A
glycogen body is an oval structure in the
spinal cord of
birds that is made of specialized
cells that contain large amounts of
glycogen. The function of this structure
is not known, but it does not seem to be related to the normal function of glycogen in animals, which is the storage of energy. Glycogen bodies may also have been present in some
dinosaurs and are possibly the explanation for the structure that was once thought to be a "second brain" in animals such as
Stegosaurus.