This gap is partly a consequence of the region’s remoteness, but it also reflects something about how the scientific community thought about the possibility of very early human presence in the far Arctic.

Soviet-era archaeology in Siberia was substantial and productive.

Russian researchers investigated sites along the major rivers — the Lena, the Aldan, the tributaries of the lower Ob — and established a picture of Siberian prehistory that extended well back into the Pleistocene.

But the focus was on regions that seemed more plausible as human habitats: the river valleys of south-central Siberia, the forest-steppe zones that seemed more hospitable than the high Arctic.

The extreme northeast — the region above the Arctic Circle, the lands draining to the Arctic Ocean — was underinvestigated for reasons that were partly logistical and partly conceptual.