Morphological variation includes aspects of the outward appearance i.e shape, structure, color, pattern, size which is in contrast to physiology variation which deals primarily with function.
Morphological variation arises from a number of factors which can be bluntly classified as either genetic or environmental implanted into the process of evolution.
Discontinuous variation is variation that has distinct groups for organisms to belong to i.e tongue rolling, finger prints, eye color, blood groups