Megafauna is a word that simply means ‘large animals’ or ‘big animals’. It’s a way of describing animals based on their size rather than any relationships they might have to each other. They can be things like these mammals or large birds or reptiles as well.
There were many more very large animals or megafauna in the past and we’ve noticed by looking at the fossils that around about 2 million years ago, very large animals were very much more common than they are today. We still have very large animals today, things such as elephants and bison, but around 2 million years ago, this is quite some time after the death of the dinosaurs, there were very large animals roaming the Earth and these were in Europe - in Europe they had things like woolly mammoths and rhinos wandering around. In North and South America, we had things such as Smilodon here - the Sabre-tooth Tiger, and even here in Australia we had our own megafauna or very large animals, things like Diprotodon which you can see on display in the exhibition.
This is the jaw from a large male Diprotodon that was found in Lancefield. Other animals that were quite unfamiliar or have no living relative today were thing like this Thylacoleo. This is an animal that would have been feeding on other herbivore animals of the day, so this is the marsupial carnivore of Australia from about 1 or 2 million years ago and it had these large ‘bolt-cutting’ teeth that would have sheared through the limb bones of things like kangaroos and wallabies.
The megafauna went extinct sometime between 50,000 to 10,000 years ago. As to what caused the large megafauna to die off; we don’t really know. There are a number of different the theories and there’s quite a bit of debate going on about what some of the factors might have been – climate, changes in climate might have had a role, the spread of diseases might have caused these large animals to die off, and also humans – the migration of humans across the different land masses roughly ties in with the time these animals died out.
The more fossils that we find, and the more sites that we find that yield these sorts of fossils, these megafauna fossils, will help us get more clues about what might have made them go extinct and give us some ideas about the trends of extinction of large animals.