Are there any birds that could theoretically carry a human on top of them?
A picture of men racing on ostriches in okhlahoma. Largest known flying bird ever: Argentavis - Wikipedia had a wingspread estimated at 6 to 7+ meters (19 to 20+ feet); with some estimates closer to 24 feet. They lived in and around the southern Andes during the late Miocene to early Pliocene and weighed approximately 70 to 72 kg (154 to 159 lb). Although this bird had a larger wingspan its wings had a higher aspect ratio (they were narrower for their length) and was only half the overall body mass: Pelagornis sandersi - Wikipedia http://www.sci-news.com/paleontology/science-pelagornis-sandersi-largest-ever-flying-bird-02046.html For comparison here is a close relative along with some other contenders including the Ailornis of N. America a likely match for the legendary Thunderbird: Pterosaurs got considerably larger but they weren’t birds. Argentavis had a wing loading of 1.77 lbs./ sq. ft. (c. 11.5 kg/m²) and lifting a 170 lb. human mal...
