Dante and Lexy, young siblings, volunteered at the local Science Center assisting the science staff store the prehistoric fossils dug up from nearby sites. One day, the center received a crate from Ethiopia with a mysterious package that would lead them on a journey back in time, not by a few years, or even a few decades, but by millions of years ago. They would face predators no human had ever encountered, including the deadliest one of all, their own ancestors, the hominids.
This was an Audible short book and geared for YA but I loved it. I learned about fossils, ancient humans etc. I would recommend it for kids and YA as well as grown ups.