Things to be familiar with Flashcards
definition of a bird
all feathered animals
anatomical differences between prehistoric birds and the birds of today
not all feathered animals were birds back then and they had teeth, longer tails, heavier beaks, no sternum bones
archaeopteryx
the first and most famous fossil of an animal with feathers, found in Bavaria in 1861. Clearly a toothed reptile - but it had well developed flight feathers on the forelimbs and a long tail
Theropod dinosaurs and characteristics that they shared with birds both physically and behaviorally
characterized by being bipedal and most were carnivorous. Like T-Rex. Many had feathers, laid eggs in nests, had wish bones, hollow bones, four chambered heart, small theropods evolved into birds
reasons for the lack of bird fossils
good for aquatic, silt preserves it
number of bird species, overall population trends and the number of birds considered to be threatened with extinction
- the overall bird population has decline 20-25%
- total number: 10,052
- one in eight are threatened with extinction
basis for the classification (taxonomy) of birds in to orders
- based on similarity of structure
- animals and plants also classified this way
- biochemical classification is based on blood proteins, egg proteins, DNA analysis
convergent evolution
unrelated species may come to be structurally similar if they evolve in similar environments
the evolutionary advantage for the development of feathers
camo, warmth, social signaling
advantages and disadvantages of flight, and the evolution of flightless birds
- can escape predators
- but requires a lot of energy
- flightless birds can save energy and can be larger (most in Hawaii and New Zealand)
anatomical and physiological adaptations for flight
- skeleton weighs less
- no urinary bladder
- most weight is in center for gravity
typical arrangement of toes in birds as well as less common arrangement of toes in birds
- Most perching birds have anisodactyl feet, with three toes pointing forward and one rear pointing toe
- Woodpeckers, parrots, cuckoos, and owls have zygodactyl feet, with the two outside toes pointed backward and the middle toes pointing forward
- In a pamprodactyl arrangement, all the toes point forward, and this has been reported to be found in mousebirds and some swifts.
- In the syndactyl foot, the arrangement of toes is the same as in anisodactyl, but with two toes fused from the base partway up their length. Th is arrangement is found in Coraciiformes (kingfi shers and allies). Ratites are tridactyl (three toes), except for Ostriches, which are didactyl
methods birds use to get into the air
- big birds use high cliffs and just jump off
- small birds get running start
concept of lift and anatomical structure of the wings that create lift
- front wing is thicker than back of wing
- back curves downward so air trapped by downward feathers to lift bird up
- pectoralis major pulls wing down
- pectoralis minor lifts wing up
types of feathers
- down feathers are not aerodynamic
- filoplumes are for sensory perception
- bristles are around the face and used for sensory perception
- retrices are large tail feathers, symmetrical, balance
- remiges are primary and secondary flight feathers
- contour is major body covering feather
