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the_j4k3 t1_j8gswms wrote

I think anything novel must compete with well adapted, established organisms using a limited set of resources that the existing organisms recognize as food.

I believe there must have been more than one abiogenesis in the beginning, but only one was ultimately successful. Kinda like how there were many branches of Homo, but we are the only ones still around. I can't picture a scenario where one chance encounter leads to life as we know it. I can picture a situation where the conditions were conducive for life, many were nearly there, several would be defined as life now, and only one found success and dominated.

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SignalDifficult5061 t1_j8h46gb wrote

It isn't clear that there was a specific entity that could be widely considered alive that suddenly appeared one day at all.

There could have been millions of years of complex processes going on which was sort of a gradient from "definitely not alive" to "definitely alive".

Microbes can accept genetic information much more readily than animals do with unrelated forms, and all sorts of genes have probably disappeared in the last billion years. How would one define not ancestral to modern life vs ancestral.

Even if all the genes of some creature are no longer extant, they could arguably have shaped the evolution of genes that still are,so there is still some remaining influence.

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[deleted] t1_j8h5l8k wrote

[deleted]

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Ameisen t1_j8hgf75 wrote

Viruses require, by definition, host replication machinery to reproduce. They are completely inert otherwise. So... they could not have come first... or at least, not vira as we currently understand them.

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Demoralizer13243 t1_j8l09ia wrote

What suggests that there was not just a single but many a-biogenesis events. What makes you favor that over a single one other than that it could be possible?

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