This group includes birds that are morphologically and ecologically very diverse. At present, based on molecular data, the group comprises all the former Apodiformes (swifts, hummingbirds, starfrontlets, woodnymphs, nightjars) with the former Caprimulgiformes (goatsuckers, frogmouths, potoos, oilbirds) in the same group. The latter are nocturnal animals whose head morphology makes them easily distinguishable. They have a relatively large beak with a wide opening and large eyes that allow them to see clearly in the dark. Their plumage gives them excellent camouflage. Goatsuckers have typical bristles on their beaks. For a long time, myths surrounded the goatsucker  whose name derives from the fact that peasants once believed the nocturnal birds took advantage of nightfall to cling to goats’ teats and steal their milk.

The ancient Apodiformes (swifts, hummingbirds, starfrontlets, woodnymphs, nightjars) are birds with short legs that don’t allow them to walk, but only land or peck. These animals spend most of their lives in flight. Swifts can spend several days in a row without landing, the absolute record being held by the common swift Apus apus, which spends 10 months in a row in flight each year. Hummingbirds, on the other hand, are famous for their extremely fast, stationary flight, which is adapted to their largely nectarivorous diet. With their long, slender, curved beaks and long, thin, extendible tongues, they draw nectar from the bottom of the ruff of flowers they visit.