{Reference Type}: Journal Article {Title}: The bubble theory: exploring the transition from first replicators to cells and viruses in a landscape-based scenario. {Author}: Piast RW; {Journal}: Theory Biosci {Volume}: 143 {Issue}: 2 {Year}: 2024 Jun 9 {Factor}: 1.315 {DOI}: 10.1007/s12064-024-00417-4 {Abstract}: This study proposes a landscape-based scenario for the origin of viruses and cells, focusing on the adaptability of preexisting replicons from the RNP (ribonucleoprotein) world. The scenario postulates that life emerged in a subterranean "warm little pond" where organic matter accumulated, resulting in a prebiotic soup rich in nucleotides, amino acids, and lipids, which served as nutrients for the first self-replicating entities. Over time, the RNA world, followed by the RNP world, came into existence. Replicators/replicons, along with the nutritious soup from the pond, were washed out into the river and diluted. Lipid bubbles, enclosing organic matter, provided the last suitable environment for replicons to replicate. Two survival strategies emerged under these conditions: cell-like structures that obtained nutrients by merging with new bubbles, and virus-like entities that developed various techniques to transmit themselves to fresh bubbles. The presented hypothesis provides the possibility for the common origin of cells and viruses on rocky worlds hosting liquid water, like Earth.