The pigments.

The evidence of Neanderthal use of marine shells as ornaments, recovered from sites along the Iberian coast.

These were not the products of creatures incapable of symbolic thought.

By the time the Cambridge team began their new excavations at Shanidar in 2015, the field had largely moved past the old model.

The question was no longer whether Neanderthals were cognitively complex — the evidence had established that they were — but rather what the specific dimensions of that complexity were and how they compared to the cognitive profile of contemporary modern humans.

Shanidar Z and the burial cluster evidence entered this reframed debate.