The Ordovician 505 to 440 Million Years Ago The Ordovician period began approximately 510 million years ago, with the end of the Cambrian, and ended around 445 million years ago, with the beginning of the Silurian. At this time, the area north of the tropics was almost entirely ocean, and most of the world's land was collected into the southern super-continent Gondwana. Throughout the ...

458 million years ago - Ordovician Period.

Ordovician period (510- 438 million years ago) - Ordovician extinction (440-450 million years ago).

During the Ordovician ancient oceans separated the barren continents of Laurentia, Baltica, Siberia and Gondwana.

A Gallery of Fossils from the Upper Ordovician Strata of the Cincinnati Series.

Ordovician Period Time of Fish (505-438 mya).

The Fossil Company - The Palaeozoic Era. An illustrated geological time line for the Palaeozoic era, which includes the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian periods.

Ordovician period [from the Ordovices, ancient tribe of N Wales], second period of the Paleozoic era of geologic time from 505 to 438 million years ago.