Talk:Mershark/@comment-29693921-20170203162726/@comment-10429980-20170204012724

One possibility is that animals do not run on mana the same way humans do. Any mana they have could be energy they take in from the environment, they wouldn't have an inner mana system to damage, and as such her teeth would work like normal on them. This is based on how mamono realm silver weapons and mershark teeth work like normal objects when they are used on things that don't run on mana like chains or the hull of a ship. Admittedly that idea has some holes in it. Animals may well produce mana, as we know they at least are effected by it (i.e. it causes mamono realm beasts to develop) and some even use it (like the shelled bugs).

Alternatively, and perhaps a better idea, the mana-damaging effect is specialized to work only on humans (and perhaps other monsters). Note that her scales and teeth are stated to have the same properties as the silver, but not to actually be the silver. Ergo they may be specialized to distinguish human prey from animal prey. Indeed the profile only specifies that humans are not physically damaged, not that animals are not.