1. Bird Skull Collection - http://skullsite.com 2. Skull Anatomy -http://www.cetus.ucsd.edu/SIO133/PDF/Skull%20Anatomy.pdf 3. Skull Structure Function - https://www.calacademy.org/skull-stories 4. Carnivore Skulls - http://www.nhc.ed.ac.uk/index.php?page=493.172 5. Sea Otter skull - http://www.burkemuseum.org/blog/robust-jaws-and-crushing-bites-allow-sea-otters-specialize-their-diets 6. Digital Morphology - http://digimorph.org/index.phtml