The people at Bluefish Caves were at the beginning of that accumulation on one specific branch of the human family tree, in one specific part of the world.

Their descendants would go on to populate two continents, to develop the full diversity of Native American cultures, languages, technologies, and traditions — from the Arctic to Tierra del Fuego, from the Atlantic to the Pacific.

The cut marks on the horse’s jaw are the beginning of that story, or at least the oldest surviving evidence of its beginning that archaeologists have yet found.

They are not a curiosity from a distant, irrelevant past.