More than eighty years ago, before much was understood about the structure of cells, Russian botanist Boris Kozo-Polyansky outlined the concept of symbiogenesis, the symbiotic origin of cells with nuclei. It was a half-century later, only when experimental approaches that Kozo-Polyansky lacked were applied to his hypotheses, that scientists began to accept his view that symbiogenesis could be united with Darwin's concept of natural selection to explain the evolution of life.
After decades of neglect, ridicule and intellectual abuse, Kozo-Polyansky's ideas are now endorsed by virtually all biologists. His seminal work is presented here for the first time in an annotated translation, updated with commentaries, references and modern micrographs of symbiotic phenomena.