443.8–419.2 million years ago
Přídolí Series: 423.0±2.3–419.2±3.2 Ma
Ludlow Series: 427.4–423.0 Ma
Wenlock Series: 433.4–427.4 Ma
Llandovery Series: 443.8–433.4 Ma
What happened during this time?
The climate changes dramatically during this Period
The early Silurian was a time of global ice-house climate that included great ice sheets at high latitudes
During the middle of Llandovery the climate becomes warmer
The world during this time has distinct north-south climatic zones
Plate tectonic activity shifts continents
Gondwana drifted farther across the South Pole
Siberia, Laurentia, and Baltica clustered around the equator.
Laurentia and Baltica collided at the end of the Silurian, forming a new supercontinent, Euramerica, and raising new mountain ranges.
Formation of extensive evaporite (salt) deposits near the equator.
Large glacier melt and sea levels rise
Nearly continuous sea from New York to Nevada, and other shallow seas still covered parts of other continents
Mean oxygen levels in the atmosphere: 19%
Mean carbon dioxide levels in the atmosphere: 4,600 ppm
The earliest record of fire on Earth from 430 Ma (Glasspool & Gastaldo 2022)
Bryophytes diversify on landscape
The earliest polysporangiophyte macro-fossils found during Silurian
Diversification of land fungi
Coral reefs first appear
Relatives of spiders, scorpions, millipedes and centipedes first appear
The first flying insects probably appear during this time
Evolution of fishes; diversification of jawless fish