Lecture 4 Flashcards
What kind of flying does long narrow wings allow?
Gliding
What kind of flying does short round wings allow?
Getting up fast
What kind of flying does sharp wings allow?
Fast flight
What kind of flying does elongated round wings allow for?
Lift and gliding
What are the four forces acting on bird wings in flight
Drag, Gravity, lift and thrust
What muscle controls the downstroke
pectoralis muscle
What muscle produces the upstroke
supracoracoideus
What is the the air pressure below and above the wing? Why?
The air below is high, above is low. athe curvature of the wint causes a change in air pressure (thick to thin)
What allows birds to hover and why?
The alula, allows a steeper angle of attack without reduction of lift from turbulence
How does having 2 coloured wings generate lift (black on top)
The temperature differences causes lift, lower air pressure above, lowering drag and increasing lift
How do birds use thermals to fly
Go up in thermals (warm air) and then drop to cover long distances
Why do birds use V formation to fly
Saves 50% energy, the bird in front uses the most and the rest have less pressure
How do birds expel heat
Their breath
Describe the respiration process of birds
Breathes in, posterior air sac fills, little goes into lung, breathes out, the posterior air sacs compress forcint air into the lungs, breath in, anterior air sacs expand as air leaves lungs, exhales the air out
What are some ways that birds reduce weight for flying
no teeth, pneumatic bones, lightweight coat, waterproof coats, single ovary, seasonal gonads, lean body
why do some birds not fly?
if their ecology changes so that it doesnt need to fly then they reduce wings
What are the two diving strategies emperor penguins use
- cut off blood supply to muscles (prioritize brain and heart)
- direct blood to muscles
Why do penguins have high hemoglobin levels
increased oxygen stored in muscles
How do penguins prevent the bends
They adjust the angle of ascent
How to penguins reduce drag as they ascend
they surface and collect air under plumage, they dive and the pressure increase traps the air, when they ascend the bubbles are released which decreases drag and allows them to accelerate out of the water
What are features of hummingbird feeding
feed on nectar, have enzyme sucrase to digest it, straw like tongue
How do hummingbirds fly?
Hover, figure 8 pattern
What allows the albatross the hold its wings out for a long time
patagial tendon
How do albatross’s fly? why do they travel so far
Their nostrils measure speed of wind, they ride the wind up and down to go far without flapping wings. They go far because food sources are not predictable and patchy
