Eusthenopteron, an ancient fish, was an agile predator with a nasty bite. Eusthenopteron had many unique features shared by the earliest land vertebrates.
Ichthyostega: not quite fish and not quite amphibian. What exactly was this ancient creature? We do know that it had lungs, limbs and lived mostly on land.
The straigh-shelled nautiloid was the great white shark of its time. A perfectly designed killing machine, it was up to 20 feet long and had an insatiable hunger.
The coiled nautiloid was among the top predators of the Ordovician. Its coiled shell allowed it to survive at much deeper depths than the straight-shelled nautiloids.
New research reveals that terror birds - large, prehistoric carnivores that evolved alongside dinosaurs - hunted their prey with quick, opportunistic strikes. Trace Dominguez reports.
A Tyrannosaurus rex goes head-to-head with a prehistoric dragon. The dragon is outmatched by the T. rex's size, but it's got a few tricks up its sleeve.
What strange things lurk deep in the heart of caves? Some believe that within the darkness live mysterious, flying bat-like creatures known as cave demons.