Giant teratorn (Argentavis magnificens). This extinct species is believed to be the largest flying bird that ever lived. It lived from the late Miocene (6 million years ago) in Argentina. Fossil evidence suggests that it had a wingspan of up to 8 metres and a weight of up to 80 kilograms. The giant teratorn is closely related to the Andean condor and may have shared similar behaviour. It was probably too heavy for continuous flapping based flight and stationary take-off. It probably launched itself from a high perch or by ran downhill and gained height by soaring over rising thermal currents.