Science and archaeology may have come a long way, but many things about the Earth have remained a mystery in the 21st century. One of these mysteries is a strange-looking fossil known simply as the Tully monster. McCoy, whose favourite fossil while growing up had been the Tully Monster, had been fascinated by the mysterious creature, which is believed to have roamed the sea over 300 million years ago. As a result, she took on the project to solve the mystert of this tiny, unassignable creature (it measured about 10cm, according to a report by Ars Technica).
As an unsolved mystery, the Tully Monster nickname eventually became the fossil’s Latin name: Tullimonstrum gregarium.McCoy revealed that two critical discoveries led to their new conclusion. Firstly, most of the Tully Monster fossils had notochords, or flexible vertebrae – similar to humans.