What are birds?

Birds are vertebrates recognised by feathers, beaks and eggs; they are part of the surviving dinosaur lineage.

Flight and diversity

Many birds fly, but penguins and ostriches are among the flightless groups. Feathers serve insulation, display and protection as well as flight. Beak shapes vary with feeding; no single form fits all birds. Lightweight skeletons, strong muscles and effective respiration are significant adaptations in flying species. Nest protection, parental care and courtship vary across species.

Ecological roles and migration

Birds can eat insects, disperse seeds, scavenge or pollinate plants. Migratory species need resting sites between breeding and wintering areas. Changing bird numbers may offer clues about habitat, food and climate, though one observation cannot settle a trend. Conservation must consider sites used throughout a species’ life cycle.