All Magic is Academic

You have developed an understanding of magic that all magic is just different expressions of the same natural phenomena. You know that wild shape is nothing more then a specialized polymorphic spell in essence. You can learn to use a wild shape from studying the creature from a book. If you study the traits and characteristics of a creature for a long rest you can wild shape into that creature. The challenge rating of the creature you are able to understand is equal to your intelligence modifier.