Bird Anatomy Flashcards
What is the difference in bone composition between mammals and birds
Birds have higher composition of calcium phosphate
What is pneumatised bone?
A pneumatized bone is hollow or contains many air cells,
What are some examples of pneumatised bones in birds?
Humerus
Thoracic girdle
Certain ribs
What is the jaw of a bird like?
The articulation of the upper jaw and cranium is an elastic zone
the upper jaw of a bird attaches to the skull at a flexible hinge. When a bird opens its mouth, the lower jaw moves downward and the upper jaw moves upward relative to the skull. Birds can therefore open their mouths wider than a mammal. —> prokinesis
What is the the os quadrum?
An extra bone that allows for extra wide opening of the jaw
What is the ocular size of birds like?
Very small bone in between eye sockets, as birds have large eyes
What is the cranial bone like/
Spongy due to pneumatic bones
Small cranial cavity
What is the occipital bone like In birds?
Single occipital condyle
Allows wider range of head movement
What is the cervical vertebrae like?
Can have ribs articulating them
Very uniform in shape, so difficult to distinguish between cervical and thoracic end
Large number of vertebrae to allow for flexible neck
What is the thoracic vertebrae like?
Ribs attached that articulate with the sternum
3-10 thoracic vertebrae
What is the notarium?
First 4 vertebrae are fused
What are feathers made from,
Keratin
What is the calamus
The smooth, unpigmented base, which extends under the skin into the feather follicle,
What is the rachis or scarpus
Theportionabovetheskin,fromwhichthe smaller barbs or branches extend,
What are contour feathers
Cover surface of most of the bird
They protect the bird from sun, wind, rain, and injury. Often, these feathers are brightly colored and have different color patterns. Contour feathers are divided into flight feathers and those that cover the body.
Flight feathers: Flight feathers are the large feathers of the wing and tail. Flight feath
What are flight feathers
Large feathers of the wing and tail
Collectively known as the remiges
What are primary feathers like?
Attaches to metacarpal and phalanges
Responsible for forward thrust
Usually 10 feathers
What are the secondary feathers like?
Attach to the ulna
Helps with lift
Usually 10-14
What do the tail feathers help with
as brakes and a rudder, controlling the orientation of the flight.
What are down feathers used for
Small feathers under contour feathers
Traps air in insulating layer by skin, protecting from heat and cold
What is a blood feather
New developing feather
Artery and vein that extends through the shaft
Has dark appearance
What colour is a mature feather
White
What colour feathers contain melanin
Brown to black
What colour are feathers contain carotenoids?
Yellow, orange, red
What colour feathers contain porphyrin
Red and green
How is the humerus adapted for flight
Short and thick to support flight muscles
How are the radius and ulnar adapted for flight
the ulna has small tubercles to which the muscles controlling the position of the secondary flight feathers are attached
How are the carpals and metacarpals adapted for flight
The carpals and metacarpals are fused, and there are only three digits. This structure keeps the primary flight feathers in the right positions during flapping flight
What is the carpus like in birds
Has a crescent shaped carpal bone
Allowes abduction
Allows wing to fold at rest
What two muscles are used for flight
Pectoral
Supercoracoideous
How are the pectoral muscles used in flight
adduct shoulder joint to create powerful downstroke.
Larger than supracoracoideous
How does supracoracoideous muscle assist in flight
lies deep to the pectorals, but its tendon runs over the top of the shoulder joint through the foramen triosseum to insert on top of the humerus. Abducts shoulder joint to create upstroke.
