I love this stuff.
“How did a bunch of lifeless molecules transform themselves into living cells, turning the ancient, dead Earth into a planet teeming with life? It's an incredibly difficult question to answer, but a new model might explain part of the story. Before you can have life, complex organic molecules have to start replicating themselves in much the same way that cells reproduce. Molecules that can replicate themselves using only the chemicals around them are what we might call "protocells", a key transitional stage between a fully lifeless world and one dominated by living cells. But explaining how protocells come to be has proven tricky. Even if scientists can come up with a mechanism by which the molecules can reproduce, the process always involves lots of copying errors, or mutations. The occasional mutation will be beneficial for the molecule and increase its ability to reproduce - a rather rudimentary form of evolution, if you will - but the vast majority of these errors are just that, mistakes that leave the molecules unable to replicate properly. There's decades worth of experiments showing that these bad mutations will eventually win out and make impossible any further replication.” Click here for more