of the “modern” amino acids such as Tryptophane.

This is what one would expect if life originated by a blind, unguided physical and chemical process whereby the first proteins were synthesized by polymerization of the sorts of amino acids that existed in the prebiotic environment, instead of being somehow intelligently designed and manufactured by an intelligent chemist that had access to a greater repertoire of amino acids than mere geochemistry can produce and could cause particular chemical reactions to occur at will.

See for example:
Higgs PG, Pudritz RE. A thermodynamic basis for prebiotic amino acid synthesis and the nature of the first genetic code. Astrobiology. 2009 Jun;9(5):483-90. [DOI: 10.1089/ast.2008.0280]

Trifonov EN. Consensus temporal order of amino acids and evolution of the triplet code. Gene. 2000 Dec 30;261(1):139-51. [PMID: 11164045 ]

Brooks DJ, Fresco JR, Lesk AM, Singh M. Evolution of amino acid frequencies in proteins over deep time: inferred order of introduction of amino acids into the genetic code. Mol Biol Evol. 2002 Oct;19(10):1645-55. [PMID: 12270892]

This is evidence for a physics/chemistry-based origin of life, and evidence against rational intelligent design, because an intelligent designer could simply have designed a modern bacterium with the complete biochemical pathways for making all 20 extant amino acids, ensuring it’s capacity to adapt to future environmental challenges.

You have not conversed with Dr. Tour lately.

I don’t care about James Tour, his words don’t dictate reality.


(Dale Cutler) #314

I used scare quotes because that’s what you said.


(Dale Cutler) #315

Why then do some appeal to panspermia of the gaps, even declaring it a new paradigm?

Progress in Biophysics and Molecular Biology
Volume 136, August 2018, Pages 3-23
Progress in Biophysics and Molecular Biology
Cause of Cambrian Explosion - Terrestrial or Cosmic?


(Mikkel R.) #316

Fair enough. I’ll drop that one as it’s an unimportant point, I do think we know what each of us meant to say.


(Mikkel R.) #317

Because they’re nuts? Wickramasinghe is impressively confused and gullible and has this ludicrous idea he can’t let go of. He once found diatoms in high-altitude aerosols and think they came from outer space and seeded life on Earth. Then he published it in his own ridiculous vanity journal (Journal Of Cosmology)* reviewed by himself.

When you see “Hoyle-Wickramasinghe”, your rule of thumb should be to distrust it.

*Click on the link, be amazed at how silly it is.


(Dale Cutler) #318

How does he get published?! :slightly_smiling_face:


(Dale Cutler) #319

That isn’t it, is it?


(Dale Cutler) #320

Ah, I didn’t see your addition. So I guess my question stands. :slightly_smiling_face:


(Mikkel R.) #321

Some times scientists publish a hypothesis. That doesn’t mean the journal editors or reviewers agree with the hypothesis, but it is common practice for journals to have a section devoted to yet-to-be-assessed hypotheses so scientists can get their ideas out there and spur experimentation and observation. It’s part of the process of science.

What can then happen later is that new observations are made, or new experiments are done, and rebuttal-papers can be published. So the literature can contain these really long back-and-forth arguments, with multiple experiments, hypotheses, reviews and so on, and eventually over time some scientific consensus can form.