From the Galapagos Islands to New Zealand, species of birds that exist today model characteristics of their ancestors that provide clues to the environmental forces that shaped their evolution.

Over the course of 14 years, the authors carefully analyzed the skull, including the use of X-ray microscopy to create a 3D model. Its features don't slot neatly into any modern bird family.

A 69-million-year-old skull found in Antarctica has been identified as a relative of geese and ducks, making it the oldest known modern bird. It belongs to a species that was first identified two ...