Last week for Fossil Friday, I posted the sacrum of a ceratopsid, a large horned dinosaur related to Triceratops. The sacrum is a series of fused vertebrae to which the hip bones attach. Today, I want to show you one of those hip bones from the same ceratopsid individual. This is the left ilium, showing the inner surface where it would have attached to the sacral ribs along a series of deep facets. At about 80 centimeters long, this ilium is not terribly big for a ceratopsid, but it still would have been a hefty animal, plodding around the forests and swamps of Late Cretaceous New Mexico.In the coming months, we will create 3D-printed replicas of the sacrum and ilium of this ceratopsid to see how they fit together, the first step in rebuilding this 79-million-year-old skeleton. We also have several vertebrae and ribs from the back. This specimen was collected during the 2017 and 2018 field seasons by staff and volunteers from the Western Science Center, Zuni Dinosaur Institute for Geosciences, and Southwest Paleontological Society. The sacrum and ilium have both been prepped by WSC lab volunteer Joe Reavis.Post by Curator Dr. Andrew McDonald.