RNA evolved into a tiny loop that replicated faster

A closer look

Evolution usually favors complexity, but sometimes being dumb and fast is the superior survival strategy. In the 1960s, geneticist Sol Spiegelman put replicating RNA in a test tube. Without the need to build a protective cell or perform any actual biological work, the RNA ruthlessly deleted its own genes. It stripped itself down to a tiny 218-nucleotide loop, becoming a hyper-speed replicating parasite that completely dominated the test tube.