To explain the origins of bipedality and smaller canines, Owen presents the "male provisioning" theory to account for the early appearance of both adaptations.
Berhane Asfaw describes how the present-day hills in the Middle Awash don't look anything like what was there two million years ago, before tectonic earth movements tilted the layers and uplift led to erosion.
Back in the lab in Addis Ababa, Tim White demonstrates how "Ardi's" fragile bones must be painstakingly extracted from the hardened sediments that encase them.
Physiological and anatomical data are combined with modern motion capture technology to create a digital model of a fully-formed Ardipithecus ramidus that moves through an ancient woodland meticulously recreated from intensive fieldwork and analysis.
A revolution in science has transformed the dinosaur story, forcing us to see these remarkable animals as for more complex and successful than was previously believed.
A wary TWISTEX crew tracking the Super Outbreak near Macon, Mississippi is just sensing tornado danger when one traveling at 60 mph crosses the road just up ahead.