Equinox was an important time of year for Southwestern hunter-gatherers, just as it is for modern agricultural people. Equinox designates times of year when earth fertility begins and ends. Harvests, migrations, and seed planting happened (still happens) at the equinoxes, so it is natural that ceremonial sites were built to commemorate the seasons of Equinox.
Beyond the practical aspects of marking a time of year when something needs to happen, like an appointment, are philosophical concepts tied to times of year when fertility the focus. I think it is very interesting that immediately next to the cave with the Equinox Calendar are two large boulders featuring pictographs and petroglyphs with crosshatched patterns. The pictographs of the crosshatches are painted within natural bowls on the surface of the boulder. This same kind of symbolism, crosshatches painted on a round vessel, is used worldwide to indicate a concept similar to “eternal life”. In ancient agricultural societies crop fields were planned in the crosshatch pattern (with specific east/west designations) to imitate this metaphysical concept and inspire powerful universal synergy with the production of life-giving food.
There is a school of thought that all geometric patterns in a Rock Art are merely transcriptions of entopic patterns that the inner eye sees while in the trance state. While the eye may see entopic patterns while the shaman is in a trance state, that does not preclude the shaman from adding meaning to that pattern once he sobers up and chooses an image to carve or paint. I don’t think these two philosophies about rock art (entopic vs. representstional) are in conflict. If the human eye, regardless of geography and state of cultural evolution, will see the same entopic patterns in trance, then that means all humans who have ever been in trance have been exposed to the same patterns, but since we also know that the identifying characteristic of the human mind is that it ascribes meaning to everything, the interesting work is in trying to understand what the symbols meant to prehistoric people.
There’s a related question that I just thought of. If you go into trance with a specific and intense intention, can you manifest particular entopic patterns to match your intended experience, to connect with certain symbols that have meaning to you?
To me, it seems very feasible that pictographs and petroglyph that overlook an ancient ceremonial site, that commemorates times of year when the proliferation of life is the focus, should depict concepts like “eternal life”. The really interesting question is, do ideas like these with identical symbolism worldwide automatically occur in the minds of humans or did they travel? The quest for that answer continues. In the meantime, see how these symbols present in the Mojave Desert.