Ordovician Period
485-443 million years ago · Event
The seas diversify enormously — reefs, cephalopods with three-metre shells, the first coral gardens — while the land remains bare rock and the first tentative mosses. It ends in an ice age and the first of the five great mass extinctions.
On these timelines: The Age of Dinosaurs, Master
More from The Age of Dinosaurs
- Cretaceous–Paleogene extinction (66000000 BCE)
- Tyrannosaurus rex (68000000 BCE)
- Mesozoic Era (252000000 BCE)
- Paleozoic Era (541000000 BCE)
- Jurassic Period (201000000 BCE)
- Cretaceous Period (145000000 BCE)
- Triassic Period (252000000 BCE)
- Archaeopteryx and the first birds (150000000 BCE)
Around 485000000 BCE
- First fish, the earliest vertebrates (518000000 BCE)
- Ordovician–Silurian extinction (443000000 BCE)
- Silurian Period (443000000 BCE)