I can't help but remember a series of dreams I had many years ago, which seemed to involve being on an alien world, inhabited by "angelic" beings of sorts, significantly different to humans in many ways. I once asked what they were descended from, and they revealed to me a pig...
Ever since then, this entire issue of Jewish (and later Muslim) proscription from eating from the pig has really piqued my curiousity - whilst the traditional answer is that pigs behave in unclean ways, I have difficult understanding how the pig is significantly more dirty than any other grazing animal, that spends its life close to mud.
I keep wondering if perhaps pigs may have a more hidden meaning in Kabbalah and Jewish mysticism, and I am reminded of the animal imagery used in conjunction with angelic beings, such as in Ezekiel and Revelations - the re-occuring Cherubim figure who has four faces - lion, eagle, bull - and one face that is somehow like a man, yet isn't.
Of course, the cherubim descriptions state a relationship between angels and animals that is open to all sorts of interpretations, from the theological, anthropological, comparative and historical.
However, I can't help but wonder at the suggestion from this that, perhaps, across the stars, there are only a select group of animal "types" that can ever evolve into sentient form (and perhaps even evolve into such spiritually evolved forms as to be called "angelic"). And that of these animal "types", the nearest equivalents of three of them on our planet include the eagle, bull, and lion.
However, perhaps the fourth type that becomes "man-like" can evolve from different species types, of which the ape took the lead on earth, but that on other worlds - where conditions are perhaps very different - other animals, such as an equivalent to the pig, may have the evolutionary advantage and thus evolve into a sentient form equivalent to human.
What I especially found interesting about the dreams I had is that there were other details I was able to pull from them, that later corroborated - such as that in the dream, the planet was especially bathed in Ultra-Violet light which would be ordinarily dangerous to any type of human skin. Funny that pig skin is very resistant to UV damage.
Perhaps somewhere out there, among the billions of stars, on worlds with particularly dangerous concentrations of Ultra-violet radiation, the pig is one of the few animals that evolution can shape towards sentient form.
As for why the eating of the pig should be forbidden - not entirely sure. As before, I keep wondering if there's a comment in Kabbalah somewhere (perhaps regarded as somewhat odd or heretical) that pigs, rather than being unclean, need to be avoided for their angelic association. That would help tally the overall concept here with other concepts, such as impact of Vedic worship of cows in India, for example. And also Ancient Egypt managed to dedicate an entire city to the cat, of which the passive form was Bastet, but the aggressive form was the lioness Sekhmet. Interesting that Sekhmet is very much related to Hathor, the beautiful female-cow goddess of Ancient Egypt.