Dragon Identification
Scientists use structural features to differentiate organisms. I classify dragons according to how many wings (first), legs (second), & heads (third) they have. Some dragons are in a grouping between reptile & bird (Quetzalcoatl, Cockatrice), others reptile & fish (Moo), and in rare cases reptile & mammal (Falco the Luck Dragon in “The Never Ending Story”). I theorize that in the case of multi headed wyverns and Western dragons that it is a case of a recessive gene giving the dragon a survival advantage. Those dragons thus gifted become more notorious. Some are now a species unto their own, such as Zmaj, being confused with those that are newly gifted with extra heads. In a similar manner extra tails come about but I do not give them their own classifications.
Many modern breeds of Western & wyvern have come about no doubt through the intervention of Mages using their magic to genetically alter the original (chromatic, metallic, & those showcased in “Harry Potter”)