Dr Lynn Margulis, a biologist from Boston University, proposed in the 1960's, the theory of endosymbiosis. It was then officially published in her book "Symbiosis in Cell Evolution". The theory suggests that cells originated as communities of interacting entities a could join together in a specific order. Organelles like mitochondria and chloroplasts were themselves prokaryotic cells before the development of eukaryotic cells. It was believed that a host cell, probably similar to amoeba, ingested a smaller cell by phagocytes. …
