Bower bird latest pictures
 Bowerbirds  and catbirds make up the bird family Ptilonorhynchidae. The family has  20 species in eight genera. 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.  catbirds are monogamous and raise chicks with their mate, but all other  bowerbirds are polygymous, 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.
Bowerbirds  and catbirds make up the bird family Ptilonorhynchidae. The family has  20 species in eight genera. 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.  catbirds are monogamous and raise chicks with their mate, but all other  bowerbirds are polygymous, 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. 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. This hypothesis is  not well supported because species with vastly different bower types  have similar plumage. Borgia has suggested[citation needed] 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.[citation needed] Coleman and  colleagues[who?] 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.
  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. This hypothesis is  not well supported because species with vastly different bower types  have similar plumage. Borgia has suggested[citation needed] 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.[citation needed] Coleman and  colleagues[who?] 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. Bower bird
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Bower bird
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.




 
 

 
 
 
 
 
 
 
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