125,000–70,000 BCE: Submerged Coastal CivilizationsThe Yonaguni Monument, now under sea level, possibly built before the last glacial period.Where this sits. The monument is disputed. Geologists read the formation as natural sandstone fracturing along bedding planes — the sharp angles occur without builders. Not disputed: sea levels were far lower, these coastlines were dry land, and whatever stood on them is now underwater.
Dwarka (India), also now submerged.
The Denisovans, a mysterious human species, lived in Siberia and Tibet, and Southeast Asia.An enigmatic branch of archaic humans that coexisted with Neanderthals and Homo sapiensSome theories suggest Denisovans may have had advanced tool-making abilities and possibly taught early Homo sapiens new techniques.The Denisova Cave contained artifacts beyond what was expected for archaic humans, including jewelry and tools.Denisovans interbred with early Homo sapiens, contributing significant DNA to modern human populations.