Some effigy piles from Acton, MA and vicinity

This is right next to the path in Acton Conservation Land. Think it is ancient? I do not.And what might this represent? This is from another place in Acton.
Another like it, from yet another place in Acton.
How about this masterpiece?
It is pretty obvious that these piles are deliberately representational. This one is from Carlisle, on the Acton border.

I call these "effigy piles" because they have visual symmetries and seem to be representational. My impression is that the Acton/Carlisle area has a number of sites with effigy piles. But I almost never see them ouside of the towns that surround Acton. Sometimes you have to clean off the pile a bit before you can see its design and, near home as Acton is, I tend to take longer looking at the piles there. By contrast, when I am "out West" in the wilds of Leominster and Stirling, I rarely settle down, clean off piles, and look at them carefully. So maybe my impressions are based on incomplete observation. Nonetheless, the region centered around Acton, has more effigies than any other region I have visited.