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Terms in this set (127)
1. forelimbs modified as wings
2. hindlimb adapted for walking, swimming, perching
All birds have
3. beaks ( made of keratin)
4. lay eggs
What era did birds first Mesozoic ( Cretaceous era)
appear?
birds were originally theropod dinosaurs
classified with
a group of theropods that includes Velociraptor, share
Dromeosaurs many additional derived characters with birds including
a furcula and lunate wrist bones
An intermediate fossil that shows both reptile and bird
Archaeopteryx characteristics. Discovered in 1861 and emerged during
the Jurassic period
Neornithes living birds
2 groups for neornithes Paleogna and Neognathe
ratites; large flightless birds, including ostriches and
Paleongna
emus
Flightless birds with small wings and flat breast bones
ratites
(flat sternum) - Ostrich, Emu, Rhea
birds other than the Paleognathae; have a keeled
Neognathae
sternum
- light weight
Bird feather characteristics - homologous to reptile scales
- contour feathers
large feathers that give shape to a bird's body and help
contour feathers
with flying
, Bird skeleton - pneumatized bones that are light but strong
characteristics - evolved from ancestors with diapsid skulls
pneumatic bones light, delicate bones laced with air cavities
Bird Digestive System crop, stomach ( proventriculus and gizzard), cloaca
Crop function (Bird stores food
digestive system)
Stomach function (Bird Proventriculus - secrete digestive juice
digestive system) Gizzard- muscular structure
Cloaca function ( Bird Common exit for digestion, reproduction and excretion
digestive system)
Adapted to flight with air sacs that help to efficiently
bird respiratory system
move more oxygen into the lungs
The sites of gas exchange in bird lungs. They allow air to
parabronchi flow past the respiratory surface in just one direction
and are continuous
Inspiration 1 - air enters the Posterior air sacs
Expiration 1 - air enters the lungs with parabronchi (gas
exchange)
Explain avian respiration
Inspiration 2 - air enters the anterior air sacs
Expiration 2 - air leaves anterior air sacs and goes to the
trachea
- testes are very small until breeding season and can
bird reproduction enlarge up to 300x
characteristics - Males of most species lack a penis
- Cloacal surfaces need to be in contact to mate
how many bird species 140
have gone extinct since
1861 due to human
influence
When did the dodo bird 1695
become extinct
was a bird that existed in North America until the late
Passenger Pigeon 1800s when it went extinct due to hunting and habitat
destruction.
list some bird species that passenger pigeon, great auk, dodo
have went extinct