Physical characteristics

Bowerbird morphology and anatomy are broadly typical of oscinine passerines with the exception of a few traits. Typical songbirds have 9-10 secondaries (including tertials), but bowerbirds have 11-14. Bowerbirds also have an enlarged lachrymal (part of the skull cranium, near the orbit) that is paralleled only in the Australian lyrebirds (Menuridae). Bowerbirds have high average survivorship, and some individuals live for 20-30 years.

Within the family, great bowerbirds (Chlamydera nuchalis) are the largest and golden bowerbirds (Prionodura newtoniana) are the smallest. Males are typically, but not always, heavier and are larger in most body measurements than females. Juveniles and immature bowerbirds are generally smaller in wing length and weight than adults. The bill is typically stout and powerful; exceptions are the fine and longer bill of regent bowerbirds (Sericulus chrysocephalus) and the falcon-like toothed mandibles of tooth-billed bowerbirds (Scenopoeetes dentirostris). Legs and feet are stout, powerful, and scutellate.

The family exhibits 50-60 different plumages. Catbirds are sexually and cryptically monochromatic, and both sexes of the polygynous tooth-billed, Vogelkop (Amblyornis inor-natus), and Chlamydera bowerbirds are nearly identical. The other polygynous species are sexually dichromatic, with adult males adorned with colorful and ornate plumages and females

Maypole bowers: 1. Macgregor's bowerbird (Amblyornis macgregoriae)—bower decorated with spider's silk and leaves; 2. Streaked bowerbird (Am-blyornis subalaris)—bower decorated with flowers; 3. Archbold's bowerbird (Archboldia papuensis)—bower decorated with snail shells and orchids. Avenue bowers: 4. Flame bowerbird (Sericulus aureus); 5. Fawn-breasted bowerbird (Chlamydera cerviniventris)—elevated platform decorated with green fruit; 6. Yellow-breasted bowerbird (Chlamydera lauterbachi)—avenue bower with central passage, decorated with green fruit. (Illustration by Joseph E. Trumpey)

Bowerbird Maypole

Maypole bowers: 1. Macgregor's bowerbird (Amblyornis macgregoriae)—bower decorated with spider's silk and leaves; 2. Streaked bowerbird (Am-blyornis subalaris)—bower decorated with flowers; 3. Archbold's bowerbird (Archboldia papuensis)—bower decorated with snail shells and orchids. Avenue bowers: 4. Flame bowerbird (Sericulus aureus); 5. Fawn-breasted bowerbird (Chlamydera cerviniventris)—elevated platform decorated with green fruit; 6. Yellow-breasted bowerbird (Chlamydera lauterbachi)—avenue bower with central passage, decorated with green fruit. (Illustration by Joseph E. Trumpey)

being drab (some are barred ventrally). Juvenile and immature male plumages are similar to those of adult females. Males take five to seven years to fully acquire adult plumage.

Legs and feet are typically dark brown, olive-brown, olive, blue-gray, or black. Mouth color can be black, pale yellow, or orange-yellow depending on species. The skin of nestlings is pinkish, orange-pink, or pale flesh colored. Bill color is typically dark brown to black but can be pale or sexually dimorphic in some species. Iris color is typically pale to dark brown but is red in adult catbirds, whitish in Sericulus, and blue in Ptilonorhynchus.

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