Natural History: Large Cover-Up

Borealopelta markmitchelli was a heavily armored, spiny, plant-eating ankylosaur that stretched 5.5 meters long, weighed over 1,300 kilograms, and lived in the early Cretaceous Period, about 110 million years ago. Its fossil was found in 2011 at an oil-sands mine in northeastern Alberta, Canada. The species was named for the technician who spent over five years cleaning and preparing it for study. The conditions under which B. markmitchelli fossilized were incredibly rare, resulting in remarkable three-dimensional preservation of soft tissues, including the skin. A study of the skin has led to an unexpected discovery about the dinosaur’s coloration.

A remarkably well-preserved Borealopelta markmitchelli fossil shows the dinosaur’s armored body in great detail.
Royal Tyrrell Museum of Palaeontology, Drumheller, Canada