So you want to find that special thing that replicates best and lasts longest? Just vibrate a bunch of molecules a long time!

You might reasonably assume that molecules wouldn't practically ever randomly assemble themselves into anything worth looking at. It happens a bit differently instead:

1. Eventually, "solar systems" will form. Each one has an independent star (energy source) with several independent planets (experiment boxes) that vary in their temperature, mass, composition, etc dramatically. (Instead of just having a big homogenous soup throughout the universe with much less search power)

• these planets will conveniently have "continents" sometimes to run more independent experiments on each one

2. A lipid layer boundary innovation thing leads to trillions of independent chemical experiments on some planets (instead of a big soup within each planet)
3. A general protein factory is discovered. Critically, it uses a simple and concise and robust physical encoding scheme. This allows good bubbles from step 2 to copy quickly and exactly, and clear out weak bubbles faster.
4. Very large multicellulared organisms make several search improvements: creatures can do sexual selection on each other instead of just getting random mutations; big smart fast predators can find & kill weak creatures quite effectively; parasites find weaknesses early & often. This all clears out weak replicators and leaves more room for the good ones.
5. Some creatures develop language and culture, which isn't generally much use, except that it one day allows them to design new replicators from scratch.

So you really can just vibrate sand and get out all kinds of things!

A bit misleading to talk about nature's great search as natural selection via mutations+generations. It's actually much weaker (there is no algorithm or optimizer at all, only one long aimless physics sim) or uh much stronger (a five-level hierarchy having branch factor ~ 1 billion of experiments of different kinds).