Xen- (prefix): Foreign or other. As in: 1  Xenoantigen -- An antigen that is found in more than one species.  Xenograft -- A surgical graft of tissue from one species to an unlike species, genus or family.
Diet. Snow Geese feed almost exclusively on plant material. During the breeding season, they eat many seeds, leaves, and roots of aquatic vegetation. The very young birds feed on invertebrates. Berries become more important in the fall. In winter, waste grain from agricultural fields has become a primary food source.
For other uses, see Goose (disambiguation) . Geese are waterfowl belonging to the tribe Anserini of the family Anatidae. This tribe comprises the genera Anser (the grey geese), Branta (the black geese) and Chen (the white geese).A number of other birds, mostly related to the shelducks, have goose as part of their names.his tribe comprises the genera Anser (the grey geese), Branta (the black geese) and Chen (the white geese). A number of other birds, mostly related to the shelducks, have goose as part of their names.