古生物学-演化阶段

Micro-flora from Changzhougou Fm (Hebei，1.9 billion years ago）
Characters: relatively large in size (generally its diameter>40m，the maximum up to 300 m。
Fig Tree Group（ S. Africa， 3.1~3.2 billion years ）
Eobacterium isolatum （等称原始细菌）in black chert，with twolayer membrane (膜) structure, possibly with the earliest organ for photosynthesis. With chlorophyll (叶绿素) in it.
Eukaryota （真核生 物）:Animikiea、
Gunflintia、Eoastrion、
Kakabekia unabellata。 Bule algae flurished，they were major producers in sea。 Star-like algae， comparable with some present freshwater forms， indicating the salinity was about 5~10‰ in sea
Mc Minn Fm（N Australia， 1.4 billion years）
Characters: Spherical one-cell, there are some dense matters, which might be something like nuclei.
Bitter Springs Fm（Central Australia，0.9-1 billion years)
Fortescue Group（W Australia，2.8 billion years）
Silk-like prokarytoa in stromatolites （叠 层石），unbranched， with reproductive segments。Without nucleus。
Gunflint Formation（Canada， 1.95 billion years）
Late Precambrian Duoshantou phosphorites， with metazoan （multicellular animal，后生动物） embryos preserved in early cleavage stages
借助同步加速器辐射显微X线断层摄影术，科研人员重构了这种胚胎的三维图像
Bungle Bungle Dolomite（W Australia，1.6 billion years）
Characters： dominated by eukaryota （真核 生物，algae）， many leaf-like forms（a）。
At same time， with blue alage （prokaryota原核 生物（b-e）。
Warrawoona Group（W Australia， 3.5 billion years）
Characters: filamentlike or radiates, mono-cell spheres, belonging to bacteria. Such as Sulphurbacterium(琉细菌)、 Pigmented gliding bacteria（色素滑细 菌）、 Cyanobacteria （蓝细菌）
Characters: with real nucleus, cellwall and cytoplasm(细胞 质): Glenobotrydion aenigmatis (幽 葡萄藻 ）
Trace fossil of metazona （India，1 billion year）
Weng’an Fauna（Guizhou，600 million years）
Main stages of biological evolution
Evolutionary stages
Once the life appeared, it entered the stage of bioevolution, the chemical evolution was terminated. In the long process of life evolution, the biological evolution was step by step.
Wilpena Pound Fm（End of Precambrian，0.54 billion years ago），South Australia
Onverwacht Group（earliest life forms） （S. Africa， 3.5 billion years）
Archaeosphaeroides barbertonensis（巴 伯顿古球菌） （Proto-cell, 原细 胞？） (根据对碳氢化合物 的有机地球化学分 析)
生 命 演 化 的 阶 段 性
Big explosion
Free oxygen tion
Earliest fossil
records
Chemical evolution
Spider
Main stages
Nautilu s
Chimp -anzee
Crocodile
Fossil records of early life （早期生命的化石证据）
Occurrence of leaf-like forms, they are typical structures of lower plants.
With ecological diversity, which was prepared for adapting environmental change