Thank you, cheap seats. That will be quite enough.
Now that the guffaws have died down, a serious adult source has offered a thoughtful suggestion:
An international team of researchers led by archaeologist Ella Assaf of Tel-Aviv University in Israel made a close examination of ten such stones found at Qesem Cave, a Lower Paleolithic site occupied by early humans between 400,000 and 200,000 years ago.
This is curious, because it’s the latest known appearance of these tools, a timeframe when other communities had long ago stopped using them. So Assaf and her team investigated to find out more about these stones, and how they got there.Michelle Starr, “We May Finally Know Why Early Humans Kept These Mysterious Stone Balls Around ” at ScienceAlert
It turns out that these early people were probably using the stones to smash open bones, to get at the nutritious marrow.
“As bone marrow played a central role in human nutrition in the Lower Paleolithic, and our experimental results show that the morphology and characteristics of shaped stone ball replicas are well-suited for the extraction of bone marrow, we suggest that these features might have been the reason for their collection and use at Qesem Cave.”Michelle Starr, “We May Finally Know Why Early Humans Kept These Mysterious Stone Balls Around ” at ScienceAlert
Paper. (open access)