Mammals of Australia introductions of placental mammals into Australian fauna were about (rats), several thousand years ago (dingo), and 200 years ago (many species); the last two were made by humans. Some claims were made about placental mammal fossils from the Eocene of Australia, called "Tingamarra". These claims are based on only one found tooth having some characteristic features of condylarth, and were discussed widely. But both the age and placental nature of these fossils were challenged by other researchers. Monotremes are mammals with a unique method of reproduction: they lay eggs instead of giving birth to live young. Two of the five
Saint Bathans mammal adzebills are represented by unnamed species, as are various representatives of groups such as waterfowl, flamingos, rails, herons, strigopoidean parrots and even an early kiwi, "Proapteryx". However, unlike modern New Zealand it also had a varied herpetofauna: besides an early tuatara, the Saint Bathans fauna also includes meiolaniid and pleurodire turtles and possiblymekosuchine crocodiles and snakes. Besides the Saint Bathans mammal, this fauna also includes mystacine bats, a group still present in modern New Zealand. Like the modern species, these were probably terrestrial foragers, the same general ecological niche proposed for the Saint Bathans mammal. Other bats, including a vesper