Duck-billed dinosaur fleshy midline and hooves reveal terrestrial clay-template “mummification”
- Paul C. Sereno
- Evan T. Saitta
- Daniel Vidal
- Nathan Myhrvold
- María Ciudad Real
- Stephanie L. Baumgart
- Lauren L. Bop
- Tyler M. Keillor
- Marcus Eriksen
- Kraig Derstler
2025-10-23
Two “mummies” of the end-Cretaceous duck-billed dinosaur Edmontosaurus annectens preserve a fleshy crest over the neck and trunk, an interdigitating spike row over the hips and tail, and hooves capping the toes of the hind feet. A battery of tests showed that all of the fossilized integument (skin, spike, and hoof) are preserved as a thin (less than 1 millimeter) clay template that formed on the surface of a buried carcass during decay before the loss of all soft tissues and organic compounds. Unlike the underlying permineralized skeletal bone, the integument renderings of these “dinosaur mummies” are preserved as a thin external clay mask, a templating process documented previously only in anoxic marine settings.