Smithsonian researchers have linked discoveries within Arizona’s Petrified Forest National Park with a previously unknown ...

"North america’s oldest pterosaur unearthed in Arizona’s Triassic time capsule." ScienceDaily. ScienceDaily, 9 July 2025. <www.sciencedaily.com / releases / 2025 / 07 / 250708045700.htm>.

A rare Triassic fossil site reveals North America's oldest known pterosaur, Eotephradactylus mcintireae, in what was once a rich ecosystem.

An outcrop at Owl Rock contains volcanic ash that has allowed geologists to date its age within 100,000 years. The Owl Rock Member, as the deposit is known, is 130 meters (420 feet) thick.

Scientists have unearthed in Arizona fossils from an assemblage of animals, including North America’s oldest-known flying reptile, that reveal a time of transition when venerable lineages that were ...