Birds Flashcards
1
Q
What is a bird
A
Feathers Wings Warm blooded Beak (no teeth) Lays eggs, makes nests Hollow bones Unidirectional airflow in lungs
2
Q
Archaeopteryx
A
- toothed beak (reptilian character)
- wing claw (reptilian)
- airfoil wing with contour feathers (avian character)
- long tail with many vertebrae (reptilian)
3
Q
feathers older than birds
A
- feathers evolved before birds
- probs for display rather than flight
4
Q
bird-dinosaur link
A
- n.o. of digits?
- I-II-III like dinosaurs
5
Q
paedomorphy
A
adults retain juvenile features
6
Q
Modern bird skeleton
A
tail greatly reduced
vertebrae fused
teeth lost
hollow bones
7
Q
Lungs + air sacs
A
- Birds have relatively small lungs but also have air sacs
- Flow of air is unidirectional (more efficient as avoids mixing old and new air)
- inhalation: air sacs fill
- exhalation: air sacs empty; lungs fill
8
Q
How many repiratory cycles to move air through system?
A
2
9
Q
archosaurs
A
unidirectional airflow
10
Q
dinosaurs
A
hollow bones, air sacs, feathers
11
Q
birds
A
powered flight
12
Q
flight
A
- escape predators
- new food sources
- migrate when seasons change/environment deteriorates
13
Q
adaptations to flight
A
a) wing
b) bone structure
c) feather structure (shaft, barb, barbule, hook)
14
Q
wing shape
A
- high aspect ratio (broad and narrow)
- slow gliding, soaring e.g. albatross
15
Q
wing shape
A
- high aspect ratio (broad and narrow angled)
- high speed e.g. falcon
