When sea levels were lower during the ice ages, these islands were joined to the Australia-New Guinea continent, which allowed terrestrial plants and animals to move between them.

Common canopy trees include Pometia pinnata, Octomeles sumatrana, Alstonia scholaris, and species of Ficus and Terminalia.

Other tree genera include Pterocarpus, Artocarpus, Planchonella, Canarium, Elaeocarpus, Cryptocarya, Celtis, Dracontomelon, Dysoxylum, Syzygium, Vitex, Spondias, and Intsia.

Dominant canopy trees include species of Pometia, Canarium, Anisoptera, Cryptocarya, Terminalia, Syzygium, Ficus, Celtis, Dysoxylum, and Buchanania.

[1] On Waigeo Island and the adjacent northwest coast of New Guinea, ultramafic rocks result in a serpentine flora, a belt of low shrubby vegetation composed of Alphitonia, Dillenia alata, Myrtella beccarii, and Styphelia abnormis.

Native mammals include the Arfak long-beaked echidna (Zaglossus bruijni), dusky pademelon (Thylogale bruinji), New Guinea quoll (Dasyurus albopunctatus), red-bellied dasyure (Phascolosorex doriae), ursine tree-kangaroo (Dendrolagus ursinus), brown forest wallaby (Dorcopsis muelleri), Lorentz's mosaic-tailed rat (Melomys lorentzii), Shaw Mayer's brush mouse (Pogonomelomys mayeri) and lowland brush mouse (Pogonomelomys bruijni).