The RNA world! It's a theory that before there were proteins or DNA, there was what is commonly thought of as the intermediary stage between the two - RNA. It's a theory of abiogenisis by which life came about in a primordial soup animated by lightning strikes until an organic molecule occurred. Then, by time one molecule began to replicate itself, it was the most likely to occur over time and the rest is history. I'm always very thankful that I took a detour in my degree in MKUltra-ing to take a virology class. I learned about RNA in depth before I got exposed to people talking about mRNA in the context of being anti-vaxx like they know shit about fuck.

https://en.wikipedia.org/wiki/RNA_world