Lab 8. Aves

Question 1

Features shared between reptiles and aves

Answer 1

• Scales on legs
• Single occipital condyle
• Lower jaw = 5 fused bones
• Gizzard
• Metanephric kidney
• Nucleated erythrocytes
• single middle ear bone
• amniotic egg and egg tooth
• parental care

Question 2

Integument Feathers general

Answer 2

• lift and steering during flight
• insulation, endothermic maintenance of high metabolic rate
• waterproofing
• courtship, camouflage, species recognition

Question 3

3 types of feathers

Answer 3

1. Pennaceous
2. Plumaceous
3. Filoplumaceous

Question 4

Filoplumaceous

Answer 4

lack barbs/barbules along most of length

sensory role

Question 5

Plumeaceous

Answer 5

“down”
rudimentary shaft with barbs and barbules that don’t interlock
insulation

Question 6

Pennaceous

Answer 6

prominent rachis, barbs branch out.

overlapping barbules branch out from barbs, joined by hamuli (hooks) that keep them firm and smooth

Question 7

2 types of pennaceous

Answer 7

1. Flight feathers

2. Contour feathers

Question 8

Flight feathers

Answer 8

asymmetrical
leading edge shorter than lagging edge
bend without twisting
flight

Question 9

Contour feathers

Answer 9

symmetrical, line body and cover base of wings

waterproofing, insulation, streamlining

Question 10

Remiges

Answer 10

flight feathers

Question 11

Retrices

Answer 11

tail feathers

Question 12

Moulting

Answer 12

Feathers moult. Sometimes birds can’t fly during moulting, some only moult some flight feathers at a time so they can still fly

Question 13

4 key skeletal modifications

Answer 13

1. Lightweight skeleton
2. Strong and rigid skeleton
3. increased bone surface area
4. Flexible neck

Question 14

Lightweight skeleton

Answer 14

large internal spaces strengthened by strutting

reduced number of skull bones and lightweight bill

Question 15

Increased bone surface area

Answer 15

accomodate flight muscle attachement (like keel)

Question 16

Flexible neck

Answer 16

allow range of movement because forelimbs can’t be used for manipulation

Question 17

Food acquisition and digestion

Answer 17

Eat lots due to high metabolic rate and endothermy

Bills modified to exploit habits and food sources

Question 18

Sensory abilities

Answer 18

Complex sensory and motor system due to flight

Complex learning capabilities and social behaviour

Question 19

Reproduction

Answer 19

Internal fertilization, cloacal contact transfers sperm
Oviparous
Intricate mating behaviours
High parental care investment

Question 20

Gas exchange

Answer 20

• Consume more O2 than any other vertebrate so very efficient
• No “dead air”
• Unidirectional respiratory system
• Air sacs (blind, thin-walled destensible extensions of lungs in all major parts of body, no direct role in gas exchange)
• 2 cycles

Question 21

Respiration cycles

Answer 21

cycle 1

• inhalation: o2 air enters nares, through trachea, bronchi, into abdominal air sacs
• exhalation: air goes to parabronchi, o2 goes into blood stream

Cycle 2

• inhalation: moves to thoracic air sacs
• exhalation: expelled from body

They overlap

Question 22

uropygial gland

Answer 22

produces oil for preening to make waterproof feathers

Question 23

Nitrogenous waste

Answer 23

uric acid

Question 24

4 types of beaks

Answer 24

1. generalist
2. raptorial
3. chiseling
4. flattened

Question 25

Generalist

Answer 25

cracking seeds

Question 26

raptorial

Answer 26

hooked for tearing flesh

Question 27

chiseling

Answer 27

long for digging out insects

Question 28

flattened

Answer 28

filtering and fishing

Question 29

Slow phase muscle

Answer 29

red (turkey vulture)

Question 30

Fast phase muscle

Answer 30

white (ruffle grouse)

Question 31

Order of pigeons

Answer 31

Columbidae

Question 32

Are pigeons perching birds

Answer 32

no

Question 33

cloaca

Answer 33

releases excretory and genital products

Question 34

Olfaction?

Answer 34

most birds don’t rely on it but pigeons use it for homing maybe

Question 35

keel

Answer 35

extension of sternum, large surface for pectoral muscles in flying birds

Question 36

furcula

Answer 36

wishbone
fusion of 2 clavicles
strengthens thoracic skeleton to withstand flight

Question 37

pygostyle

Answer 37

triangular plate made of caudal vertebrae. supports tail feathers to steer

Question 38

tarsometatarsus

Answer 38

fusion of tarsal and metatarsal bones used to accelerate for takeoff

Question 39

crop function

Answer 39

• temporarily store food

- crop milk

Question 40

crop more developed in insect or grain birds

Answer 40

grain cause they can hold lots many grains at once and then leave to digest in safer place. Hard to get big amounts of food as predator

Question 41

In crop what do you see

Answer 41

undigested food

Question 42

what is ventriculus

Answer 42

“gizzard” helps mechanically break down food with stones