The Paleobiologic Record of Cyanobacterial Evolution

摘要: This chapter considers one of the broadest questions microbial evolutionary development, namely, what does paleobiological record suggest about tempo and mode prokaryotic, especially cyanobacterial evolution? By mid-1800s, when Darwin unveiled his grand theory, major features o f Phanerozoic history life, spanning most recent several hundred million years, had already been deciphered. late 1980s, these coalesced to produce first rRNA phylogenic trees, powerful new means decipher relations among organisms modern world. Microbial mat-building communities in such settings today are almost always dominated by members Oscillatoriaceae Chroococcaceae, same two families inferred be present environments during Precambrian. The isotopic compositions organic carbonate carbon Apex chert associated sedimentary units evidence occurrence photosynthetic CO2 fixation like that occurring extant populations grown -rich environments. Other issues have drawn less attention, them biotic interactions with long-term environmental change physiology biochemistry ancient fife. available geochemical data add support this interpretation and, known cellularly preserved fossils, presence other early-evolved prokaryotic lineages as well. Like concepts bradytely arrested evolution, inference rates is based on morphologic comparison fossils their living relatives. versatility cyanobacteria shown Chroococcaceae Oscillatoriaceae.