Flight Flashcards
Name a species which has secondarily lost its ability to fly.
Kiwi
Why does the loss of flight usually occur ?
Inhabit islands with greatly reduced mammalian predation.
Why is it energetically costly for a bird to fly ?
Commit huge amounts of the body (pectoral muscle)
Energetically expensive process
What do kiwis invest their energy in ?
considering they do not fly
Egg production, Kiwi egg is 30% of body size,
Give the key adaptions of the feather fro flight,
Light, Strong, Streamlined, Flexible
How have birds achieved lightening of the skeleton ?
Reduced no. of bones Hollow bones (no bone marrow)
How have birds adapted their skulls for flight ?
Lost heavy jaw structure
Lack muscle and bones
Why are birds toothless ?
A gizzard is a lighter solution to molars.
Why is it beneficial for birds to oviparous ?
All maternal care takes place outside the body, reducing the weight of the mother.
In season, what happens to a female birds one ovary ?
It will enlarge drastically.
Reducing impact of weight outside breeding season.
How has a birds skeleton been strengthened ?
Fusion of 2 collar bones to form a wishbone.
Enlargement of the keel
The larger the keel….
The more powerful the flight
What is the function of the Pectoralis ?
Muscle which enables the downward stroke of the wings,
Which muscle is larger, Pectoralis or Supracoracoideus ?
Pectoralis muscle, can be up to 35% of body weight
What is the function of the Supracoracoideus ?
Returns wings to upstroke
How many other wing muscles do birds have and what is there function ?
48
For Adjustments, landing and take off.
What is the primary sense organ of birds ?
Sight
Describe the sensory adaptions of birds.
Large eyes
Large brains
Ample processing centres.
What structures make up the wing of a bird ?
Forelimb, bones have fused in fingers and hands to make wing.
Powerful tendon
Compact tiny muscles
What is the disadvantage of wings ?
Decreased flexibility, In comp. hands and paws.
Describe the air foil shape of the wing.
Leading edge is rounded
Tapers to a thin point at the trailing edge.
What are the 4 competing forces acting on a bird ?
Weight, Drag
Thrust, Lift
Describe what happens on the upper side of the wing to generate lift
Air speed increases over the curved wing relative to the slower lower surface
^ speed means reduced pressure at top of wing, lifting the bird upwards.
What does Bernoulli’s principle state ?
That a fast speed of air flow can decrease pressure