User blog comment:Hidden Scorpius XI/My impressions on "A Much Needed Talk" (V4-E8)/@comment-4010415-20170102004223/@comment-70.196.134.219-20170102032158

I'm personally fond of the theory that Faunus were a failed experiment to avoid the Grimm. We know that normals animals aren't really targeted by the Grimm unless they impose on their territory (perhaps a small comfort considering they basically own the planet) so ancient humans tried splicing some of their own people with animals to try and fool the Grimm.

It obviously didn't work, but it could set the groundwork for human/Faunus animosity. Humans might see the Faunus as a failed lab experiment and the Faunus see humans as psychos who greatly changed them and then ostrocized them after their experiment failed.

Years down the line, neither side remembers the specifics, but the old hatred still remains.

Of course, that's just a theory that I've seen tossed around and I'm fond of.