Among mammals, early extinct species laid eggs, as do platypuses and echidnas (spiny anteaters). Platypuses and two genera of echidna are Australian monotremes. However, the five species of monotreme, the platypuses and the echidnas, lay eggs. Other animals present in the IBA include platypuses, short-beaked echidnas and Richmond birdwings. Animal species such as kangaroos, dingoes, tiger, bandicoots, gliders and platypuses were common. The glans penis is also divided into two parts in platypuses and echidnas. Lyrebirds, wombats, swamp wallabies, gliders and platypuses can also be found within the park. The lyrics mention animals and objects associated with Australia, including cockatoos, koalas, platypuses, and didgeridoos. Gorillas and chimpanzees use this style of locomotion as do anteaters and platypuses. Other semi-aquatic mammals include beavers, hippopotamuses, otters and platypuses. Giant anteaters and platypuses are also knuckle-walkers. Scientists generally use "platypuses" or simply "platypus". The tribosphenic tooth is found in insectivores and young platypuses (adults have no teeth). Mount Emu Creek abounds in redfin and is the home of many platypuses. Adult male platypuses largely avoid each other, outside of this mating rivalry.