Bird Physiology
How does the flexor tendons help birds?
It locks the toes in a grasping position, reducing energy expenditure.
What was Archeopteryx?
Feathered dinosaur that was the ancestor to modern birds.
What are feathers made of?
Beta-keratin
Does blue pigment exist?
The two main muscles for flight
Pectoralis muscle- downward stroke
Supracoracoideus muscle- pulls wing back down
Why are birds hot?
Higher body temp= faster physiologial rates, allowing for higher endurance for flight.
Theropods.
What are the main feather types for flying?
Rectrices and remiges.
Two classes of pigments and their colorations and how they are obtained.
Melanins: brown and reddish brown (produced by bird)
Carotenoids: Orange and yellows (diet)
What does the alula do?
First feathered digit on hand, controls airflow over the wing to maintain lift and prevent stalling
Difference between red and white muscle fibers
White muscle provides short term power (anaerobic). Think chickens, white meat, short flights.
Red muscle provides sustained flight (aerobic). Think buffleheads, red meat, migrating.
Did feathers evolve from the evolution of flight?
Name three feather tracts on the wing
Primaries, secondaries, coverts (GML), terts
What are the two different plumage types and what seasons are they in?
Alternate (breeding) and basic (nonbreeding)
How is lift produced?
Faster air moving over the top of the wing.
Bones in the pectoral girdle
- Scapula
- Furcula
- Coracoids
Commonalities between birds and reptiles
- Occipital condyle
- Egg production
- Lower mandible > 3 bones
- Single ear bone
5 main sections of a contour feather
Vane
Rachis
Calamus- anchor
Plumulaceous- lower
Pennaceous- upper
What are the two states birds can be born into?
Altricial (blind)
Precocial (feathered)
Three main forces acting on flight
- Weight
- Drag
- Lift
Adaptations for going above thermoneutral zone
- Panting
- Shading
- Bathing/diving
- Flying in cold air
Traits supporting theropod origins
- Feathers
- Carpometacarpus
- Furcula
- Pubic bone
- Semilunate carpal
Name the different types of feathers and their uses
Rectrices and remiges- flight
Contour- color
Down- insulation
Semiplume- insulation
Filoplume- info on positions of other feathers
Bristles- whiskers
Powderdown- barbs disintegrate
Two molt cycles that all birds experience
Prejuvenile & Prebasic
Four different wing shapes
Long and wide- soaring
Narrow and pointed- fast flying
Long and narrow- gliding birds
Short and rounded- quick, powerful bursts