What Is the RNA World Hypothesis?

Evolution probably goes back before cells. The first living thing would have to be a self-replicating molecule that uses energy. Different forms of this self-replicating molecule would have different reproductive success. There is a not-unpopular theory that the original form of life on earth was an RNA molecule. RNA is a special molecule, because it can both act as a store of data, and as an enzyme for catalyzing reactions. According to this theory, specialized data storage in the form of DNA evolved later, along with specialized enzymes. Here's a brief overview of the theory that shows how evolution could happen with chains of RNA only: [VIDEO] Jack Szostak at Harvard has a great series of videos explaining this theory, and also a number of experiments that he and his students have performed. [LINK]

You may be looking for the RNA world hypothesis [1] [2]. In essence, random bits of RNA combine and replicate "in the wild". The bits that replicate better become more prevalent, et cetera, et cetera . This system needs no metabolic process per se . Heating and cooling and/or an oscillating chemical environment , e.g. from the day and night cycle or the tides or a belching vent, could provide the energy to power these cycles. [1] [LINK] [2] [VIDEO]

Stated Clearly has a great video about the RNA world hypothesis ( [VIDEO] ) if anyone's looking for an engaging overview.