<P> California condors' wingspan measures up to 2.9 m (9.5 ft), and they can weigh up to 10.4 kg (23 lb). The skin on the necks will vary in color, depending on the age of the birds . Adult birds' skin color can range from cream, pink, yellow, or even orange during breeding season . </P> <P> Fossils from the Pleistocene era have been found in various parts of North America, including New York and Florida, leading scientists to believe that California condors or their ancestors once lived on the west coast of North America as well as all the way to the eastern coast . Some scientists also believe that an ancient relative of the condor, Argentavis magnificens from South America, may have been the largest flying bird ever with a wingspan of 7 metres (23 ft). </P> <P> Sexual maturity and breeding behavior do not appear in the condor until 5 or 6 years of age . They may live for 50 years or more, and mate for life . The world's oldest condor died at 100 in the Jardin d'Essai du Hamma in Algiers . </P> <P> The young are covered with a grayish down until they are almost as large as their parents . They are able to fly after six months, but continue to roost and hunt with their parents until age two, when they are displaced by a new clutch . There is a well - developed social structure within large groups of condors, with competition to determine a' pecking order' by body language, competitive play behavior, and a wide variety of vocalizations, even though the condor has no voice box . </P>

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