Ancient arthropod monster was a ‘peaceful giant’, scientists say

Gentle giant: The Ordovician Period arthropod, Aegirocassis benmoulae, shown feeding on a plankton cloud in this artist's rendering.

This monster from the primordial seas was not only big and kind of weird, but also an evolutionary trendsetter.

Scientists have announced the discovery in southeastern Morocco of beautifully preserved fossils of a huge arthropod – the group that includes crabs, scorpions, insects, spiders, centipedes and more – that lived 480 million years ago.