This is how it begins. A bonobo chimp has been observed making primitive flint tools. His name isn't Caesar, it's Kanzi, and he's produced tools that show similar wear patterns to the ones created by the earliest humans. First Kanzi was trained in flint knapping, a technique used to create flat surfaces on otherwise round stones. Once trained, he made 156 different tools, and used them to break open logs that contained food. Other chimps accomplished the same task by smashing the logs on the ground.
This isn't the first time primates have been observed using tools--other chimps have been known to use sticks to fish for termites--but it is the first time we've observed an animal making tools analogous to the ones made by early hominids 2-3 million years ago. (h/t to Sott)