Newly excavated skeletal remains of an ankylosaurid — a large armored herbivore that lived during the Cretaceous Period — may indicate that members of this family of dinosaurs were able to dig, according to a study published in Scientific Reports. The specimen, known as MPC-D 100/1359, may further our understanding of ankylosaurid behavior during the Late Cretaceous (84-72 million years ago).
Yuong-Nam Lee and colleagues excavated the skeletal elements of MPC-D 100/1359 from a deposit of the Baruungoyot Formation in the southern Gobi Desert, Mongolia, where it was discovered in the 1970s. The authors suggest that several anatomical features of MPC-D 100/1359 could indicate that the ankylosaurid was adapted for digging. The bones in its forefeet are arranged in a shallow arc, which could have enabled it to dig soft earth. The fusion of several vertebrae and the decreased number of bones in its hindfeet, compared to other dinosaurs, may have helped anchor MPC-D 100/1359 when digging or moving its tail. The body shape of MPC-D 100/1359, which is wider in the middle and narrower at the front and rear, may have helped its body to remain straight when digging.
The authors speculate that MPC-D 100/1359, may have dug the ground in order to reach water, minerals, or roots for food and may even have crouched in shallows pits to protect its soft underside from predators. As similar anatomical features have been reported in other ankylosaurids, the findings suggest that the ability to dig may have been common to other members of this family of dinosaurs as well.
Reference: “A new ankylosaurid skeleton from the Upper Cretaceous Baruungoyot Formation of Mongolia: its implications for ankylosaurid postcranial evolution” by Jin-Young Park, Yuong-Nam Lee, Philip J. Currie, Michael J. Ryan, Phil Bell, Robin Sissons, Eva B. Koppelhus, Rinchen Barsbold, Sungjin Lee and Su-Hwan Kim, 18 March 2021, Scientific Reports.