August 6, 2009—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.
But new 3-D models, made by a CT-scanning device, open an even wider window into the critters' daily lives, according to a study that appeared this week in the journal Biology Letters.
(Related: "Ancient Spider 'Digitally Dissected.'")
For instance, the model revealed that E. prestivicii's back was studded with defensive spikes (above, right), which may have made carnivorous amphibians think twice about gobbling up the insect.
And C. hindi's two front legs were angled forward, presumably so it could grasp prey before killing it.
The leg angle suggests the spider ancestor hid in logs and under leaf fronds, waiting to ambush smaller insects—much like the modern-day crab spider, the study says.
"Our models almost bring these ancient creatures back to life, and it's really exciting to be able to look at them in such detail," study leader Russell Garwood, a Ph.D. student at Imperial College London, said in a statement.
Garwood and colleagues added that the new technique could be used to digitally resurrect many other ancient creatures that stalked early Earth.