Silurian
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The Silurian is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at 443.1 Ma to the beginning of the Devonian Period, 419.62 Ma. The Silurian is the thir
Ordovician-Silurian boundary on Hovedøya, Norway: the brownish late Ordovician mudstone and later dark deep-water Silurian shale layers have been overturned by the Caledonian orogeny.
Fossils of the late Silurian sea bed, England
Diorama of a Silurian seafloor
Cooksonia, the earliest vascular plant, middle Silurian
Paleozoic
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The Paleozoic Era is the first of three geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago, it succeeds the Neoproterozoic and ends 251.9 Ma at the start of the Mesozoic Era. Th
Silurian
…Period, at 443.1 Ma (million years ago) to the beginning of the Devonian Period, 419.62 Ma. The Silurian is the third and shortest period of the Paleozoic Era, and the third of twelve periods of the Phanerozoic Eon. As with other geologic periods, the rock beds that define the period's start and end are…
Trilobites
Cephalaspis (a jawless fish)
Eogyrinus (an amphibian) of the Carboniferous
Life in the early Paleozoic