[JuliusPullo]

This should be easy to observe. If this process of creation of rich-complex molecules is happening today, we should be able to find some of these "ponds" where bacteria feeds on newly created rich molecules. If this found, then we would know why every bit of life on earth today descends from one single common ancestor (Last universal common ancestor)--The more complex of the first lifeforms to exist simply ate every other that arose afterwards.

[gus_massa]

The efficiency of these reactions is much less than photosynthesis, so don't expect to find this now.

Also, it probably requires an ambient with a lot of methane or some similar compound, but probably other bacteria are eating the methane, or oxygen is destroying it.