Why is the Southern Hemisphere important to the early evolution of Anseriformes?

The Southern Hemisphere is considered significant to the early evolution of the order Anseriformes because it is the likely site where the diversification of these birds began.1

This region remains home to many endemic and monotypic genera, as well as ancient and primitive lineages such as the magpie goose and screamers. These groups provide important insights into the evolutionary history of the order, as they retain features similar to the unspecialized, long-legged ancestral forms that existed more than 65 million years ago.1