Since then, it's been my job to bring ancient people back to life, a field called paleo-reconstruction. We convey science's best guess about how these human relatives looked. I start with a plaster cast of the skull and lay clay "muscles" over it, building thin layers to mimic flesh. The tricky parts are the features. Right now I'm working on a Homo naledi—a 300,000-year-old relative of ours that archaeologists discovered in 2013. Many hominids looked more like chimpanzees than today's humans, so I could make the nose chimplike or modern. But I'm waiting for the scientists to determine that, based on how much H. naledi's teeth or other remains resemble those of better-understood species.