Other forms: Silurians
The Silurian is the third and shortest period of the Paleozoic era, lasting from about 444 to 419 million years ago. It was a time of recovery after a mass extinction event.
The Silurian followed the Ordovician, which ended with freezing conditions that killed off many species. The Silurian's rising sea levels and warmer temperatures supported the development of new species, such as giant sea scorpions as long as six feet! Small, land-dwelling animals and terrestrial plants became more common and complex. Geologist Roderick Murchison named this period after the ancient Celtic tribe the Silures, who lived in Wales, where he first discovered evidence for it.