Birds
birds
The feather is
the defining characteristic of birds.
There are about 10 thousand different species of bird. There is great variety in where these animals live, what they eat and how they look and behave.
Some birds, such
as Goldfinches, like to eat seeds. Others, such
as the Kingfisher and Heron
catch fish. Other water birds, such as Swans
prefer water weed. Many birds, including Blue
Tits, love insects. Others such as Owls and
Kestrels hunt for small mammals such
as voles and mice.
Most birds can
fly. Light weight and high energy are therefore important. Food eaten
is usually quickly digested, and has high energy value.
There is little
accumulation of fat, and the young develop outside the parent's body,
in eggs. This helps to keep the bird light, aiding flight.
Life in the air
demands a powerful propellant and for this they have high temperatures,
rapid heartbeats and high performance muscles.
birds