To be fully functional as a bird, in addition to its feathers, Archaeopteryx needed a different type of lung, a differently structured heart, a different bone structure, stereoscopic vision, a constant body temperature and a redesigned egg.
(Archaeopteryx; needed; a different type of lung, a differently structured heart, a different bone structure, stereoscopic vision, a constant body temperature and a redesigned egg)
Archaeopteryx
needed
a different type of lung, a differently structured heart, a different bone structure, stereoscopic vision, a constant body temperature and a redesigned egg