I agree with all the above_ you don't need to consider body parts and materials as the same things_ just use the assign material option in Poser or a mapper such as UVMapper. From a poseability point of view I would be inclined to have the upper beak section as part of the head (and therefore fixed) and the lower section of the beak and the tongue each as seperate body parts that you can pose_ it would look more natural. Great modelling btw!