They lacked the neshama. Recall that the Talmud was redacted a millennium before paleontology raised the scientific question of pre-human hominids. The Talmud learned of hominids from nuances in the text of Genesis. Science has confirmed the ancient predictions of Genesis. Museums make the break between pre-history and history at about 6000 years ago, marked by the invention of writing and the appearance of large cities.
Necessity is the mother of invention.
The sudden expansion of clan-sized towns and settlements such as ancient Jericho, into cities necessitated commerce and administration, which in turn required record keeping and hence, writing. That is a question unanswerable by science. Not just good, but very good. Still young children get MS and earthquakes shake down buildings to crush the innocent. The same God that streaks the sky with a rainbow of red at sunrise and produces the beauty of a flower must also take credit for these horrors.