Pitohui

The pitohuis are birds endemic to New Guinea. All six species were formerly classified in the Pitohui genus, classified in the same family. Two species are now classified in the Oriolidae, and three species in the Pachycephalidae (there is one species incertae sedis).

Most taxonomists now separate the species as follows:

Oriolidae

Pachycephalidae

Incertae sedis

They 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). These are believed to serve the birds as a chemical defence, either against ectoparasites or against visually guided predators such as snakes, raptors or humans.[1] The birds probably do not produce batrachotoxin themselves. The toxins most likely come from the beetle genus Choresine, part of the birds' diets.[2] Due to their toxicity, Papua New Guineans call the pitohuis rubbish birds as they are not good for eating; in desperate times, though, they can be consumed but only after the feathers and skin are removed and the flesh is coated in charcoal and then roasted. (Piper, 2007)

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 20 subspecies with different plumage patterns have been named. Two of them, however, closely resemble the hooded pitohui.

The birds' bright colours are suggested to be 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 an encounter with either species trains a predator to avoid both.[3]

See also

References

  1. (Dumbacher, et al., 1992)
  2. (Dumbacher, et al., 2004).
  3. (Dumbacher & Fleischer, 2001)

External links

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