Bowerbird
Encyclopedia
Bowerbirds make up the bird family
Ptilonorhynchidae. The family has 20 species in eight genera
. These are medium-sized passerine
s, ranging from the Golden Bowerbird
(22 cm and 70 grams) to the Great Bowerbird
(40 cm and 230 grams). Their diet consists mainly of fruit but may also include insects (fed to young), flowers, nectar and leaves in some species.
The bowerbirds have an Austro-Papuan distribution
, with ten species endemic to New Guinea
, eight endemic to Australia and two found in both. Although their distribution is centered around the tropical regions of New Guinea and northern Australia, some species extend into central, western and southeastern Australia. They occupy a range of different habitats, including rainforest
, eucalyptus
and acacia
forest, and shrublands.
Bowerbirds are most known for their unique courtship behaviour, where males build a structure and decorate it with sticks and brightly coloured objects in an attempt to attract a mate.
s are monogamous and raise chicks with their mate, but all other bowerbirds are polygamous
, 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 a 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 the species.
The most notable characteristic of bowerbirds is their extraordinarily complex courtship and mating behaviour, where males build a bower to attract mates. There are two main types of bowers. One clade of bowerbirds build so-called maypole bowers, which 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 significant 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 studies of different species have shown that colors of decorations males use on their bowers 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 his 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. Females mated with top-mating males tend to return 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 hypothesis 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 forcibly copulate with them. Once this initial function was established, bowers were then co-opted by females for other functions such as use in assessing 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 and 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 its highly valued types and colors of decorations, has led some researchers 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.
Bower birds have also been observed creating optical illusion
in their bowers to appeal to mates. They arrange objects on the avenue from smallest to largest, creating a forced perspective
that makes the male appear very large.
's DNA-DNA hybridization studies placed them close to the lyrebird
s; however, anatomical evidence appears to contradict this placement, 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.
Genus Ailuroedus
Genus Scenopooetes
Genus Archboldia
Genus Amblyornis
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.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Ptilonorhynchidae. The family has 20 species in eight genera
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
. These are medium-sized passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
s, ranging from the Golden Bowerbird
Golden Bowerbird
The Golden Bowerbird, Prionodura newtoniana is a species of bowerbird found in the rainforests above 700m of Atherton, Queensland in Australia...
(22 cm and 70 grams) to the Great Bowerbird
Great Bowerbird
The Great Bowerbird, Chlamydera nuchalis is a common and conspicuous resident of northern Australia, from the area around Broome across the Top End to Cape York Peninsula and as far south as Mount Isa...
(40 cm and 230 grams). Their diet consists mainly of fruit but may also include insects (fed to young), flowers, nectar and leaves in some species.
The bowerbirds have an Austro-Papuan distribution
Range (biology)
In biology, the range or distribution of a species is the geographical area within which that species can be found. Within that range, dispersion is variation in local density.The term is often qualified:...
, with ten species endemic to New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, eight endemic to Australia and two found in both. Although their distribution is centered around the tropical regions of New Guinea and northern Australia, some species extend into central, western and southeastern Australia. They occupy a range of different habitats, including rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
, eucalyptus
Eucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
and acacia
Acacia
Acacia is a genus of shrubs and trees belonging to the subfamily Mimosoideae of the family Fabaceae, first described in Africa by the Swedish botanist Carl Linnaeus in 1773. Many non-Australian species tend to be thorny, whereas the majority of Australian acacias are not...
forest, and shrublands.
Bowerbirds are most known for their unique courtship behaviour, where males build a structure and decorate it with sticks and brightly coloured objects in an attempt to attract a mate.
Mating behavior
The catbirdCatbird
Several unrelated groups of songbirds are called catbirds because of their wailing calls, which resemble a cat's meowing. The genus name Ailuroedus likewise is from the Greek for "cat-singer" or "cat-voiced"....
s are monogamous and raise chicks with their mate, but all other bowerbirds are polygamous
Polygamy
Polygamy is a marriage which includes more than two partners...
, with the female building the nest and raising the young alone. These latter species are commonly sexually dimorphic
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
, with the female being more drab in color. Female bowerbirds build a 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 the species.
The most notable characteristic of bowerbirds is their extraordinarily complex courtship and mating behaviour, where males build a bower to attract mates. There are two main types of bowers. One clade of bowerbirds build so-called maypole bowers, which 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 significant 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 studies of different species have shown that colors of decorations males use on their bowers 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 his 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. Females mated with top-mating males tend to return 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 hypothesis 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 forcibly copulate with them. Once this initial function was established, bowers were then co-opted by females for other functions such as use in assessing 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 and 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 its highly valued types and colors of decorations, has led some researchers 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
The Extended Phenotype
The Extended Phenotype is a biological concept introduced by Richard Dawkins in a 1982 book with the same title. The main idea is that phenotype should not be limited to biological processes such as protein biosynthesis or tissue growth, but extended to include all effects that a gene has on its...
of a species can play a role in sexual selection
Sexual selection
Sexual selection, a concept introduced by Charles Darwin in his 1859 book On the Origin of Species, is a significant element of his theory of natural selection...
and indeed act as a powerful mechanism to shape its evolution
Evolution
Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...
, as seems to be the case for humans.
In addition, many species of bowerbird are superb vocal mimics. Macgregor's Bowerbird
Macgregor's Bowerbird
The Macgregor's Bowerbird, Amblyornis macgregoriae is a medium-sized, up to 26 cm long, olive brown bowerbird of New Guinea's mountain forests, roughly the size and shape of a robin. The male is adorned with an erectile orange yellow crest, that is partly hidden until shown in courtship...
, for example, has been observed imitating pigs, waterfalls, and human chatter. Satin Bowerbirds commonly mimic other local species as part of their courtship display.
Bower birds have also been observed creating optical illusion
Optical illusion
An optical illusion is characterized by visually perceived images that differ from objective reality. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus source...
in their bowers to appeal to mates. They arrange objects on the avenue from smallest to largest, creating a forced perspective
Forced perspective
Forced perspective is a technique that employs optical illusion to make an object appear farther away, closer, larger or smaller than it actually is. It is used primarily in photography, filmmaking and architecture...
that makes the male appear very large.
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. Charles SibleyCharles Sibley
Charles Gald Sibley was an American ornithologist and molecular biologist. He had an immense influence on the scientific classification of birds, and the work that Sibley initiated has substantially altered our understanding of the evolutionary history of modern birds.Sibley's taxonomy has been a...
's DNA-DNA hybridization studies placed them close to the lyrebird
Lyrebird
A Lyrebird is either of two species of ground-dwelling Australian birds, that form the genus, Menura, and the family Menuridae. They are most notable for their superb ability to mimic natural and artificial sounds from their environment. Lyrebirds have unique plumes of neutral coloured...
s; however, anatomical evidence appears to contradict this placement, and the true relationship remains unclear. Note that the Gray Catbird
Gray Catbird
The Gray Catbird , also spelled Grey Catbird, is a medium-sized northern American perching bird of the mimid family. It is the only member of the "catbird" genus Dumetella...
(Dumetella carolinensis) and Black Catbird
Black Catbird
The Black Catbird is a songbird species in the monotypic genus Melanoptila of the family Mimidae. At 24 grams and 20 cm, it is the smallest mimid.It is found in Belize, Guatemala, Honduras, and Mexico...
(Melanoptila glabrirostris) from the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...
and the Abyssinian Catbird
Abyssinian Catbird
The Abyssinian Catbird is a species of bird in the Timaliidae family. It is monotypic within the genus Parophasma.It is endemic to Ethiopia. Its natural habitat is subtropical or tropical dry forests.-References:...
(Parophasma galinieri) from Africa are unrelated birds that belong to different families.
Systematics
Ailuroedus
Ailuroedus is a genus of birds in the Ptilonorhynchidae family .-Species:* White-eared Catbird * Green Catbird * Spotted Catbird...
- White-eared CatbirdWhite-eared CatbirdThe White-eared Catbird is a species of bird in the Ptilonorhynchidae family.It is found in Indonesia and Papua New Guinea....
, Ailuroedus buccoides - Spotted CatbirdSpotted CatbirdThe Spotted Catbird, Ailuroedus melanotis, also known as Black-eared Catbird, is a species of bowerbird which can be found in north Queensland, Australia, and the island of New Guinea. It is approximately 26–30 cm in length, and its coloring is emerald green, with faint black markings on the...
, Ailuroedus melanotis - Green CatbirdGreen CatbirdThe Green Catbird, Ailuroedus crassirostris is a species of bowerbird found on subtropical forests along the east coast of Australia, from southeastern Queensland to southern New South Wales. Its colouring is emerald green, with faint black markings on the face and white streaks on the neck.Green...
, Ailuroedus crassirostris
Genus Scenopooetes
- Tooth-billed CatbirdTooth-billed CatbirdThe Tooth-billed Catbird, Scenopoeetes dentirostris also known as Stagemaker Bowerbird is a medium-sized, approximately 27 cm long, stocky olive-brown bowerbird with brown-streaked buffish-white below, a grey feet, brown iris and unique tooth-like bill. Both sexes are similar, however the...
, Scenopooetes dentirostris
Genus Archboldia
Archboldia
Archboldia is a genus of bowerbirds, in family Ptilonorhynchidae, bowerbirds and catbirds.-Species:*Archboldia papuensis - Archbold's Bowerbird.*Archboldia sanfordi - Sanford's Bowerbird.-External links:*...
- Archbold's BowerbirdArchbold's BowerbirdThe Archbold's Bowerbird, Archboldia papuensis is a medium-sized, up to 37 cm long, dark grey songbird with brown iris, grey feet and black bill. The male has narrow black scalloping with some trace of golden yellow crown feathers and dark grey forked tail, that shorter than the wing. Both...
, Archboldia papuensis - Sanford's BowerbirdSanford's BowerbirdThe Sanford's Bowerbird, Archboldia sanfordi is a black bowerbird with a reddish-brown iris, grey feet and black bill. The male has a golden crest extending from forehead, blackish wing and long tail. Both sexes are alike...
, Archboldia sanfordi
Genus Amblyornis
Amblyornis
The genus Amblyornis of the family Ptilonorhynchidae consists of four species of bowerbirds endemic to New Guinea.-Species:* Golden-fronted Bowerbird, Amblyornis flavifrons* Macgregor's Bowerbird, Amblyornis macgregoriae...
- Vogelkop BowerbirdVogelkop BowerbirdThe Vogelkop Bowerbird , also known as the Vogelkop Gardener Bowerbird, is a medium-sized, bowerbird of the mountains of the Vogelkop Peninsula at Western New Guinea, Indonesia.-Description:...
, Amblyornis inornatus - Macgregor's BowerbirdMacgregor's BowerbirdThe Macgregor's Bowerbird, Amblyornis macgregoriae is a medium-sized, up to 26 cm long, olive brown bowerbird of New Guinea's mountain forests, roughly the size and shape of a robin. The male is adorned with an erectile orange yellow crest, that is partly hidden until shown in courtship...
, Amblyornis macgregoriae - Streaked BowerbirdStreaked BowerbirdThe Streaked Bowerbird, Amblyornis subalaris is a species of bowerbird which can be found in southeastern New Guinea. They are approximately 22 cm long and have an olive-brown colouring. The male has a short orange crest which is not visible unless displayed.The Streaked Bowerbird is a...
, Amblyornis subalaris - Golden-fronted BowerbirdGolden-fronted BowerbirdThe Golden-fronted Bowerbird, Amblyornis flavifrons is a medium-sized, approximately 24 cm long, brown bowerbird. The male is rufous brown with an elongated golden crest extending from its golden forehead, dark grey feet and buffish yellow underparts...
, Amblyornis flavifrons
- Golden BowerbirdGolden BowerbirdThe Golden Bowerbird, Prionodura newtoniana is a species of bowerbird found in the rainforests above 700m of Atherton, Queensland in Australia...
, Prionodura newtoniana
Genus Sericulus
Sericulus
The genus Sericulus of the family Ptilonorhynchidae consists of three spectacularly colored bowerbirds.All three species build an "avenue-type" bower and are found in New Guinea and Australia.-Species:* Flame Bowerbird, Sericulus aureus...
- Flame BowerbirdFlame BowerbirdThe Flame Bowerbird, Sericulus aureus, is one of the most brilliantly coloured bowerbirds. The male is a medium-sized bird, up to 25 cm long, with flame orange and golden yellow plumage, elongated neck plumes and yellow-tipped black tail. It builds an "avenue-type" bower with two side walls of...
, Sericulus aureus - Fire-maned BowerbirdFire-maned BowerbirdThe Fire-maned Bowerbird, Sericulus bakeri is a medium-sized, approximately 27 cm long, bowerbird that inhabits and endemic to the forests of Adelbert Mountains in Papua New Guinea. The striking male is black with fiery orange crown and upperback, elongated neck plumes, yellow iris and golden...
, Sericulus bakeri - Regent BowerbirdRegent BowerbirdThe Regent Bowerbird, Sericulus chrysocephalus is a medium-sized, up to 25 cm long, sexually dimorphic bowerbird. The male bird is black with a golden orange-yellow crown, mantle and black-tipped wing feathers. It has yellow bill, black feet and yellow iris...
, Sericulus chrysocephalus
Genus Ptilonorhynchus
- Satin BowerbirdSatin BowerbirdThe Satin Bowerbird, Ptilonorhynchus violaceus is a bowerbird endemic to eastern Australia.A rare natural intergeneric hybrid between the Satin Bowerbird and the Regent Bowerbird is known as Rawnsley's Bowerbird.-Distribution:...
, Ptilonorhynchus violaceus
Genus Chlamydera
Chlamydera
Chlamydera is a genus of bird in the Ptilonorhynchidae family.-Species:All species found in Australia and/or New Guinea:* Fawn-breasted Bowerbird * Western Bowerbird...
- Western BowerbirdWestern BowerbirdThe Western Bowerbird is a species of bird in the Bowerbird family. The species is a common endemic of Australia. It has a disjunct distribution, occurring in Central Australia and the Pilbara region of Western Australia. There are two subspecies, the nominate, which occupies most of its range,...
, Chlamydera guttata - Spotted BowerbirdSpotted BowerbirdThe Spotted Bowerbird is a bowerbird widely distributed across inland Queensland and New South Wales.-Australia:...
, Chlamydera maculata - Great BowerbirdGreat BowerbirdThe Great Bowerbird, Chlamydera nuchalis is a common and conspicuous resident of northern Australia, from the area around Broome across the Top End to Cape York Peninsula and as far south as Mount Isa...
, Chlamydera nuchalis - Yellow-breasted BowerbirdYellow-breasted BowerbirdThe Yellow-Breasted Bowerbird, Chlamydera lauterbachi also known as Lauterbach's Bowerbird, is a medium-sized, approximately 27 cm long, bowerbird with a brownish-olive upperparts plumage, grayish-yellow upper breast, coppery crown, dark brown iris, yellow underparts, a black bill and...
, Chlamydera lauterbachi - Fawn-breasted BowerbirdFawn-breasted BowerbirdThe Fawn-breasted Bowerbird, Chlamydera cerviniventris is a medium-sized, up to 32 cm long, bowerbird with a greyish brown spotted white plumage, a black bill, dark brown iris, yellow mouth and an orange buff below. Both sexes are similar...
, Chlamydera cerviniventris
Note that the Gray Catbird
Gray Catbird
The Gray Catbird , also spelled Grey Catbird, is a medium-sized northern American perching bird of the mimid family. It is the only member of the "catbird" genus Dumetella...
(Dumetella carolinensis) and Black Catbird
Black Catbird
The Black Catbird is a songbird species in the monotypic genus Melanoptila of the family Mimidae. At 24 grams and 20 cm, it is the smallest mimid.It is found in Belize, Guatemala, Honduras, and Mexico...
(Melanoptila glabrirostris) from the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...
and the Abyssinian Catbird
Abyssinian Catbird
The Abyssinian Catbird is a species of bird in the Timaliidae family. It is monotypic within the genus Parophasma.It is endemic to Ethiopia. Its natural habitat is subtropical or tropical dry forests.-References:...
(Parophasma galinieri) from Africa are unrelated birds that belong to different families.
External links
- PBS Nature: Bower Bird Blues
- Bowerbird videos on the Internet Bird Collection