During the Pleistocene, the megafauna was diverse all over the world. Most continental ecosystems had similar or greater biodiversity in megafauna than modern African ecosystems. During the late Pleistocene, however, most of the large mammals and other megafauna species (reptiles, birds) became extinct, while smaller animals were largely unaffected. The so-called Late Pleistocene megafauna extinction started at different times on different continents or islands, and the proportion of extinct megafauna species to the total fauna varied too. The course (pattern) of extinctions was similar across continents, i.e. there was a period when the majority of megafauna species became extinct within a short period of time, while some species disappeared earlier and others later.
For example, in Australia and the surrounding islands, megafauna species began to disappear about 50 000 years ago, in Europe about 25 000 years ago and in North America about 14 000 years ago. Mass extinctions, however, occurred later: around 40 000 years ago in Australia and the surrounding area, around 12 000 in Europe and around 11 000 in North and South America. There is much debate about whether the end of the Pleistocene is the Sixth Great Extinction; many researchers believe that the five previous great extinctions in Earth’s history (e.g. the end of the Cretaceous, when dinosaurs, among others, became extinct) were of a much larger scale and cannot be compared to the end of the Pleistocene.