Degrees in order to work as a photographer?

When I'm older, I want to work as a photographer. I'd love to work for National Geographic, but I'm not sure how realistic that is. I'm not exactly sure what type of photographer I'd like to be, but I'd like to work with wildlife photography and possibly photography of people. I'm not interested in fashion photography, I'd like to be as active with the environment and nature as possible. Is there any degrees that would be useful in order to pursue a career in photography?