Fossil bones from T. rex and others reveal battle scars.
Trackways provide important clues.
Some of the best evidence comes from T. rex.
Scientists find colored, feathered dinosaur fossils.
Scientists examine the bones of dinosaurs for clues.
An asteroid impact might have played a role.
The challenges scientists face in cloning DNA.
Fossils are naturally-preserved physical traces of long-dead organisms.
Dinosaur fossils are found almost exclusively in sedimentary rocks.
How fossils are prospected and removed from rocks.