The researchers' idea that Earth once had rings comes from reconstructions of Earth's plate tectonics from the Ordovician period—which ran between 485.4 million years and 443.8 million years ago ...

The Ordovician period and its impact spike correspond closely with a period of intense cold for our planet known as the Hirnantian glaciation—or, more dramatically, as the Hirnantian Icehouse.

The Ordovician period is notable for the Great Ordovician Biodiversification Event, a time when life on Earth experienced a remarkable evolutionary expansion.

In a first-of-its-kind study, Stanford researchers have measured how the abundance of ocean life has changed over the past ...

During the Ordovician Period, a time of significant changes for Earth’s life-forms, plate tectonics and climate, the planet experienced a peak in meteorite strikes.

Long before the dawn of humans, dinosaurs, insects or even trees, a cascade of unfortunate events threatened to end life on earth. During the Ordovician Period, around 485 to 444 million years ago, ...

If you were to look up from Earth some 466 million years ago, you might have seen a gleaming ring stretching across the sky, some scientists say.

Could You Survive The Ordovician Period? Season 2 Episode 3 | 58m 26s. The End-Ordovician Extinction was the first of the so-called ‘Big Five’ mass extinctions in the history of life on Earth ...

Armored and jawless Jawless fishes from the Ordovician Period — 488.3 million to 443.7 million years ago — are called ostracoderms, after their armored skin, and most of them are known from ...

Exceptionally well-preserved fossils of tiny worms, starfish, sponges, barnacles and other creatures with no modern parallel discovered at a quarry in Wales are painting a picture of life on Earth ...

The Ordovician period and its impact spike correspond closely with a period of intense cold for our planet known as the Hirnantian glaciation—or, more dramatically, as the Hirnantian Icehouse.

During the Ordovician Period, a time of significant changes for Earth’s life-forms, plate tectonics and climate, the planet experienced a peak in meteorite strikes.