Prebiotic chemistry: A call for open-mindedness
Origin-of-life research strives to answer the questions how and under which circumstances the first replicating life forms emerged. Investigating Reaching billions of years into the past, scientists rely heavily on extrapolation and assumptions to create a plausible scenario that could represent the environment on early Earth. So how can we investigate prebiotic chemistry?
The lack of definitive information about early Earth poses a big challenge for disciplines such as prebiotic chemistry research, which investigates the physical and chemical reactions that could have led to early replicator molecules. The opinions in the field of prebiotic chemistry diverge earlier than in many other physical science disciplines (at the stage of the experimental setup: Since direct evidence for what the environment at the origin of life was like is difficult to acquire (because it happened billions of years in the past), there is currently no unified answer to the question what experimental setup plausibly recreates the conditions on early Earth. Tightly controlled experimental conditions are a prerequisite to obtain reproducible and reliable scientific evidence that eventually confirms a hypothesis. But what if there is no certainty of the appropriate reaction conditions in the first place, let alone a suitable control? First and foremost, a chain of reactions yielding exactly the desired product shows that the molecule of interest can be obtained under the chosen experimental conditions. Therefore, the difference between a glimpse in the chemistry of the origin of life and chemistry depends on how we envision early Earth.
To facilitate exchange of ideas about this matter of dispute in prebiotic chemistry research, Nature Communications invited several experts in the field of prebiotic chemistry and related disciplines to share their opinion on how early Earth can be plausibly mimicked in the laboratory. Since this is a complex question, we narrowed it down to the essence of life by asking precisely: Which experimental conditions should be chosen when designing an experiment to investigate the origin of genetic material (nucleic acids)?
Several experts decided not to participate because of the feeling that the direct adjacency and inadvertent comparison to other opinions would put their piece into an unfavourable light. Each of the eight comments commissioned expresses an individual opinion. However, most of our contributors advocate maintaining an open mind with regard to plausibility: Since we are unlikely to obtain a clear image of early Earth and its environment in the near future, we cannot possibly exclude any concept. In the end, it is a question of likelihood and what fits best in the picture related scientific disciplines like astrophysics, microbiology, and geosciences and their data have created.
The comments can be found here, embedded in a collection on the chemistry of early Earth. While opinionated, the comments transfer a clear message: Let’s keep an open mind and let’s discuss! We editors are keen to participate, so please comment and share your opinion.
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