revealed a significant rise in marine oxygenation during the Late Paleozoic era (400 million ... evidence indicating the oxygenation of the ocean at the same time, support the hypothesis that ...

The Devonian, part of the Paleozoic era, is otherwise known as the Age of Fishes, as it spawned a remarkable variety of fish. The most formidable of them were the armored placoderms, a group that ...

3 min read During the Ordovician period, part of the Paleozoic era ... which was separated from Gondwana by the narrow Iapitus Ocean. Proto-North America straddled the Equator, though to begin ...