An air-filled sac within birds’ lungs is believed to modify mechanics of flight while soaring

Soaring birds—like osprey, eagles, falcons, even vultures—can stay aloft in the air seemingly forever, rarely flapping their wings. They glide along rising air currents in a way that has fascinated humans and scientists for centuries. Soaring birds—like osprey, eagles, falcons, even vultures—can stay aloft in the air seemingly forever, rarely flapping their wings. They glide along rising air currents in a way that has fascinated humans and scientists for centuries. Plants & Animals Evolution Phys.org – latest science and technology news stories