When we think of major innovations in human history, what comes to mind are inert technologies - from the wheel to the computer - but one of the most significant developments occurred as the result of the relationship between humans and another animal, horses. The domestication of horses brought about a major sea-change in human society, as we became much more mobile.  It affected everything from agriculture to warfare to the dissemination of language and culture. To discuss the domestication of horses and the impact of this relationship, I spoke with  William Taylor,  Assistant Professor and Curator of Archeology at the University of Colorado, Boulder.  As Taylor explains, our understanding of this history continues to evolve thanks to new scientific tools, such as new types of genomic sequencing, but also due the work of anthropologists who observe present-day horse culture in Mongolia, contemporary Ukraine and other parts of the Eurasian steppes where the domestication of horses first took place.