^Wow, that creature on the left there looks really like an elongated E.T.
Do you know of any plausible interpretation of that thing? I guess it could just be a fantasy creature?
In a sense, anthropology sometimes sounds like trying to figure out what people were thinking based on some pottery here, some imagery here. I mean, you have a very few pieces of a puzzle and the rest you have to fill in on your own as best you can. It sounds pretty hard!
Depending on how you fill in the pieces, I'm sure you could use such art to draw all sorts of conclusions, for example about alien visitors. I'm sure noise agrees, at least to some extent, that such interpretations is not the right thing to do. Coming from biology, I would say it's the wrong thing to do based on principles of parsimony. If you make the assumption that the image is an illustration of an alien who visited these peoples, then you have to assume that aliens exist
and visited earth and these people at some point(s) in time. If you assume that it's an illustration of a figment of imagination, you don't have to make any "new" assumptions about our universe. We already know people are capable of art and fantasy.
edit :
Parsimony is sorta about making as few wrong assumptions as possible. For example we know people are smart and can build things. If we assume people made the pyramids, we have a hypothesis which is broadly congruent with this knowledge. If we assume aliens guided the builders or even built the pyramids, then we have to make a whole new set of assumptions to accomodate that hypothesis.