Wednesday 10 October 2018

evolution - How did the first self replicating organism come into existence?


When people try to explain evolution, they tell me that evolution is a cumulative result of mutations & natural section of the more superior individuals of a particular species. I think I'm fairly convinced with this explanation.


But when I think about it, all of them assume that there was an organism, however simple, that was capable of self replication & occasionally mutate. How did such an organism come into existence? Can anyone explain this?


An answer I found on Reddit didn’t really convince me.




Answer



Evolution or (as Darwin called it) "descent with modification" is a theory which explains the origin of the species NOT the origin of life. How the first life arose is completely irrelevant to the theory of evolution. What evolution does explain is how and why we have such variety of life on earth all descending from the same organism.


What you're asking about is not a theory of "evolution" but rather a theory of "abiogenesis." Although there are many interesting hypothesis for how abiogenesis happened (e.g. the RNA world, the "metabolism first" theory, etc.), the fact is we simply do not know yet how life first arose. What we do know is that life first arose between 3.5 and 3.9 billion years ago. That's a really long time ago compared to lots of other important events in natural history (even the Cambrian explosion where modern animal phyla evolved was only half a billion years ago), and so it shouldn't be surprising that it's a hard problem.


No comments:

Post a Comment

evolution - Are there any multicellular forms of life which exist without consuming other forms of life in some manner?

The title is the question. If additional specificity is needed I will add clarification here. Are there any multicellular forms of life whic...