Mineral assemblages dating techniques smithsonian

Almost all the present phyla plants (Asterids - Verbena) appeared during this period, with the exception of Bryozoa, which are a phylum of aquatic invertebrate animals who made its earliest known appearance later, in the Lower Ordovician. First land plants occurs in the Ordovician, in the form of fossil spores.

Land plants began to diversify in the Late Silurian, from around 430 million years ago, and the results of their diversification are displayed in remarkable detail in an early Devonian fossil assemblage from the Rhynie chert.

A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 375–360 million years ago.

Overall, 19% of all families and 50% of all genera became extinct. Unicellular Organisms developed into Multicellular Organisms. Algae Dinosaurs Evolved and lived for 180 Million years (over 700 types).

Reionization marks the point at which the hydrogen in the Universe became ionized.

(3.9 Billion Years since the Birth of Earth, and 2.9 Billion Years since Microorganisms Formed)The earth was completely covered in Ice.

Snowball Earth Choanoflagellate are a group of free-living unicellular and colonial flagellate eukaryotes considered to be the closest living relatives of the animals.

This chert, formed in volcanic hot springs, preserved several species of early plants in cellular detail by petrification.

Paleozoic Timeline of Plant Evolution (wiki) - Photosynthesis Horseshoe Crab Living Fossil is an extant taxon that closely resembles organisms otherwise known only from the fossil record. Carboniferous is a geologic period and system that spans 60 million years from the end of the Devonian Period 358.9 million years ago (Mya), to the beginning of the Permian Period, 298.9 Mya. Hangenberg Event is a bioevent that occurred at the end of the Famennian epoch (late Devonian) associated with the Late Devonian extinction (roughly 358.9 ± 0.4 million years ago); Bioevent is an event recognised in a sequence of sedimentary rocks, where there is a significant change in the biota as recorded by assemblages of fossils over a relatively short period of time.

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Marine Biology , in the late Proterozoic, oxygen levels in the oceans and atmosphere increased dramatically.

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