What characteristics do all birds have in

common?

All birds…

Are vertebrates

Are endothermic

Have feathers

Have a four-chambered heart

Lay eggs

The bodies of most (but not all) birds are

adapted for flight

In order to fly birds need…

1) Hollow bonesto make the bird lightweight

In order to fly, birds need…

2) large chest muscles to move their wings

In order to fly, birds need…

3) Feathers ---they are the only animals to have feathers

Different kinds of feathers:

Contour Feather: one of the large feathers on a bird that gives shape to a bird’s body

Flight Feathers: long contour feathers that extend beyond the body on the wings and tail

Help the bird to balance and steer

Contour feathers in general have a central shaft and projections called barbs

Down Feathers: short, fluffy feathers that are specialized to trap heat and keep the bird warm

Found right next to the bird’s skin at the base of the contour feathers

Are soft and flexible

Feathers

Contour Feathers

Down Feathers

Feathers

Obtaining Food

Birds must obtain a lot of food to provide the

energy needed for flight

Because they need energy for flight and

they are endotherms, birds need a lot of food.

Each day, the average bird eats food equal to about a quarter of its body weight

This is why the phrase “You’re eating like a bird” is incorrect….bird eat a lot!

What do birds use to capture, grip and

handle food?

Bills – shaped to help birds feed quickly and

efficiently A bird’s bill is shaped depending on what it eats

Example: The pointy, curved bill of a hawk

acts like a meat hook to pull off bits of its prey

Example: A duck’s bill acts like a kitchen strainer,

separating out seeds and tiny animals from muddy

pond water

Example: Pelicans need a large bill to scoop fish out of the water

Birds have special organs to digest food

2 organs that birds have that humans do

not are a gizzard and a crop

Crop: an internal storage tank for storing food inside the body after swallowing it

A muscular pouch near the throat

Gizzard

Gizzard: a thick-walled, muscular part of the stomach that squeezes and grinds partially digested food

Birds have one to make up for the fact that they do not have teeth!

The gizzard does the same grinding function for birds that your teeth do for you

Keeping conditions stable

Being endotherms, birds need to keep warm

To maintain their body temperature, they use energy from food and feathers to trap heat

Down feathers are specialized to trap heat, as they are found right next to a bird’s skin

Birds Reproduction

Have internal fertilization

Lay amniotic eggs

In most species, a female lays eggs in a nest

Bird eggs will only develop at a temperature close to the body temperature of the parent bird

A parent bird usually incubates the eggs by sitting on them to keep them warm

Parents take care of their babies until they learn how to fly