Tongan megapode Tongan megapode The Tongan megapode ("Megapodius pritchardii") is a species of bird in the megapode family, Megapodiidae, currently endemic to Tonga. The species is also known as the Polynesian megapode, and as the Niuafo'ou megapode after the island of Niuafo'ou to which it was restricted for many years. The specific epithet honours British consul William Thomas Pritchard. The Tongan megapode is the only remaining species of megapode in Tonga out of the four or five species that were present on the islands in prehuman times (as shown through the fossil record), and indeed the only species of megapode that survives
Megapode was thought to exhibit temperature-dependent sex determination, this was later proven false; temperature does, however, affect embryo mortality and resulting offspring sex ratios. The nonsocial nature of their incubation raises questions as to how the hatchlings come to recognise other members of their species, which is due to imprinting in other members of the order Galliformes. Research suggests an instinctive visual recognition of specific movement patterns is made by the individual species of megapode. Megapode chicks do not have an egg tooth; they use their powerful claws to break out of the egg, and then tunnel their way up to