“Vivid descriptions of the animals, the cave, and the scientists are complemented by the original art and photos that work together unusually well.” —Booklist   What was life like millions of years ago? The answer lies deep underground, in a place once home to a ferocious predator much larger than most animals walking around today. Through photographs and detailed illustrations, readers will learn how the secrets buried in a midwestern hillside helped scientists understand early life on Earth. This book’s simple but informative format allows readers to follow along as paleontologist Matt Forir and his team of experts unravel a prehistoric mystery.   “[An] account of the discovery and early exploration of Missouri’s Riverbluff Cave, the oldest found so far in this country with fossil remains . . . may excite curiosity about the Riverbluff finds.” —Kirkus Reviews