Northern rockhopper penguin been caused by a vicariant event caused by a shift in the position of the Subtropical Front during the mid-Pleistocene climate transition. Analysis of a part of a mitochondrial control region from a northern rockhopper penguin found on the Kerguelen Islands showed that it may have come from Gough Island, 6,000 km away, and that the southern and northern rockhoppers are genetically separate, though some individuals may disperse from their breeding colonies. Many taxonomists have yet to recognize the split, although some are beginning to do so. More than 99% of northern rockhoppers breed on Tristan da Cunha and Gough
The Bird Lover the lai develops somewhat differently: instead of a happy ending, the lai ends in tragedy. A "sophisticated rationalization" of the type is found in Chrétien de Troyes's "Lancelot, the Knight of the Cart", where Lancelot appears at Guinevere's heavily barred window and cuts his fingers bending the bars back. In French scholarship, this type is often referred to as ""loiseau bleu"" or "the blue bird", so named for a story by Madame d'Aulnoy. The Bird Lover The Bird Lover, also known as The Prince as Bird, is a type of narrative structure in folklore, no. 432 in the Aarne–Thompson classification