Life is evolution, a dynamic continuum that has remained unbroken since its emergence. Traditionally, biological evolution is considered as a gradual process that consists essentially of natural selection, conducted through minimal phenotypic variations that are the result of genetic mutations and recombination to form new species. It is likewise a dynamic process that develops and responds not in the sense of perfection and progress, but in the sense of adapting to new conditions. However, evolution is not just the result of mutations and genetic recombination combined with natural selection. It involves other processes, namely symbiotic associations between different organisms to form consortia, a new structural life dimension and a symbiont-induced speciation, which have been secondary or even underestimated by the Neodarwinist approach. Symbiogenesis was introduced in 1909 by the Russian biologist Constantin Mereschkowsky and was defined as “the origin of organisms by the combination or association of two or more beings that enter into symbiosis”. It is an evolutionary mechanism that enables a coherent conceptual rupture in relation to evolutionary ideas of the past, but that simultaneously builds a new evolutionary approach to life on our planet. Symbiosis is therefore the vehicle through which the acquisition of new genomes and new metabolic and organismal capacities occurs, enabling the evolutionary construction of organisms. Given that symbiosis and synergies are fundamental patterns in nature, the presence of organisms living symbiotically and communicating with each other corresponds to the structural basis of evolutive success, as well as to a new level of hierarchical complexity organization in the web of life. Thus, the development of a Symbiogenic Theory of Evolution can contribute towards a new epistemological approach to the symbiotic phenomenon in evolution and towards new perspectives that allow for a better understanding of the web of life on Earth and beyond.