I've got a pet theory about some western mythological tropes where horses are the economic and technological development that ties them together. the essential idea is that the young heroes mentored by centaurs (achillies and chiron, etc.) and "wisdom originating in the east," come from horse tribes from the steppes influencing proto-greek civilization, where centaurs came to represent those plainspeople in their mythology. as in central and east asia, by the result of being given empires, horsemanship was a channel for both evolutionary and divine assent, where if these other beings in nature favoured the people with the qualitites to ride them, then they were chosen to lead. horses became a force of evolutionary selection for us.
it's basically an "ancient aliens" quality theory about horses, which I'm sure archeologists will love as much as they do the tv one, but horses are more than just a thread in our history, they are a force of it. relating to other beings in a complete cultural symbiosis like that seems like a key evolutionary achievement to unlock on the way to becoming starfaring, and if you have any background working with them, they are rare companion beings to us in the real of nature we inhabit. lunacy? perhaps, but experiencing the world with horses isn't just pony rides, it's an encompassing philosophical pursuit.