Paleozoic Era 3: Silurian Period – Unsettled Conditions
Key Events
- Though relatively short, the Silurian Period is a time of volatile changes.
- Major extinction events are followed by life bouncing back.
- Fish develop moveable jaws, enabling new ways of feeding, and bony species of fish emerge.
- On land, small mosses and plants appear beside lakes, streams and coastlines.
- Millipedes and spider-like arachnids (spider-like) evolve.
![](https://cornwallseatostars.org.uk/wp-content/uploads/2023/07/Sea-to-Stars-Line-elements-A3-Finals_Page_06-2-724x1024.jpg)
Facts, Debates & Trivia
- The name comes from an ancient Welsh tribe, the Silures, who lived where rocks formed during this period are found.
- The change in sea-levels over the Silurian Period may beas much as 140 metres (taller than the Great Pyramid of Giza).
- Islands, reefs and warm, shallow seas provide environments where life can recover from extinctions caused by the changing conditions.
![](https://cornwallseatostars.org.uk/wp-content/uploads/2023/07/Cornwall-Sea-to-Stars-V5-Proofs_Page_07-341x1024.jpg)
Conditions
- The climate undergoes several dramatic fluctuations.
- High sea levels over relatively flat continents result in many island chains.
![](https://cornwallseatostars.org.uk/wp-content/uploads/2023/01/7-Silurian-430_million_ya-1024x883.jpg)
Timeline
443.8 – 419.2 million years ago
(26.4 million years)
![](https://cornwallseatostars.org.uk/wp-content/uploads/2023/01/7-Stopwatch-Silurian-1024x843.png)
![](https://cornwallseatostars.org.uk/wp-content/uploads/2023/01/solow_motion.png)
Where have you reached on the trail?
![](https://cornwallseatostars.org.uk/wp-content/uploads/2023/01/7-Silurian_Trail.png)