Scientists in Wyoming uncovered two exquisitely preserved Edmontosaurus “mummies” that capture the dinosaurs’ full external profiles, including the first-known hooves in any dinosaur, reptile, or land vertebrate. The young adult and juvenile, sealed by a film of clay after death, retain extensive skin surfaces, a neck-to-tail crest that becomes a line of spikes, and pebble-like scales. Led by University of Chicago paleontologist Paul Sereno and published in Science, the team suggests drought and a flash flood created the preservation. Fieldwork in the “mummy zone” also yielded Tyrannosaurus and Triceratops fossils.

Prepared by Olivia Bennett and reviewed by editorial team.