On a slow youtube day I see videos about these curiosities. Got to admit there’s no explaining how people with copper and stone tools could carve things so perfectly, even out of granite, and move blocks weighing tens or hundreds of tons, and position them just so.
Never mind why!
Some of the archaeologists’ explanations of later chiseled carvings in Latin America were that the ancients used chicken bones. That was the biggest knock against the “experts” I have ever heard.