Sixty-six million years ago, at the end of the Cretaceous Period, an asteroid impact near the Yucatán Peninsula of Mexico triggered the extinction of all known non-bird dinosaurs. But for the early ancestors of today’s waterfowl, surviving that mass extinction event was like…water off a duck’s back. Sixty-six million years ago, at the end of the Cretaceous Period, an asteroid impact near the Yucatán Peninsula of Mexico triggered the extinction of all known non-bird dinosaurs. But for the early ancestors of today’s waterfowl, surviving that mass extinction event was like…water off a duck’s back. Paleontology & Fossils Phys.org – latest science and technology news stories