New Insights into Dinosaur Mummification

Recently, new research has unveiled intriguing details about the mummification process of dinosaur fossils discovered in the Lance Formation in eastern Wyoming. These findings have raised questions about the nature of the petrified skin, which was once believed to be remnants of real dinosaur flesh and skin.

The Beginning with Charles Sternberg

Over a century ago, the renowned fossil collector Charles Sternberg discovered the first dinosaur mummy of the Edmontosaurus species in the sandstone of the Lance Formation. This discovery was unique as the dinosaur remains were covered with petrified flesh and skin, making it the first dinosaur mummy ever discovered.

Just two years later, Sternberg discovered another mummy in the same area. These discoveries were thought to provide a rare glimpse into the appearance and skin structure of dinosaurs.

Findings of Recent Research

In a recent study published by researcher Paul Sereno from the University of Chicago, it was revealed that the petrified skin found on the dinosaur mummies in the Lance Formation is not actually remnants of flesh and skin, but rather clay molds formed by microbes during the decomposition process.

Sereno explains that this process, known for preserving the shape of soft-bodied animals in low-oxygen environments like lake and ocean beds, was unexpected in an oxygen-rich environment like sand submerged by floodwaters.

The Clay Mummification Process

When animals are preserved in this manner, all the soft external tissues turn into thin clay layers no more than 1 millimeter thick. Sereno suggests that the bodies dried due to drought before being suddenly covered by sediments from floods.

Subsequently, a layer of bacteria adhered to the moist, porous surface to form a biofilm, attracting surrounding clay. After weeks of burial, the soft parts decomposed and were washed away by groundwater, leaving the clay mold to preserve the external shape of what lay beneath the skin.

New Discoveries in the Mummy Area

Sereno and his team were able to discover several other mummies near Sternberg’s original site. These discoveries include Triceratops horridus and Tyrannosaurus rex, along with two Edmontosaurus annectens described for the first time in the new study.

One of these dinosaurs was two years old at the time of death, and the other ranged from five to eight years old, making them a “late juvenile” and an “early adult,” respectively. They were named “Ed Junior” and “Ed Senior.”

Conclusion

This study sheds light on a new mummification process that may change our understanding of how dinosaurs were preserved in the past. However, the most exciting question remains how applicable this process is to other mummies discovered at different sites around the world.