Des Moines University associate professor and vertebrate paleontologist Julie Meachen helps set up a grid that will allow scientists to document where fossils are found in northern Wyoming's Natural Trap Cave near Lovell, Wyo. on July 8, 2021. Thousands of animals have fallen into the cave and perished over the past 30,000 years, making the site a treasure trove for paleontologists. (Mike Clark/The Billings Gazette via AP)