While we have discussed the connection between primitive coacervates and both membraneless organelles as well as as primitive cytoplasms, other types of modern biological structures could also be relevant to understanding primitive coacervates. One in particular are viruses, which we have discussed above in the context of their contribution to primitive nucleic acid-based systems and evolution (i.e., the RNA and DNA worlds). There are three generally accepted hypotheses on the origins of viruses themselves: regressive, escape theory, and virus-first. While we do not go into detail into these theories (please check the cited articles for more details), we do note that viruses are thought to be one of the earliest organisms to inhabit life on Earth, possibly predating the emergence of cells.