Diatryma gigantea

This extinct bird grew as tall as a basketball player and weighed over 150 kilograms (330 pounds)! It also had heavy legs and tiny wings. Of course, this big bird couldn't fly. Diatryma fossils have been found in North America and Europe, from a time 10 million years after the extinction of most dinosaurs.

Image credits: main image, Rick Spears; stumper, © AMNH.