Knowing absolutely nothing whatsoever about paleoanthropology, how much d'ya wanna bet this was precisely the point at which early man harnassed fire?
Other candidates might be: Discovered seed-based plant agriculture, discovered husbandry-based animal agriculture, discovered spoken language, discovered the idea of rudimentary written notations, discovered the spear [probably just a tad early for bows and arrows],...
Or maybe was privy to a little divine intervention?
I see gender bias in this article. It mentions the influence of older WOMEN on society...but fails to mention the men! (Guess the brutes were too busy hunting bison to pass on knowledge at the hearth???)
These (IMO) are the most likely, they already had all the others.
Or found the obelisk?
Nahhh. It was the beads.