Biotypes are defined by Dr Ian D’Agata (2014, p.567) as grapevines which despite being genetically identical to others do nevertheless present ‘enough morphological [the study of the form and structure of organisms and their specific structural features] and behavioural diversity to be viewed as a separate sub-varieties of the same family.’ Biotypes or sub-varieties are grapevines that share the same genetic background, yet, due to an adaptation to di!erent environments over a long period of time, they manifest morphological and physiological di!erences due to minor changes in the genotype occurring over time. These changes, however, are so minimal that they are not readily picked up on most genetic analysis. Examples of this mutability would include having di!erent berry sizes and color along with having a di!erent yielding potential and varied levels of disease susceptibility. In light of this, it is more accurate to refer to Favorita, Pigato, and Vermentino as biotypes rather than identical varieties. Many scientists are now increasingly championing this viewpoint.