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8

I wouldn't go so far as to say that they are entirely unrelated -- our understanding of selective processes can certainly inform our study of the origin of life -- but I would say that they are quite different projects. One important reason is that evolutionary biologists can use phylogenetic information to reconstruct much of the history of life. For ...


7

Abiogenesis, the development of living things from non living matter, is not something we know much about, since it happened about 4 billion of years before we were around and haven't reproduced it in the lab. My guess is that it's not easy. However, the Miller-Urey experiment and others have told us something about abiogenic production of organic compounds. ...


4

It was getting long for a comment: A species that was originally parasitic, but then evolved to survive independently of its host by independently evolving the same metabolic functions A predator that originally relied on its prey to synthesise some vital metabolite, but later evolved the ability to produce the missing metabolite for ...


3

If you're willing to accept many orders of magnitude and define life as the Last Universal Common Ancestor. For the rest of this answer, life begins 3.5 Gya with cyanobacterial mats and stromatolites and so on. Genetically the LUCA is dated to around this time, which matches the fossil record and everything's great. The LUCA can't have sprung from ...


2

You are right in the sense the evolutionary biology doesn't try to explain the origin of life as it is not within its scope. Other fields of biology investigate the question of origin of life (abiogenesis). Now, there is a very important difference between spontaneous generation and evolution. Life originated at some point and the through repetitive ...


2

The problem with Intelligent Design is that it doesn't appreciate that the forces that shape species (and individual organism) have to be constant and ongoing or the species disappears. The past matters little, it's what happens right here, right now that keeps species in any particular form. Biological system are not static structures like a building. You ...


2

The main hypothesis is that all starts from RNA. "The RNA world". There was no DNA and no proteins. Both function was performed by RNA. Now there are no living organism that carrying information in RNA (only viruses...), but there is "enzymes" from RNA - ribozymes. The evolution to DNA was later, according to this hypothesis. There is really good article in ...


2

See this more as a comment than an answer, since it became too long for a comment. However, I think some of the examples should be relevant to refine your question. One thing that I find vague in this question is what exactly constitutes a "process"/"function"? To me, this can be almost anything. You seem to be focusing on molecular biology and biological ...


2

The E. coli long term evolution experiment showed that E. coli had evolved a function (the metabolism of citrate) which was not required in the ancestral environment, but which evolved naturally and was selected for in this new artificial environment. AFAIK, this is the only example of a function that has been observed naturally evolving under controlled ...


2

There are two questions here: Why does life only generate life? Why doesn't life continue to be generated on Earth? The first one is easy. We don't only generate life. If that were true, it might be illegal to flush toilets. Life forms of some kind would occupy all the space in our atmosphere. Babies - or some living things - would rise up from our ...


2

I think it's a mistake to assume that there is such a point. All plausible seeming models of abiogenesis currently under consideration involve evolutionary processes long before they reach the stage we'd consider alive. Evolution will occur whenever there is (a) replication-with-error and (b) selection (simplifying slightly). This is the case with a ...


1

Our understanding of how life began on earth has indeed advanced substantially since Haldane, Oparin, Miller, and Urey. To learn about the latest ideas, I can't think of a better place to start than this excellent video series with Nobel Laureate Jack Szostack, who is currently doing some of the leading work on the subject.


1

This question has actually been covered (although not to the complete extent of evolutionary history) by Richard Dawkins in his book The Ancestor's Tale. He gives the following estimates of LUCA time and generations: Monkeys and apes: 40MY(3M) Mammals: 180MY(120M) Reptiles: 310MY(170M) Ray finned fish: 440MY(195M) Sharks, hagfish and lampreys: ...


1

After considering this question some more, I think a key feature for this hypothesis to work is that the original function must be so integrated and vital for the biology of the organism that it must be mimicked/echoed to some extent. In terms of your RNA-example, it was not enought to evolve the ability to synthesize any complex molecule that could function ...


1

Evolution is about descent with modification. Spontaneous generation doesn't have that. It's about modern organisms emerging from raw molecules. If flies spontaneously appeared from rotting cow meat, why would they have DNA that made them look like they were evolutionarily related to other insects?



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