Birds

Question 1

what is their unique feature

Answer 1

feathers

Question 2

bird characteristics

Answer 2

• General uniformity of structure compared to other taxa • Flight restricts morphological diversity
• Feathers
• Forelimbs modified into wings
• not always used for flight
• Hindlimbs adapted for walking, swimming, or perching
• Keratinized beaks and feathers
• oviparous

Question 3

Paleognathae

Answer 3

• Large flightless birds
• Ostrich, kiwi
• Flat sternum with poorly developed pectoral muscles

Question 4

Neognathae

Answer 4

• All other birds
• Nearly all fly
• Penguins are flightless (although they use their wings to ‘fly’
underwater)
• Keeled sternum with powerful flight muscles

Question 5

what are the adaptations for flight?

Answer 5

• Wings for lift and propulsion
• Bones light yet rigid
• Respiratory system highly efficient
• intense metabolic demands
• Rapid and efficient digestive system
• Energy-rich diet
• High-pressure circulatory system

Question 6

feather structure (4 parts)

Answer 6

• Shaft: made up of calamus and rachis
• Vanes: soft surfaces of the feather on either side of the rachis
• Barbs: emerge from rachis to form vanes arranged in parallel and spread diagonally outwards.
• Barbules: emerge from each barb and hold the barbs together

Question 7

Contour feathers

Answer 7

the outermost feathers that give the bird its form

Question 8

Down feathers

Answer 8

• soft tufts without a prominent rachis

* beneath contour feathers

Question 9

Filoplumes

Answer 9

• hairlike, degenerate feathers (hairs of a plucked bird)

* Function not known

Question 10

Powder downs

Answer 10

• Tips disintegrate as they grow releasing a talc-like powder
• Helps to waterproof feathers
• Characteristic of herons, bitterns, hawks and parrots

Question 11

Remiges

Answer 11

• Flight feathers
• Often largest contour feathers
• Attached by ligaments or directly to the bone

Question 12

Retrices

Answer 12

• Tail feathers
• Attached to each other by ligaments
• Only innermost are attached to the tailbone

Question 13

Coverts

Answer 13

• Small feathers that overlay and border reminges and retrices
• Help shape the wing and provide insulation

Question 14

Molting

Answer 14

• Remiges and retrices are molted in pairs, to maintain balance
• feathers are dead
• plumage can change with molting
• molting takes energy

Question 15

skeleton

Answer 15

-bones are hollow with air pockets
-skull is fused into one piece
-no teeth
-skeletons of birds and other animals are the same weight. Their weight distribution is different - they have a low center of gravity
-vertebrae are fused
-

Question 16

Arboreal hypothesis

Answer 16

• Evidence: extant flightless species which can glide • e.g. kakapo, flightless New Zealand parrot
• modifications for lift and powered flight would come later
• Weakness: few feathered dinosaurs were arboreal

Question 17

Cursorial hypothesis

Answer 17

-less likely
• Evidence: chukar partridge chicks use wingbeats to assist running up steep inclines
• Weakness: difficult to overcome gravity

Question 18

pneumatized

Answer 18

hollow bones with air cavities

Question 19

respiration

Answer 19

air sacs
continuous flow
parabronchi = alveoli = gas exchange