Marine fossil specimens unearthed in northern Portugal are filling a gap in understanding evolution during the Middle Ordovician period. A clutch of marine fossil specimens unearthed in northern ...

During the Ordovician period, the concentration of CO2 in the earth's atmosphere was about eight times higher than today. It has been hard to explain why the climate cooled and why the Ordovician ...

This surprising hypothesis, published in Earth and Planetary Science Letters, stems from plate tectonic reconstructions for ...

During the Ordovician period, the concentration of carbon dioxide in Earth's atmosphere was about eight times higher than today. It has been hard to explain why the climate cooled and why the ...

Subdivision and correlation of the Ordovician System serve as the time scale for constraining the major geological and biological events during the Ordovician Period. Currently a globally unified ...

Scientists studying the geology of the Ordovician Period about 466 million years ago report evidence that Earth's ring system created a telltale pattern of impact craters, and it may also explain ...

Fossils from the Cincinnati area are renowned for their abundance, variety and ease of collecting. The animals that produced those fossils lived at the end of the Ordovician Period 450 million ...

The extra legs caterpillars have appear have origins in the primitive crustaceans that insects evolved from during the Ordovician period over 400 million years ago.

The Silurian Period occurred from 443.8 million to 419.2 million years ago. It was the third period in the Paleozoic Era. It followed the Ordovician Period and preceded the Devonian Period. During ...