This goes along with the skeletal system. I think my favorite trait in this is the duel syrinx. That's right. This gryphon can, not only, hold conversations with itself complete with interuptions but can also sing duets with itself. Note the four air sacs that help keep the respretory system rather like a radiator to keep cold air from high altitudes from scoring the lungs. The Interclavicular air sacs extend into the humerus of the wing. This is found in most bird species today. I made the brain rather large because of Mercedis Lackey's gryphons. They are intelligent, reasoning beings. As with most species of birds, this female gryphon has only one gonad located on the left side of her body to produce rather large eggs. Respectively, males would have only one testes on the left hand side. Should he carry an intermitant organ it would curve toward the left to better access the female's reproductive tract. While females are laying they would be quite grounded leaving the male to feed her and thus promote social bonds between the genders.