Birds are survivors of the Cretaceous extinction 65 million years ago, which wiped out the planet's dinosaurs and left only some of their ancestors alive.

A new study based on genomic data suggests that between 10 and 15 million years after the dinosaurs died out, birds experienced a "super-species explosion" that led to the gradual evolution of more than 10,000 species of birds known as neornithines, which are responsible for 95 percent of all extant birds.

Bird is a general term for birds of prey, which are higher vertebrates adapted to life on land and in the air. Long feathers, can maintain a constant temperature of the body; thorax has a protruding keel protrusion, the whole body skeleton more empty space, filled with gas, so the body is lightweight; forelimbs into wings, hind limbs walking, most can fly, a wide range of activities.

Extended Information

Birds eat a variety of foods, including nectar, seeds, insects, fish, carrion, or other birds. Most birds are daytime active, while some are active at night or at dusk.

FlightMost birds fly; a few flat-breasted birds do not fly, especially those living on islands, which have largely lost the ability to fly as well.

When birds fly, they rarely get lost, even if the path is long. The reason is that they have their own "navigation system". During flight, they use many things to navigate for themselves, such as landmarks, the angle of the sun, the stars, smells, and even the geomagnetic field.

Baidu Encyclopedia - Bird (oviparous vertebrate with a feather-covered body)