Barnacle goose were of the same nature as other birds. The question of the nature of barnacle geese also came up as a matter of Jewish dietary law in the Halakha, and Rabbeinu Tam (1100–71) determined that they were kosher (even if born of trees) and should be slaughtered following the normal prescriptions for birds. The mythical barnacle tree, believed in the Middle Ages to have barnacles that opened to reveal geese, may have a similar origin to the other legends already mentioned. Barnacle goose The barnacle goose ("Branta leucopsis") belongs to the genus "Branta" of black geese, which contains species with
Branta thessaliensis range disjunction is less pronounced in the Canada and cackling geese of North America, where unlike in there was no W-E barrier (the Alpide belt) barring range shifts in response to the advancing ice. Branta thessaliensis Branta thessaliensis is a prehistoric species of black goose known from fossils found in Greece. It is among the earliest known members of its genus. Described in 2006, it was of similar size to the Canada goose. It is known from a humerus bone, which differs form the living species by a wider distal end of the diaphysis, a dorsal condyle that is more