It was every spider for itself in the brutal pre-dinosaur world of the Carboniferous period, new 3-D images reveal.
About 359 to 299 million years ago, Earth teemed with newly evolved insects and hungry amphibians that had just crawled onto land.
Among them were two coin-size, spiderlike creatures-Cryptomartus hindi (pictured above at left) and Eophrynus prestvicii (right)-which scurried along the bottoms of the world's first rain forests.
Fossils of the bugs had already given scientists some insights into their lives: E. prestvicii, for instance, had long legs that probably allowed it to run through leaf litter after its prey.