Taiga bean goose

The taiga bean goose is a species of goose that breeds in northern Europe and Asia and migrates south to winter further across the continent. It and the tundra bean goose were recognized as separate species by the International Ornithologists Union and the American Ornithological Society from 2007 onward, though some other authorities, notably BirdLife International and the IUCN, still treat them as a single species. The two lineages are estimated to have diverged about 2.5 million years ago before establishing secondary contact around 60,000 years ago, with extensive gene flow between them. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/