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How did Pangea’s formation affect shallow-water marine habitats?

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Watch Earth's Continents Move — paleogeography Watch a time-lapse of Earth changing through geologic time, from the Cambrian Era to the projected period of Pangea Proxima.

The formation of the supercontinent Pangea significantly altered global paleogeography, leading to a marked decline in the extent of shallow-water habitats.1

As the continents amalgamated, the reduction in total shoreline length and the configuration of landmasses inhibited the circulation of cold polar waters into tropical regions. This restricted circulation, combined with lower global sea levels during the Pangean supercycle, reduced dissolved oxygen levels in the remaining warm-water environments.12

These environmental stressors had profound consequences for marine life, contributing to a massive reduction in biodiversity and playing a role in the mass extinction event at the end of the Permian Period. In contrast, the subsequent breakup of Pangea increased shoreline length and created new marine channels, which facilitated the mixing of ocean waters and the expansion of shallow-water habitats.1