Artist Sophie Smith "listens" to fossils to seek inspiration, but her latest subjects, a pair of ape-like human ancestors, millions of years old, could give her something else as well. Never has she needed a clear perspective on human descent so much, for now she is unexpectedly pregnant.

As Sophie struggles to make art and make a decision, her speculations frame and introduce the real stories of seventy-five years in a proto-human community, the "foot-ape" Tribe of the River Confluence. There is the community founder who must make a terrible choice to reclaim her power and dignity....