Fossils found in Ethiopia have revealed that early humans coexisted with australopithecus, with some findings suggesting they lived alongside a mystery species or a previously unknown human cousin. The discovery, which includes ancient teeth and a strange foot fossil, indicates that multiple types of human ancestors lived together over 2 million years ago. The exact nature of these early human interactions and relationships is still being uncovered, with some findings also shedding light on the life and death of a well-known early human ancestor.