The Earth: a ringed planet, much like Saturn, surrounded by a hula hoop of asteroids. The summit of Mount Everest: a tropical ...

Back when the Earth was crawling with trilobites and other strange shelled creatures ... This era of intense bombardment, known as the Ordovician impact spike, may have resulted from meteorites ...

A huge 75-foot-tall square boulder deep in Wyoming’s Bighorn Mountains has been baffling people since it was discovered.

In the past 500 million years on Earth, there have been five mass extinctions. Here are a few incredible species that managed ...

Though unfinished, Salter's monograph has thirty excellent plates which make it an essential starting point for the study of British Devonian, Silurian and Ordovician trilobites. The monograph is also ...

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This was when organisms made the transition from unicellular to multicellular, including hard-shelled animals (e.g. trilobites). Until, of course, mass extinction wiped about 83% of these from Earth.