Throughout much of the 19th century, reports of some unknown animal called the ‘Australian gorilla’ or ‘yahoo’ regularly emerged from the south-east corner of Australia, but were largely ignored by scientists of the day. On the two occasions when the existence of the animal did become the object of scientific attention, the real issues were marginalised.In recent years the matter has been subjected to renewed debate, yet it is still poorly understood. Indeed, some years ago an academic acquaintance of mine with an interest in the matter told me of a revealing remark made to him by a scientist at The Australian Museum. The remark to my friend was along the lines that ‘Surely you at least understand that there have never been gorillas in Australia.’Now it would be impossible to quarrel with this point of view. Australia is a land of marsupials while the gorilla is a placental animal which, except for a few in zoos, is found only in Africa. And similarly for the other large apes. Yet, paradoxically, I am going to suggest we might reasonably entertain the hypothesis that there have been ‘Australian gorillas’. How is this possible?Another, more famous, paradox may throw light on this one. Since its introduction to Europeans in the late 18th century, the platypus has been an almost endless source of wonder. Umberto Eco, Professor of Semiotics at Bologna, has recently brought together various theoretical considerations to explain the amazement generated in scientific circles by this strange animal. In his book ‘Kant and the Platypus’, Eco asks what would Kant have made of the platypus?, although Eco might have chosen any number of other Australian animals to make his point.