Teratornithidae

Teratornithidae is an extinct family of large birds known from North and South America, spanning the Miocene to the Pleistocene and related to storks and condors.

Teratorn: Teratorn is a genus of extinct teratornithid birds from the Pleistocene of North America. Its fossils provide a concrete example of the family’s giant-bodied members.
Argentavis magnificens: Argentavis magnificens is an extinct giant bird from the Miocene of Argentina. It is among the largest known teratornithids and illustrates the family's South American record.
Soaring flight: Soaring flight is sustained flight that uses rising air currents to reduce flapping. Large teratornithids could exploit air currents to remain aloft efficiently.
Miocene: The Miocene is a geological epoch lasting from about 23 million to 5.3 million years ago. The family's South American fossil record extends back to this epoch.
Avian phylogeny: Avian phylogeny is the pattern of evolutionary relationships among bird lineages. Teratornithid placement has shifted as anatomical evidence and classification have changed.
Aves: Aves is the biological class comprising all living birds and their extinct descendants. Teratornithids belong within the broader evolutionary group of birds.
Aiolornis incredibilis: Aiolornis incredibilis is an extinct teratornithid known from Pleistocene deposits in western North America. Its remains represent a large North American member of the family.
Bird flight: Bird flight is locomotion through the air using wings and aerodynamic forces. Teratornithid size and wing proportions are interpreted through the mechanics of bird flight.
Pleistocene: The Pleistocene is an epoch lasting from about 2.58 million to 11,700 years ago. Many familiar North American teratornithid fossils come from this epoch.
Convergent evolution: Convergent evolution is the independent evolution of similar traits in separate lineages. Similarities to condors may not by themselves establish close ancestry.

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