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Ordovician–Silurian Extinction: Ice Strikes the Seas

By Michael Alan Prestwood

Mon 13 Apr 2026
Published 3 days ago.
Updated 3 days ago.
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The Ordovician–Silurian extinction shows how climate change can reshape evolution by collapsing old ecosystems and opening space for new life.

Ordovician–Silurian Extinction: Ice Strikes the Seas

~444 Million Years Ago
Cause: Global Cooling and Falling Seas

This extinction hit marine life hard, especially organisms living in shallow seas. The leading explanation centers on glaciation over Gondwana, falling sea levels, and disrupted ocean habitats. As seas withdrew, vast marine ecosystems collapsed, clearing space for new evolutionary paths in the Silurian.

— map / TST —

Michael Alan Prestwood
Author & Natural Philosopher
Prestwood writes on science-first philosophy, with particular attention to the convergence of disciplines. Drawing on his TST Framework, his work emphasizes rational inquiry grounded in empirical observation while engaging questions at the edges of established knowledge. With TouchstoneTruth positioned as a living touchstone, this work aims to contribute reliable, evolving analysis in an emerging AI era where the credibility of information is increasingly contested.
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