Aves Flashcards
Origins of birds
descended from a small group of dinosaurs (sauropsids) that remained after the extinction
What is Archeopteryx
fossil link between birds and reptiles
reptilian claws, tail and teeth but feathered wings
What is an Aitrieal chick like
Hatch naked and blind, depend entirely on their parents
What is a Precocial chick like
hatch with downy feathers, they can thermoregulate and feed themselves
What are the benefits of Arterial development
when the chick is ready to leave the nest it is fully mature and able to fend for itself
What are the benefits of precocial development
allows birds without nests to escape predators, common in water birds because they can swim to escape predators, which is cheaper than flying
outline the evolution of feathers in birds
started as reptilian scales, longer scales provided better insulation, but less flexibility so they split
Wings- where are the primaries and what do they do
1-9 from the middle to the tip of the wing
flight feathers
Wings- where are the secondaries and what do they do
1-9 from the middle to the body
flex to allow wing to fold
Wings- where are coverts and what do they do
at the ends of the feathers to protect them and provide a flat plane for flight
How does a bird preen
it rubs its beak on the preen gland that secretes oil that it rubs on its feathers to zip them up and move them into place
Wings- what is an alula
a small sub-wing at the front edge of the main wing that reduces turbulence
purpose of contour feathers
provide waterproofing and insulation
purpose of down feathers
fluffy feathers for insulation
purpose of semiplume feathers
hold contour feathers together
