Prehistoric prey and predator fossil discovery reveals a violent fight for survival millions of years ago, in first-ever evolutionary arms race

When a pesky pest is trying to bore its way into your home, the natural reaction is to build a stronger defense to keep it out. 

According to a new study based on fossils from the Cambrian, this is what evolved to happen between two species of sea creature in the ocean covering what is now South Australia over 500 million years ago, making it the oldest known example of a…