An artist's illustration shows Deinosuchus riograndensis swimming with an early alligator relative in the wetlands of the Western Interior Seaway in southwestern North America, during the Late ...

BOULDER, Colo. — Paleontologists recently discovered a rare mammal fossil in western Colorado. It's a genus of mammal that lived between 70 million and 75 million years ago and has never been seen ...

Rare fossils uncovered in Colorado show an unexpected swamp-dwelling creature lived among the dinosaurs millions of years ago. A team of paleontologists uncovered the “new (or, more accurately, very ...