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CENTER for BIOLOGICAL DIVERSITY Because life is good

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Birds are bipedal, warm-blooded, egg-laying vertebrates with about 10,000 living species. The fossil record indicates birds evolved from theropod dinosaurs 200 to 150 million years ago, and the earliest known bird is the late Jurassic Archaeopteryx. There is significant evidence that birds evolved from theropod dinosaurs; as more non-avian theropods that are closely related to birds are discovered, the formerly clear distinction between non-birds and birds becomes blurred. A genetically consistent evolutionary tree would classify birds as reptiles, though some scientists would elevate birds, turtles and crocodilians to their own class, on an equal footing with reptiles.

Globally, 1,373 species of birds, or about 13 percent of the total of 10,425 extant described bird species, were deemed endangered or threatened with extinction by the International Union for Conservation of Nature’s Red List. In the United States, 77 bird species are at risk of extinction.

Andean flamingo
Ashy storm petrel
Bald eagle
Bicknell's thrush
Black-backed woodpecker
Black-breasted puffleg
Blue-billed curassow
Brown-banded antpitta
Cactus ferruginous pygmy owl
California condor
California spotted owl
Cape Sable seaside sparrow
Cauca guan
Chatham petrel
Chilean woodstar
Coastal California gnatcatcher
Desert nesting bald eagle
Eastern brown pelican
Esmeraldas woodstar
Fiji petrel
Galápagos petrel
Gorgeted wood-quail
Hawaiian petrel
Heinroth's shearwater
Inyo California towhee
Kittlitz's murrelet
Least Bell's vireo
MacGillivray's seaside sparrow
Magenta petrel
Marbled murrelet
Medium tree finch
Mexican spotted owl
Mono Basin sage grouse
Newell's shearwater
Northern goshawk
Northern spotted owl
Okinawa woodpecker
Passenger pigeon
Piping plover
Queen Charlotte goshawk
Rota bridled white-eye
Southwestern willow flycatcher
Spectacled eider
St. Lucia forest thrush
Steller's eider
Tinian monarch
Tricolored blackbird
Western burrowing owl
Western gull-billed tern
Western snowy plover
White-tailed ptarmigan
Xantus's murrelet
Yellow-billed cuckoo
Yellow-billed loon

Photo by Scott Frier, USFWS