Marked changes in human dispersal and development during the
Middle to Upper Paleolithic transition have been attributed to
massive volcanic eruption and/or severe climatic deterioration. We
test this concept using records of volcanic ash layers of the Campanian
Ignimbrite eruption dated to ca. 40,000 y ago (40 ka B.P.).
The distribution of the Campanian Ignimbrite has been enhanced
by the discovery of cryptotephra deposits (volcanic ash layers that
are not visible to the naked eye) in archaeological cave sequences.
They enable us to synchronize archaeological and paleoclimatic
records through the period of transition from Neanderthal to the
earliest anatomically modern human populations in Europe. Our
results confirm that the combined effects of a major volcanic eruption
and severe climatic cooling failed to have lasting impacts on
Neanderthals or early modern humans in Europe. We infer that
modern humans proved a greater competitive threat to indigenous
populations than natural disasters.