3 min read During the Ordovician period ... This resulted in the second largest mass extinction of all time, wiping out at least half of all marine animal species about 443 million years ago.

This prehistoric creature was a stem-group arthropod from the early Ordovician Era, 480 million years ago. It was the largest animal to exist in this era and the earliest giant filter feeder.

As one of the coldest periods in Earth's history, the Hirnantian Icehouse played a crucial role in the second-largest mass extinction in Earth's history, known as the Late Ordovician Mass Extinction, ...

Our readers explain the maximum size of a quadrupedal animal and consider the sizes of dinosaurs, blue whales and colonial ...

Horseshoe crabs are one of the oldest species on earth, having been around in more or less the same form since the Ordovician period ... one amazing example of this animal in the Prague Zoo. Karlo, ...

We’re in the Ordovician period ... Some may have even started forming on the shore too. Most of these animals were invertebrates still, like the Cambrian Period. The biggest predators were the ...

The Paleozoic era's Silurian period saw animals and plants finally emerge on land. But first there was a period of biological regrouping following the disastrous climax to the Ordovician.

A capybara is on the loose after escaping from a UK zoo - with the public urged not to approach the creature which is the ...

Cats can come in all shapes and sizes. But what is the biggest cat in the world? Here is what you need to know about the ...

In Ohio, the largest of these aquifers is in ... The hard structure of the animal is composed of plates of crystalline calcium carbonate. Crinoids first appeared in Early Ordovician rocks. Although ...

The world and its ecosystems have been around for a long time — so long that the first mass extinction occurred “just shy” of ...