Birds

Australian National Botanic Gardens, Canberra

Bowerbirds /ˈbaʊərbɜːrd/ make up the bird family Ptilonorhynchidae. They are renowned 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. The Ailuroedus catbirds are monogamous, with males raising chicks with their partner, but all other bowerbirds are polygynous, with the female building the nest and raising the young alone. These latter species are commonly 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 courtship the male bowerbird will dance to the female in an attempt to attract her. Bowerbirds as a group have the longest life expectancy of any passerine family with significant banding studies. The two most studied species, the green catbird and satin bowerbird, have life expectancies of around eight to ten years and one satin bowerbird has been known to live for twenty-six years. For comparison, the common raven, the heaviest passerine species with significant banding records, has not been known to live longer than 21 years. The most notable characteristic of bowerbirds is their extraordinarily complex courtship and mating behaviour, where males build a bower to attract mates. 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. Inspired by their seemingly extreme courtship rituals, Charles Darwin discussed both bowerbirds and birds-of-paradise in his writings. 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. Bowerbirds have also been observed creating optical illusions in their bowers to appeal to mates. They arrange objects in the bower's court area from smallest to largest, creating a forced perspective which holds the attention of the female for longer. Males with objects arranged in a way that have a strong optical illusion are likely to have higher mating success. - https://en.wikipedia.org/wiki/Bowerbird