Birds have feathers, wings, lay eggs and are warm blooded.^

There are around 10000 different species of birds worldwide.^

The Ostrich is the largest bird in the world.^

Scientists believe that birds evolved from theropod dinosaurs.^

Birds have hollow bones which help them fly.^

The Sword-billed Hummingbird is the only bird with a bill longer than its body.^

There are over 9,500 species of birds in the world. Scientists typically group them into 30 categories. Birds are the most widespread of all animals around the world.^

Approximately 2/3 of all the bird species are found in tropical rain forests.^

Hoatzin chicks have two claws on each wing. When they climb out of the nest, they use their claws to hold on to mangrove trees. They lose their claws once they mature, but they remain poor flyers.^

The longest feathers ever seen were on a chicken in Japan. Its tail feathers measured 34.7 feet (10.59 m) long.^

To make them more lightweight, most birds do not have bladders to store urine. Rather than producing liquid urine to get rid of wastes, they produce a white, pasty substance. However, while an ostrich does not have a bladder like a mammalian bladder, it is unique among birds because it does have a complete separation of feces and urine.^

A bird’s lungs are much more complicated and efficient and take up more space than those of mammals, such as humans. A human’s lungs compose about 1/20 of its body, but a bird’s takes up 1/5.^

The Australian pelican has the longest bill of any bird in the world. It is nearly 2 feet (0.5 m) in length. The sword-billed hummingbird, with its 3.9-inch (10 cm) bill, is the only bird with a bill that’s longer than its body.^

Owls cannot swivel their eyes. Instead they move their heads completely around to see straight behind them. They live on every continent except Antarctica. Soft fringes on their wings make their flight essentially silent.^

Famous birds include Ba in Egyptian mythology, Bar Juchne in the Talmud, The Cu Bird in Mexican folklore, the Firebird in Native American mythologies, Harpies in Greek mythology, the Phoenix in Egyptian mythology, Quetzalcoatl in Aztec mythology, and the Raven in Native American religions.^

Famous birds in literature include the Albatross in The Rime of the Ancient Mariner, Archimedes in The Once and Future King, Chicken Little, Chanticleer in Chaucer’s Nun’s Priest’s Tale, Fawkes and Hedwig in Harry Potter, Mother Goose, the Raven in Edgar Allen Poe’s “The Raven,” Owl in Winnie the Pooh, Thorondor (the king of eagles) in J.R.R. Tolkien’s Lord of the Rings, and The Ugly Duckling.^