In a fantastic world of magic, it can be assumed magic is in all living creatures to some degree, and a part of it is with concentration usable for magical purposes - humanoids are typically such users.

It is only logical, that for instance animals should have this magic, too.

"I walked through the poor's quarters, and my eye was not harmed. All functional, and simple, and crude, made on the whims of fate and delivered by immediate need.
I walked through the merchant's quarters, and my eye was bored. Pretensions where nothing backed them, striving for appearance without substance, evidence of changing wealth, too much only began, too much never finished.
I walked through the place where the powerful lived, and my eye was tired. Too much of attempted beauty turned hideous, and a lack of taste was made worse by willing lackeys.
But then I've seen the treasure of the city. A cathedral, that was part of the sky, columns, and arches to carry the weight of the world, shapes to let your mind fly along, and ornaments to stop by. A place to ponder, to be pleased to be alive, to accept suffering, and to realize your mistakes. This is a place I could learn from."