Oh, I've read some books about a bunch of kids who were able to do that when I was little.
After they touched an animal, they were able to shapeshift into it. They could only stay in the shapeshifted form for a while though, otherwise they would not be able to change back(they can still think like humans, but are stuck in the body of the creature they shapeshifted in).

Would the shapeshifting be something that has to be learned or a skill that is automatically gained at birth/ a certain age?

If people are able to shapeshift, I think it would be believable they also have some basic form of communing with nature, but no control over elements, creation of illusions or whatsoever.

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