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Male Satin BowerbirdPtilonorhynchus violaceus
Male Satin Bowerbird
Ptilonorhynchus violaceus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Suborder: Passeri
Family: Ptilonorhynchidae
GR Gray, 1841


This article is about the family of birds called bowerbirds. For the band, see Bowerbirds (band).

Bowerbirds (IPA: /ˈbaʊərˌbɜrd/) and catbirds make up the bird family Ptilonorhynchidae. The family has 20 species in eight genera. These are medium-sized passerines, ranging from the Golden Bowerbird (22 cm and 70 grams) to the Great Bowerbird (40 cm and 230 grams). Although their distribution is centered around the tropical northern part of Australia and New Guinea, some species extend into the central, western and SE regions of Australia. Their diet consists fruit, but may also include insects (fed to young), flowers, nectar and leaves in some species.[1]

The bowerbirds have an Austro-Papuan distribution, with ten species being endemic to New Guinea, eight species being endemic to Australia and two species being found in both.[2] They occupy a range of different habitats, including rainforest, eucalypt and acacia forest and woodland and shrublands.


[edit] Mating behaviour

Bower of a Satin Bowerbird

The catbirds are monogamous and raise chicks with their mate, but all other bowerbirds are polygynous, with the female building the nest and raising the young alone. These latter species are commonly sexually dimorphic, with the female being more drab in color. Female bowerbirds build nest by laying soft materials, such as leaves, ferns, and vine tendrils on top of a loose foundation of sticks. They lay one or two eggs, which hatch after 19 to 24 days, depending on species.[1]

The most notable characteristic of bowerbirds is their extraordinarily complex courtship and mating behaviour, males build a bower to attract mates. There at two main types of bowers. One clade of bowerbirds build so-called maypole bowers that are constructed by placing sticks around a sapling, in some species these bowers have a hut-like roof. The other major bowerbuilding clade builds an avenue type bower made of two walls of vertically placed sticks. In and around the bower the male places a variety of brightly colored objects he has collected. These objects — usually different among each species — may include hundreds of shells, leaves, flowers, feathers, stones, berries, and even discarded plastic items, coins, nails, rifle shells, or pieces of glass. The males spend hours arranging this collection. Bowers within a species share a general form but do show sigificant variation, and the collection of objects reflects the biases of males of each species and its ability to procure items from the habitat often stealing them from neighboring bowers. Several studioes of different species have shown that colors of decorations males use on their boewers match the preferences of females.

Uy and collaborators have shown that mate searching females commonly visit multiple bowers, often returning to the male several times, watching as the male owner's elaborate courtship displays and inspecting the quality of the bower and tasting the paint the male has placed on the bower walls. Many females end up selecting the same male, and many under-performing males are left without copulations. Femals mated with top mating males tend to retutn to the male the next year and search less.

Gilliard has suggested the "transfer effect," in which he claimed that bowerbird species that build the most elaborate bowers are dull in color and show little variation between male and female, whereas in bowerbird species with less elaborate bowers the males have bright plumage. This hypothesis is not well supported because species with vastly different bower types have similar plumage. Borgia has suggested that the bower functioned initially as a device that benefits females by protecting them from forced copulations and thus giving them enhanced opportunity to choose males, and benefits males by enhancing female willingness to visit the bower. Evidence supporting this hypotheis comes from observations of Archbold's bowerbirds that have no true bower and have greatly modified their courtship so that the male is limited in his ability to mount the female without her cooperation. In toothbilled bowerbirds that have no bowers males may capture females out of the air and forcably copulate with them. Once this initial function was established bowers were then co-opted by females for other functions such as use in assesing males based on the quality of bower construction. Recent studies with robot female bowerbirds by Patricelli and collaborators have shown that males react to female signals of discomfort during courtship by reducing the intensity of their potentially threatening courtship. Coleman and colleagues found that young females tend to be more easily threatened by intense male courtship, and these females tend to choose males based on traits not dependent on male courtship intensity. The high degree of effort directed at mate choice by females and the large skews in mating success directed at males with quality displays suggests that females gain important benefits from mate choice. Since males have no role in parental care, give nothing to females except sperm it is suggested that females gain genetic benefits from their mate choice but this has not been established, in part, because of the difficulty of following offspring performance because males take seven years to reach sexual maturity.

This complex mating behaviour, with highly valued types and colors of decorations that, has led some researchers[who?] to regard the bowerbirds as among the most behaviorally complex species of bird. It also provides some of the most compelling evidence that the extended phenotype of a species can play a role in sexual selection and indeed act as a powerful mechanism to shape its evolution, as seems to be the case for humans.

In addition, many species of bowerbird are superb vocal mimics. Macgregor's Bowerbird, for example, has been observed imitating pigs, waterfalls, and human chatter. Satin bowerbirds commonly mimic other local species as part of their courtship display.

[edit] Relationships

Though bowerbirds have traditionally been regarded as closely related to the birds of paradise, recent [[molecular}]] studies suggest that while both families are part of the great corvid radiation that took place in or near Australia-New Guinea, the bowerbirds are more distant from the birds of paradise than was once thought. Sibley's DNA-DNA hybridization studies placed them close to the lyrebirds[citation needed]; however, anatomical evidence appears to contradict this placement[citation needed] and the true relationship remains unclear. Note that the Gray Catbird (Dumetella carolinensis) and Black Catbird (Melanoptila glabrirostris) from the Americas and the Abyssinian Catbird (Parophasma galinieri) from Africa are unrelated birds that belong to different families.

[edit] Distribution and habitat

[edit] Systematics

Genus Ailuroedus

Genus Scenopooetes

Genus Archboldia

Genus Amblyornis

Golden Bowerbird male (top) and female

Genus Prionodura

Genus Sericulus

Genus Ptilonorhynchus

Genus Chlamydera

Note that the Gray Catbird (Dumetella carolinensis) and Black Catbird (Melanoptila glabrirostris) from the Americas and the Abyssinian Catbird (Parophasma galinieri) from Africa are unrelated birds that belong to different families.

[edit] Distribution and habitat

[edit] References

  1. ^ a b Frith, Clifford B. (1991). Forshaw, Joseph. ed. Encylcopedia of Animals: Birds. London: Merehurst Press. pp. 228–331. ISBN 1-85391-186-0. 
  2. ^ Rowland, Peter (2008). Bowerbirds. Australian Natural History Series. Collingwood: CSIRO Publishing. pp. 1-26. ISBN 978-0-643094-20-8. 

[edit] External links

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