Birds Flashcards
Give 4 diagnostic characteristics of birds
- Feathers
- Beak with no teeth
- Pneumatised bones
- Unique respiratory system
4 functions of flight
Escape predators
Foraging
Migration
Sexual displays
3 adaptations to facilitate flight
Feathers and wings
Specialised lungs and air sacs
Enlarged sternum to act as an anchor for flight muscles
4 weight saving modifications for flight
Lack of urinary bladder
One ovary
Pneumatised bones
Toothless beak
What are feathers and what is found in them aswell as in reptiles
Modified scales - B-keratin
What are on the barbules in feathers
Hooks
What gland secretes oil for preening
Uropygial
Difference in the contour and the downey feather
Contour - Stiff from presence of hooks and contributes to the aerodynamics of flight
Downey - Free form with no hooks and provides insulation
What is the aspect ratio
Wing breadth : Wing length
What is an airfoil wing and which part of the wing creates that - Primary, Secondary or Coverts
A body that is capable of producing more lift than drag
Why do the lungs not expand in birds
No diaphragm
Outline the respiratory mechanism
Inhalation brings air into airsacs - upon exhalation air is forced out through the lungs and oxygen is exchanged
What are beaks made out of
Give 2 shape examples and species to match
Keratin
Hooked - eagles
Conical - Hawfinch
Define digitigrade
Walking on their toes rather than the whole foot
If a bird was 3 toed how would you describe them
Tridactyl
Before the egg laying in reproduction there is territorial defence, courtship and nest building - how do black grouse courtship
Lekking which is the aggregation of males to engage in competitive displays
Purpose of incubation and an adapted feature than female birds have
Regulate egg temperature
Brood patch for skin-skin contact
Once the egg has hatched and the period of parental care is over the chicks fledge, disperse and possibly migrate - what triggers migration
Phenological/Seasonal changes
What is the purpose of migrations
To optimise availability of food sources and breeding habitat
How do birds navigate once migration has begun
Celestial queues
Which sub-order is the last ancestor for birds
Therapods
Shared reptile-avian feature
What is the occipital condyle - how many do birds and mammals have
The point at which the skull attaches to the vertebral column
Birds have 1 and humans have 2
Shared reptile-avian feature
How many ear bones do mammals and birds have
Birds have 1
Mammals have 3
Shared reptile-avian feature
Jaw
Birds lower jaw is composed of 5 bones whereas mammals only have 1
Shared reptile-avian feature
RBC
Birds have nucleated RBCs
Shared reptile-avian feature
Egg (2)
Bird eggs are more calcified
Presence of an egg tooth
Shared reptile-avian feature
What membrane moves horizontally across the eye and what are 2 functions of it
Nictitating membrane
Clear debris and Maintain moisture
