Invited to deliver a keynote address at the next conference of the Association for Cognitive Semiotics early in 2016, I embarked on a crash course in the evolution of human communication to prepare for my talk in mid-June. I had recently completed Evolution, Cognition, and Performance (2015), so had some notion of the vast territory I was entering. But my survey of the evolutionary dynamics of performance for that book had, I knew, left many questions unanswered, even unasked. What I soon discovered was a rich interdisciplinary conversation among anthropologists, biologists, linguists, psychologists, philosophers, sociologists and many others that, despite its many winding paths, was beginning to converge into a general consensus about the likely origins and evolution of human communication and language during the Pleistocene epoch, roughly 2.5 million years ago to about 11,000 bce. Mostly missing from this general narrative, however, was what I found to be the importance of performance – specifically improvisation – as a necessary initiator of gestural and vocal communication among our Homo erectus ancestors around the middle years of the Pleistocene. While there was general interdisciplinary agreement about the significance of ritual for the evolution of communication among later hunter-gatherer bands, these scholars had overlooked the evidence for the kind of interpersonal trust that, still today, provides the necessary seedbed for improvisation among actors and musicians. The talk I presented in June at the conference about improv as a step toward language, plus the encouraging feedback I received there from my colleagues, is the basis for this short chapter.