The Ordovician was a geological period of ancient Earth, spanning from roughly 485 to 443 million years ago. It witnessed a great diversification of marine life, including the rise of early fish, and ended with a major extinction event.
The Ordovician was a geological period of ancient Earth, spanning from roughly 485 to 443 million years ago. It witnessed a great diversification of marine life, including the rise of early fish, and ended with a major extinction event.