Epibolion

Epibolion is a term used in the field of biology to describe the process by which a single-celled organism, such as a protozoan, transforms into a multicellular organism. This process is often observed in the life cycle of certain organisms, where a single-celled stage, known as a zygote or a spore, develops into a multicellular form through a series of cell divisions and differentiation. Epibolion is a key mechanism in the evolution of multicellularity, as it allows for the formation of complex tissues and organs from a single cell. This process is particularly well-studied in the context of the evolution of animals, where it has been proposed that the transition from single-celled to multicellular life occurred multiple times independently. The term "epibolion" was coined by the biologist Ernst Haeckel in the 19th century, and it has since been used to describe various biological phenomena involving the transformation of single cells into multicellular organisms.