I spent a day at Nine-Mile canyon this summer. It's actually more like 40 miles, but has been called the "longest art gallery in the world," since it's chock full of pictoglyphs from the Fremont and Anasazi cultures. One of them is a spectacular display. It's right near the road, and there's a parking lot nearby. That's it on the right. This panel is about twelve feet long and about six feet high, so it's good sized.
There are a number of figures on the right side, four of them I think, that have bows, and are apparently hunters. If you look closely, you can see what appear to be wings on the backs of the figures. Here's an enlargement.
The funny thing is that the largest of the figures, the one on the right, seems to be sporting a goodly sized penis. Now, anthropologists will muse about the significance of that penis, and of the "wings," and of the horned figure top center. But they make, it seems to me, two unwarranted assumptions. First, they assume that the piece has a structure -- that it was either done at one time or added to with intent to expand the meaning.
The second assumption is that the intent was serious, even reverential.
I beg to disagree. People are people, whether they live now or 800 years ago. More important, teenagers are teenagers.
I'd venture to suggest that, oh about the year 1000, a couple of teen aged boys climbed the rock one night and when the left the guy on the right had his penis.
Sacrilege, but it strikes me as right.