Canada Goose

# Evolutionary Timeline of the Canada Goose The Canada Goose (*Branta canadensis*) belongs to the family Anatidae, with roots tracing back to ancient waterfowl. Its evolution was shaped by climatic shifts, habitat changes, and the need for migration. Key milestones include: - **Late Cretaceous ( ~70-66 million years ago)**: Ancestors of Anseriformes (waterfowl) emerge among early modern birds, surviving the mass extinction event. - **Paleogene Period ( ~66-23 million years ago)**: Diversification of duck-like birds in wetland environments, driven by post-extinction ecological opportunities. - **Miocene Epoch ( ~23-5 million years ago)**: Emergence of true geese (tribe Anserini), with adaptations for grazing and flight in response to grassland expansion. - **Pliocene-Pleistocene ( ~5 million years ago to present)**: Divergence of the genus *Branta*, including the Canada Goose, influenced by ice ages that promoted migratory behaviors and cold tolerance. Environmental pressures like glaciation and habitat fragmentation selected for strong flying abilities, social flocking, and versatile feeding habits.