Denny’s mother was part of that flow.

She, or her recent ancestors, had come from the west.

And at some point on that journey, or at its end, they encountered the Denisovans.

The Denisovan father’s background is less well-characterized, but analysis of the paternal chromosomes found in Denny’s genome suggests he belonged to the same Denisovan population represented by other Denisova Cave individuals — the local Denisovans of the Altai region.

This creates a picture of an encounter between a western Neanderthal who had traveled east and a local Denisovan — a meeting at the frontier between two worlds.