I definitely relate to how you connected psycological and spiritual theories here!
Personally, I believe in animism (so animals, plants, microorganisms, natural spiritually significant objects like rocks and natural phenomenon like lightning can all have souls), and I also believe souls can have limitless lives.
I think souls have their own preferred forms, so one soul might only reincarnate into one sole species, or another may only reincarnate into predatory mammals or creatures in the animal Kingdom, or maybe just plants, etc.
But aside from my spirituality, I think I have my specific theriotypes and connections because I was able to connect with them through my current life.
I was exposed to a very nature-loving family, I had cats around me since I was born, I watched media with a lot of specific animals, and this exposure made me imprint on certain animals! Then, this imprinting almost opened up the gate to my spiritual world, yknow?
But of course I still believe I was innately meant to be an animal because my souls preferance includes canines and felines, but my identity was certainly elevated by the world around me.
Sooo it's kind of like a mix of nature and nurture for me!
But anywho, I'm yapping- I really liked your thread :3
See ya around!