The Eastern Bluebird, Sialia sialis, is a small thrush found in open woodlands, farmlands and orchards,
and most recently can be spotted in suburban areas. It is the state bird of Missouri and New York.

Modern birds are characterised by feathers, a beak with no teeth, the laying of hard-shelled
eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton.

Many species undertake long distance annual migrations, and many more perform shorter irregular movements.
Birds are social; they communicate using visual signals and through calls and songs, and participate
in social behaviours, including cooperative breeding and hunting, flocking, and mobbing of predators.

Many species are of economic importance, mostly as sources of food acquired through hunting or farming.
Some species, particularly songbirds and parrots, are popular as pets.