The discovery of million-year-old bone tools has raised questions about human ancestors and who may have made the first stone tools. The findings, from various locations including africa, china, sulawesi, and uzbekistan, suggest that early humans may have used bone tools earlier than previously thought, with some sites dating back as far as 2.9 million years. The identity of the humans who made these tools remains unclear, with some discoveries prompting consideration of mystery humans or extinct species.