Birdwings inhabit rainforests and adults are usually glimpsed along the forest periphery.
They feed upon—and are important long-range pollinators of—nectar-bearing flowers of the forest canopy, as well as terrestrial flowers, such as lantana.
They are strong flyers and seek sunlit spots in which to bask.

Breeding behaviour varies little between species; the female's role is relatively passive, slowly fluttering from perch to perch while the male performs an elaborate, quivering yet stationary dance 20–50 cm above her.

Birdwings are typified by large size (up to a maximum body length of 7.6 cm or 3 inches and a wingspan of 28 cm or 11 inches in O. alexandrae), showy colouration (in contrasting shades of green, yellow, black, white, and sometimes blue or orange), and slender, lanceolate forewings.
With few exceptions (i.e., the New Guinean O. meridionalis and O. paradisea), the hindwings lack tails.
Sexual dimorphism is strong in Ornithoptera species only, where males are black combined with bright iridescent green, blue, orange, or yellow while the larger and less colourful females are overall black or dark brownish with white, pale brown, or yellow markings.

Males and females of most Troides birdwings are similar and have jet black to brown dorsal forewings, often with the veins bordered in grey to creamy white.
At least one of these darkly-coloured species (T. rhadamantus) possesses thermoreceptors on the anal veins (A2 and A3) of the wings and on the antennal clubs.
The antennal receptors of the clubs—which also possess hygroreceptors that measure atmospheric humidity—are known as sensilla basiconica.
The thermoreceptors are sensitive to sudden increases in temperature; they are thought to help the butterfly thermoregulate and avoid overheating while basking.

The colours of most species are pigmentary (via papiliochrome); but two species, Troides magellanus and the much rarer T. prattorum, are noted for their use of limited-view iridescence: the yellow of the dorsal hindwings is modified by bright blue-green iridescence which is only seen when the butterfly is viewed at a narrow, oblique angle.
This "grazing iridescence" is brought about through diffraction of light (after back-reflection) by the wings' extremely steeply-set, multilayered rib-like scales (rather than the ridge-lamellae of most other iridescent butterflies, such as Morpho species).
Such limited-view iridescence was previously only known from one other species, the riodinid Ancyluris meliboeus.
In A. meliboeus, however, the iridescence is produced by ridge-lamellar scales and features a wider range of colours.

The close evolutionary relationship between Troides and Ornithoptera butterflies is well demonstrated by the fact that commercial breeders have produced numerous hybrids between the two.

The final and smallest genus is Trogonoptera with just two species.
They resemble each other, being overall black with iridescent green markings and a red head.
Females are duller than males.
Birdwings inhabit rainforests and adults are usually glimpsed along the forest periphery. They feed upon—and are important long-range pollinators of—nectar-bearing flowers of the forest canopy, as well as terrestrial flowers, such as lantana. They are strong flyers and seek sunlit spots in which to bask.
Breeding behaviour varies little between species; the female's role is relatively passive, slowly fluttering from perch to perch while the male performs an elaborate, quivering yet stationary dance 20–50 cm above her.
Birdwings are typified by large size (up to a maximum body length of 7.6 cm or 3 inches and a wingspan of 28 cm or 11 inches in O. alexandrae), showy colouration (in contrasting shades of green, yellow, black, white, and sometimes blue or orange), and slender, lanceolate forewings. With few exceptions (i.e., the New Guinean O. meridionalis and O. paradisea), the hindwings lack tails. Sexual dimorphism is strong in Ornithoptera species only, where males are black combined with bright iridescent green, blue, orange, or yellow while the larger and less colourful females are overall black or dark brownish with white, pale brown, or yellow markings.
Males and females of most Troides birdwings are similar and have jet black to brown dorsal forewings, often with the veins bordered in grey to creamy white. At least one of these darkly-coloured species (T. rhadamantus) possesses thermoreceptors on the anal veins (A2 and A3) of the wings and on the antennal clubs. The antennal receptors of the clubs—which also possess hygroreceptors that measure atmospheric humidity—are known as sensilla basiconica. The thermoreceptors are sensitive to sudden increases in temperature; they are thought to help the butterfly thermoregulate and avoid overheating while basking.
The colours of most species are pigmentary (via papiliochrome); but two species, Troides magellanus and the much rarer T. prattorum, are noted for their use of limited-view iridescence: the yellow of the dorsal hindwings is modified by bright blue-green iridescence which is only seen when the butterfly is viewed at a narrow, oblique angle. This "grazing iridescence" is brought about through diffraction of light (after back-reflection) by the wings' extremely steeply-set, multilayered rib-like scales (rather than the ridge-lamellae of most other iridescent butterflies, such as Morpho species). Such limited-view iridescence was previously only known from one other species, the riodinid Ancyluris meliboeus. In A. meliboeus, however, the iridescence is produced by ridge-lamellar scales and features a wider range of colours.
The close evolutionary relationship between Troides and Ornithoptera butterflies is well demonstrated by the fact that commercial breeders have produced numerous hybrids between the two.
The final and smallest genus is Trogonoptera with just two species. They resemble each other, being overall black with iridescent green markings and a red head. Females are duller than males.
Birdwing