The rock carving was found in the Kalahari Desert of Botswana. Red spear points were found near the site which may signify there was a complex rule set for the cult. To give some background, humans were scattered around in Africa at this time and were also just beginning to penetrate the Mideast.
This discovery is big. Some evolutionary biologist, including Richard Dawkins with his book God Delusion, have argued the idea of a higher being and religion are by-products from the latter days of evolution. The giant snake runs counter to this argument (yet does not discredit the idea). The find advances the theory that religion is a part of human nature. Some deep thoughts to chew on... (and if cosmology is not your thing, just enjoy thinking about a giant snake idol!)
Hat Tip: Evangelical Catholicism