Theoretical origin of life: newest Darwinist critique (Introduction)

by David Turell @, Thursday, February 29, 2024, 21:20 (57 days ago) @ David Turell

Not from ID but sounds like it:

https://www.nature.com/articles/d41586-024-00544-4

"There is no consensus about what to look for, or where. Nor is there even agreement on whether all life must be carbon-based — although all known life on Earth is. Did meteorites deliver cells or organic material from outer space? Did life start on Earth in the hot waters of hydrothermal systems on land or in deep seas?

"Observations alone cannot constrain these possibilities. The few geological traces that hint at early life are enigmatic. Is a bacterium-like imprint really a fossil, or some geochemical structure? Is a weak carbon isotope signature on the surface of a mineral a fingerprint of life (which accumulates the lighter carbon-12) or the result of another type of chemical activity?

"Genes are not directly helpful either. Comparing gene sequences in modern organisms allows researchers to reconstruct a ‘tree of life’ going back to some of the earliest cells that have genes. Although the exact genetic make-up of this ancestral population is disputed, by definition it already had genes and proteins and so can tell us little about how they arose.

"None of this precludes understanding the origin of life, but it does make competing hypotheses hard to prove or disprove unambiguously. Combine that with the overarching importance of the question and it’s clear why the field is beset with over-claims and counter-claims, which in turn warp funding, attention and recognition.

"This context has splintered the field. Strongly opposed viewpoints have coexisted for decades over basic questions such as the source of energy and carbon, the need for light and whether selection acts on genes, chemical networks or cells.

"To understand how life might have begun, researchers must stop cherry-picking the most beautiful bits of data or the most apparently convincing isolated steps, and explore the implications of these deep differences in context. Depending on the starting point, each hypothesis has different testable predictions. For example, if life started in a warm pond on land, the succession of steps leading from prebiotic chemistry to cells with genes is surprisingly different from those that must be posited if the first cells emerged in deep-sea hydrothermal vents.

***

"On balance, we would say that prebiotic chemistry starting with cyanide can produce the building blocks of life, but most of the downstream steps predicted by this framework remain problematic.

***

"the hydrothermal scenario offers a promising route to the emergence of genetic information, overcoming Hoyle’s jumbo-jet argument. Patterns in the genetic code suggest direct physical interactions between amino acids and the nucleotides that encode them, especially for those formed most easily by metabolism5. Such associations mean that random RNA sequences could act as templates for non-random peptides that have a function in growing protocells. The first genes wouldn’t have had to encode metabolism, but just enhance flux through a spontaneous protometabolism — for example, by enabling the reaction between H2 and CO2.

"Thus, in short, the two frameworks have different advantages and disadvantages, and it is premature to dismiss either.

***

"If none of these scenarios is ‘wrong’, then there is space in the field to pursue multiple frameworks. No one needs to abandon their favoured positions (yet). But brash claims for a breakthrough on the origin of life are unhelpful noise if they do not come in the context of a wider framework. The problem is ultimately answerable only if the whole question is taken seriously. (my bold)

***

"The origins-of-life field faces the same problems with culture and incentives that afflict all of science — overselling ideas towards publication and funding, too little common ground between competing groups and perhaps too much pride: too strong an attachment to favoured scenarios, and too little willingness to be proved wrong. These incentives are amplified by the difficulty of disproving complex interrelated hypotheses involving different disciplines when there is so little direct evidence — no ‘smoking gun’ to be discovered.

***

"It is too soon to aim for consensus or unity, and the question is too big; the field needs constructive disunity. Embracing multiple rigorous frameworks for the origin of life, as we advocate here, will promote objectivity, cooperation and falsifiability — good science — while still enabling researchers to focus on what they care most about. Without that, science loses its sparkle and creativity, never more important than here. With it, the field might one day get close to an answer."

Comment: has the honest tone of James Tour, but isn't ID. Note my bold, the hype about each new tiny discovery is disgusting. What I have left out are long chemical discussions of each approach.


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