Board Thread:General Discussion/@comment-24198837-20140421023639/@comment-24400457-20140423200824

I doubt it. Most of the genetic make up may be stored in a single, or a select group of genes, much like how eye colour is dictated. Canine, feline and primate archtypes, "Rabbit" and "Bear" Faunus could, for example all be caused by "dominant" genes (akin to Brown eyes) whilst Reptile, snake and bird archtypes, Mouse, Moose and wolverine could all be caused by "recessive" genes (akin to Blue eyes). Basically Dog and Cat Faunus could share the same chromosomes and genes in general, it's just that their alleles have incredibly significant effects as opposed to the ranging potential genetics a human could have.

Honestly I don't see such a thing being clarified, the same with whether or not Faunus and Humans can mate (I imagine they can similar to donkies and horses producing mules or tigers and lions producing ligers). The only time we could see evidence of such a thing is if they decide to have say Blake or Weiss give birth to a crossbreed at some point (a possibility if they want to use some kind of timeskip or flash forward towards the end of the series to show Future!RWBY) or if they introduce a half-Faunus half-human character. It's also possbile that they could off-handedly note that Blake's father was a wolf-Faunus or Sun's mother was a fox-Faunus to establish it.

They'll probably never go in-depth so I'd say accept "they can" as head canon since they probbably won't ever falsify that assumption, and if you don't want to depict such relationships in fan work then simply don't... or attach "AU" or "AR" to your description.