prehistory, n.All

Prehistory (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠mankind's forgotten childhood: since evolution, we know the species had one, and that it is unknown — that is, forgotten.