Researchers say a small fossil from the middle Jurassic provides some of the oldest evidence of chewing and swallowing as well as suckling — all distinctly mammalian traits. Chang-Fu Zhou/Shandong University of Science and Technology Chang-Fu Zhou/Shandong University of Science and Technology Over the years, a section of the Inner Mongolia region of China has coughed up heaps of remarkable fossils, ranging from feathered dinosaurs to flying reptiles. "To say it's [a] hot spot is actually [an] understatement," says Zhe-Xi Luo, a paleontologist at the University of Chicago. For new discoveries, everyday mysteries, and the science behind the headlines, follow…