P. gallinacea simply buried its eggs in warm sand or soil, just as some living megapodes in Indonesia and the Pacific still do. ... Some of the older specimens were first collected in the late 1800s; the newer ones came from the remarkable Thylacoleo caverns of Western Australia... These birds all lived in the Pleistocene - a time period that covers 11,700 years ago to 2.5 million years ago. That means they would have existed alongside some of the iconic megafauna - such as the giant marsupials - that disappeared shortly after modern humans first entered the Australian continent. Although...