Pitohui
The Pitohuis are a genus of birds, endemic to New Guinea, belonging to the family Pachycephalidae. Currently six species are classified in the genus, though current molecular genetics research suggests that significant reclassification of the Pachycephalidae may be needed. Species currently recognised are: Variable Pitohui Pitohui kirhocephalus Hooded Pitohui Pitohui dichrous White-bellied Pitohui, Pitohui incertus Rusty Pitohui Pitohui ferrugineus Crested Pitohui Pitohui cristatus Black Pitohui Pitohui nigrescens Pitohuis are brightly coloured, omnivorous birds. The skin and feathers of some pitohuis, especially the Variable and Hooded Pitohuis, contain powerful neurotoxic alkaloids of the batrachotoxin group (also secreted by the Colombian poison dart frogs, genus Phyllobates). It is believed that these serve the birds as a chemical defence, either against ectoparasites or against visually guided predators such as snakes, raptorss or humans. The Hooded Pitohui is brightly coloured, with a brick red belly and a jet black head. The Variable Pitohui, as its name implies, exists in many different forms, and twenty subspecies with different plumage patterns have been named. Two of them, however, closely resemble the Hooded Pitohui. It has been suggested that the birds' bright colours are an example of aposematism (warning colouration), and the similarity of the Hooded Pitohui and some forms of the Variable Pitohui might then be an example of Müllerian mimicry, in which dangerous species gain a mutual advantage by sharing colouration, so that an encounter with either species trains a predator to avoid both.
ReferencesDumbacher, J. P., Beehler, B. M., Spande, T. F., Garaffo, H. M., & Daly, J. W. (1992). Homobatrachotoxin in the genus Pitohui: Chemical defense in birds? Science 258: 799-801.Dumbacher, J. P., & Fleischer, R. C. (2001). Phylogenetic evidence for colour pattern congervence in toxic pitohuis: Müllerian mimicry in birds? Proceedings of the Royal Society of London series B 268: 1971-1976.
External linkFUGU, POISON FROGS, AND PITOHUIS by Harold B. White
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