One of the creepiest, crawliest creatures of the Earth may have been swimming before adapting to live on land, new research suggests. Spiders and their arachnid relatives may have actually originated ...

Over 500 million years ago, a small marine creature swam through Cambrian waters. Its name: Mollisonia symmetrica. Long thought to be a distant relative of modern horseshoe crabs, new research now ...

A new analysis of an exquisitely preserved fossil that lived half a billion years ago suggests that arachnids—spiders and their close kin—evolved in the ocean, challenging the widely held belief that ...

Illustration of what the Mollisonia animal would have looked like at the time it lived, more than 500 million years ago. A new analysis of an exquisitely preserved fossil that lived half a billion ...