Plant Evolution PP

Modern day plants diverged from many lineages which began with the event of endosymbiosis. Endosymbiosis is the act of an organism engulfing of an organism and living inside the other. In modern day plants, this commenced with the primary endosymbiotic event involving cyanobacteria. Cyanobacteria is a photosynthetic blue-green. Though the earliest forms of cyanobacteria did not produce O2, eventually they began to oxidize. For plants to evolve, a eukaryotic cell engulfed the cyanobacteria and degenerated into a chloroplast. After this event, a second endosymbiosis event occurred that diverged into red and green algae and thus their divergents. Without these endosymbiotic events, the ancestors of plants would not have been able to evolve into what they are today.