exam 1 Flashcards
(171 cards)
1
Q
Diagnostic characteristic
A
trait shared by all birds, but no other LIVING organisms
2
Q
Unifying characteristics
A
- reflect a common evolutionary history
- shared by all birds
- other organsims may also share these traits
3
Q
Evolution
A
species have changed over time and are related by descent from a common ancestor
4
Q
Name a diagnostic characteristic of birds
A
feathers
5
Q
Name at least 5 unifying characteristics of birds
A
1, Bills
2. Skeletal specializations - pneumatic bones, fusion/reduction of bones
3. Bipedalism - digitagrade feet (walk on toes)
4. centralized body mass for flight and balanced walk on land
5. High metabolism
6. specialized circulatory and respiratory systems
7. highly developed CNS and vision
8. large, nutrient rich eggs
9. loss of urinary bladder
10. Loss of teeth (replaced by gizzard)
6
Q
Natural selection
A
individuals that survive to reproduce will have higher fitness
7
Q
Adaptive radiation
A
process in which organisms diversify rapidly from an ancestral species into a multitude of new forms that fill new ecological niches
ex) galapagos finches diversified their bill shapes to fill new niches
8
Q
convergent evolution
A
evolution of shared characers due to similar ecological pressures NOT common ancestry (traits are analagous not homologous)
9
Q
Phylogeny
A
the evolutionary history of an organism
10
Q
Systematics
A
the field of study that seeks to reconstruct phylogenies
11
Q
Phyletic evolution
A
gradual change in a single lineage
12
Q
speciation
A
splitting of a single phyletic lineage into two or more
13
Q
extinction
A
termination of a lineage
14
Q
Biological species concept
A
a group of interbreeding or potentially interbreeding populations that are reproductively isolated from other groups
15
Q
Phenetics
A
organisms are grouped based on overall similarity without regard to evolutionary history
16
Q
Cladistics
A
some traits are more useful than others in determining relationships, particularly shared, derived traits
17
Q
Phylogeny
A
an evolutionary history of a group of taxa described as an evolutionary tree (cladogram) with a common ancestor at the base and descendent taxa at the branch tips
18
Q
The word ‘taxa’ can describe
A
a population, subspecies, species or genera
19
Q
What types of characters should you chose in cladistics?
A
homologous characters (show the clearest evolutionary relationships)
20
Q
Homologous trait
A
a trait that is derived from a common ancestral trait
21
Q
Analagous trait
A
does not show an evolutionary relationship between two animals - appears similar due to convergent evolution
ex) bird wing and insect wing
22
Q
Synapomorphy
A
shared, derived traits - define a monophyletic group
23
Q
Symplesiomorphies
A
shared among all taxa in a phylogeny due to its evolution in a common ancestor
ex) in birds, this might be feathers
24
Q
Homoplasies
A
are analagous traits OR reversals
25
What type of traits are the most useful for classifying high level taxonomic categories?
conserved characteristics
26
Name some conserved characteristics that can help determine taxonomy in birds
1. bony palate - separates paleognathae from neognathae
2. nares
3. structure of leg and foot muscles
4. morphology of vocal apparatus
5. behavior
6. vocalizations
7. downy chick plumage
8. toe arrangement
27
Parsimony
the principle that the most likely explanation is the simplest one - the cladogram that is most likely to be closest to reality is the one with the fewest transitions (losses/gains of traits)
this is based on the assumption that synapomorphies are more common than homoplasies
28
Monophyletic group
includes the most recent common ancestor of a group of organisms and ALL OF ITS DESCENDANTS
29
polyphyletic group
does not include the common ancestor of all members of the taxon
30
paraphyletic group
includes the most recent common ancestor, but not every descendant
31
Reptiles and birds describe this type of phylogenetic group
monophyletic group
32
reptiles describe this type of phylogenetic group
paraphyletic group
33
warm blooded animals (mammals/birds) describes this type of phylogenetic group?
polyphyletic group
34
Name some steps in the evolution of modern birds
1. reversed hallux - grasping or perching foot
2. tarsometatarsus - fused leg bones
3. carpometacarpus - fused wrist and hand bones
4. pygostyle - shortened tail vertebrae/fusion of bones
5. keeled sternum - attachment of flight muscles
6. modern coracoid - modified shoulder joint allows movement of wing above head
7. alula - facilitates flight by reducing turbulence, esp. during slow flight
35
This group of birds that occured 'after archaeopteryx' is now extinct
Enantiornithine birds
36
What are some characteristics of Enantiornithines? (6)
1. most abundant and diverse group of avialans in the cretaceous period
2. additional modifications for flight
3. modern perching foot
4. advanced forelimb modifications (raise wings over body and fold them)
5. retained teeth and clawed fingers on each wing
6. NOT ancestors of modern birds
37
Name some characteristics of ornithurae birds (2)
1. uncinate processes connect ribs and protect thoracic cavity
2. loss of teeth
38
Name 2 branches of extinct ornithurae birds
1. Hesperornithiformes - toothed diving birds with larged lobed feet
2. Ichthyornithiformes - flying toothed seabirds - like terns
39
Name the ancestors of modern orders that survived the mass extinction (2)
1. Paleognathae - ratites/tinamous
2. Neognathae
- Galloanserae (Galliformes - turkey and quail + Anseriformes - ducks)
- Neoaves (procellariiformes - petrels and albatross + shorebirds - sandpipers and plovers)
40
Feathers
unique epidermal structure composed of a special class of beta-keratins
41
Types of feathers (7)
1. contour feathers
2. flight feathers
3. down
4. semiplumes
5. filoplumes
6. bristles
7. powderdowns
42
Name the two types of vaned feathers
1. contour feathers
2. flight feathers
43
Calamus
the bare part of the feather where it attaches to the bird
44
Vane
the part of the feather that is connected to the rachis
45
Pennaceous structure
interlocking barbs
46
Barb
the part of the feather that branches from the rachis, including the ramus, barbule and barbicel
47
What is the relationship between the barbule and barbicel
barbicels are hooklike structures that protrude from the barbules
48
What are some characteristics of contour feathers
1. feathers that cover the body and wings
2. may have an aftershaft
3. symmetrical vanes
49
What are the 2 types of wing feathers
1. primaries attach to the bones of the hand and second digit (fused)
- primaries are numbered starting at ten (X) on the leading edge all the way down to 1 - BIRDS ONLY HAVE 10 PRIMARIES
2. secondaries - number of secondaries may vary from like 8 to 35 and are numbered in the opposite direction from the primaries (increasing in number towards the body)
50
Coverts
- cover calami of remiges
- help body be more aerodynamic
- overlap like shingles on a roof
- flight feathers mostly hidden on closed wing
51
Why are flight feathers asymmetrical?
the leading edge of the feather has a narrow vane to increase stiffness and rigidity and provide lift
flight feathers with coverts combine to make the entire shape of the wing an assymetrical, curved structure to facilitate lift
52
How are the remiges numbered?
Primaries are numbered 1-10 with 10 being the most distal and 1 being the most proximal
Secondaries are numbered 1-n with 1 being the most distal and n being the most proximal
53
What are the remiges
Wing feathers
54
What are the retrices?
Tail feathers
55
How are the retrices attached?
Attached via ligaments to the pygostyle
56
Are the retrices pennaceous or plumulaceous?
Pennaceous
57
Name the 2 types of pennaceous feathers
1. Flight feathers (retrices/remiges)
2. Contour feathers
58
What is the function of the retrices?
Steering and landing
Can disrupt airflow to decelerate, or spread/narrow/tilt tail to steer
59
What are the characteristics of a down feather?
No central rachis
Barbules lack barbicels
Plumulaceous
Thermoregulatory function
Reduced or absent rachis
60
Natal down
Occurs in young birds, grows in feather tracts and is eventually replaced with contour feathers
61
Adult down
Occurs all over the body, not just in tracts
62
What are some characteristics of a semiplume?
-No barbicels
-Plumulaceous
-Traps air (thermoregulatory fct)
-The rachis is longer than the longest barb - KEY CHARACTERISTIC
63
What are some characteristics of a filoplume?
-Sensory feather with tuft at the tip of the feather
-hairlike
-touch receptors in the skin next to the feather
-fct theorized to be detecting wind speed and direction
64
What are some characteristics of a bristle?
-sensory feather with tuft at the base
-occur around eyes and bills
-connected to sensory corpuscule at the base
-tactile and protective function (like eyelashes)
65
Ramus
-the main part of the barb
-barbules attach to the ramus, which extends perpendicular to the rachis
66
What is the function of rictal bristles?
To funnel food towards the mouth and to compensate for reduced vision when feeding at night
67
What is unique about the feathers of a sandgrouse?
Males soak up water for chicks to drink out of his belly feathers - like a sponge
68
What is unique about the feathers of club winged manakins?
They rub their wings together to create sounds and court females
69
How to hummingbirds court females?
They do courtship dives that force air through their retrices, making a sound
70
What are the two ways that feathers can have color?
Pigment and structure
71
Pigment
A naturally occurring substance incorporated into the feather that absorbs some wavelengths and reflects others
72
Structure (referring to color)
Typically a melanin layer, overlaid by air bubbles that change the wavelengths of light absorbed and reflected by a feather
73
Melanin
Synthesized from AA tyrosine in melanocytes
Can be deposited to form patterns
74
What are the two types of melanin?
Eumelanin - brown/grey/black
Phaeomelanin - tans, red-brown, yellow
75
Why is melanin beneficial to birds (besides colors)
Melanin increases structural integrity and resists bacterial colonization
76
Carotenoids
-Produced by plants and consumed in the diet as beta carotene and lutein and deposited in keratinocytes
-red, orange, and yellow pigments
77
Carotenoids
-Produced by plants and consumed in the diet as beta carotene and lutein and deposited in keratinocytes
-red, orange, and yellow pigments
78
Psittacofulvin
Parrot specific pigment, derived from carotenoid
79
Porphyrin
Chemically related to hemoglobin and liver bile pigments
80
Turacin and turacoveridin
Red and green pigments respectively, present in turacos
81
What are the two types of structural color?
Non iridescent and iridescent
82
Non iridescent structural color
- same color from every angle
-air pockets in feathers scatter specific wavelengths
- larger nanostructure scatters longer wavelengths, making redder colors
- smaller nanostructure scatters shorter wavelengths, making bluer colors
83
Iridescence
-Color changes depending on angle
- arrays of melanomas in beta keratin of the barbules
- made up of many layers of keratin and melanin rodules
84
Can birds use a combination of structural and pigmented colors?
Yes - paradise tanager uses structural color and carotenoids in their crowns
85
Could you say with certainly that a feather is white due to its pigment?
No - you cannot tell visually for most colors what the source of the color is
86
What weighs more, the feathers or skeleton of a bird?
Feathers
87
Pterylae
The feather tracts - feathers grow from follicles here
88
Apteria
Fatherless areas between tracts
89
Can a feather heal from trauma?
No - feathers are not alive and must be replaced
90
Uropygial gland
Gland at base of tail that produces preen oil - a substance that is spread over feathers to protect them from wear and parasites
91
Anting
Inviting ants to come up in your feathers and eat the parasites
92
Molt
Regular, scheduled replacement of feathers
93
Describe molt
1. Natal down
Pre juvenal molt - grow first set of contours
2. Juvenal plumage
1st pre basic molt
3. 1st basic plumage (sometimes only contour feathers get replaced and the bird can be aged here)
2nd prebasic molt
4. Definitive basic plumage
Prebasic molt
94
Describe molt for a bird that molts twice in a year
1. Natal down
Prejuvenal molt
2. Juvenal plumage
1st prebasic molt
3. 1st basic plumage
1st pre alternate molt
4. 1st alternate plumage
2nd prebasic molt
5. Definitive basic plumage
95
Molt limit
Occurs when a bird can be aged based on its feathers
Ex) 1st spring indigo buntings
96
How can plumage change without molt?
Starling plumage wears down to change color - white spots wear off
Sparrow badge of status shows when feathers wear down
97
Factors that influence frequency of molt
1. Habitat - exposure to sand, sun or wind wears down feathers
2. Parasite load - wears down feathers faster
3. Migration - causes wear on feathers
4. Life history - number of years until sexual maturity
98
Chord
Straight line width of an airfoil leading to the trailing edge
99
Camber
Convex shape of an airfoil in cross section - greater closer to body than at wingtip
Proximal camber > wingtip
100
Angle of attack
Angle at which the leading edge meets the flow of air
101
Bernoulli effect
Pressure decreases as speed increases - helps birds achieve flight as air moves over the wing faster than under
102
Newtons 3rd law
Camber shape directs air down, causing an equal and opposite force generating lift
103
How does the angle of attack help generate lift?
Greater angle of attack = more air directed downward = greater lift
Too much angle, and you stall though
104
Thrust
Forward component of lift
105
Downstroke generates...
Thrust
106
What is the most efficient speed of flight
Intermediate speed
(Faster and slower flight are both more energetically expensive)
107
How do birds generate lift?
Wing shape and position
108
What is thrust and how do birds generate it?
Forward component of lift and by changing wing position
109
What are the two types of soaring?
Thermal and dynamic
110
Thermal soaring
Ride rising air with very little energy
111
Dynamic soaring
Exploits differences in wind speed caused by waves/ridges
Turn into wind to gain altitude
Gain speed by gliding down
Ex) albatross
112
Flapping
Allows each primary to act as an airfoil
On the upstroke, primaries separate to reduce resistance
113
Alula
Feathered digit #1, allows birds to control movement of air over the top of the wing to maintain lift and prevent stalling at slow speeds or high angle of attack
- prevents turbulent flow and promotes laminar flow (keeping air stuck to the wing)
Most useful at slow speeds or during landing
114
What are the two types of intermittent flight?
1. flap glide - reduces power cost at slower speeds
2. flap bounding - reduces power cost at faster speeds
115
What type of intermittent flight reduces power cost at low speeds?
flap gliding
116
What type of intermittent flight reduces power cost at high speed?
flap bounding
117
What is unique about hummingbird flight?
they produce lift and thrust on the upstroke and on the downstroke
118
What do hovering birds do to prevent stall?
extend the alula and spread the tail
119
Wing loading
body mass/wing surface area
increased body size = increased wing loading
increased wing loading = increased energy expense
decreased wing loading = fly slower and with less flapping
120
Aspect ratio
wingspan/wing surface area
high aspect ratio = high lift, lower drag, and lower maneuverability
low aspect ratio = less lift, less drag, and more maneuverability
121
What are the four broad categories of wing shape?
1. slotted high lift - eagle, RTHA
2. high aspect ratio - albatrosses and gulls
3. elliptical wings - crow, grouse, sparrow
4. high speed wings - falcon, duck, swift
122
Describe a slotted high lift wing in terms of aspect ratio and wing loading
- medium aspect ratio
- low wing loading
- notched feathers to reduce drag and generate lift
- generous use of alula
123
describe a high aspect ratio wing in terms of aspect ratio and wing loading
- high aspect ratio
- high speed gliding in high wind speeds
- narrow and unslotted wings
- moderate wing loading
- difficult takeoff and not very maneuverable
- increased lift and increased speed
- birds spend most of their lives soaring
124
What are the two categories of elliptical wings and what do they do?
- low aspect ratio/low wing loading
- drag offset by slotting, high maneuverability in dense habitat
- crow, sparrow, songbirds
- low aspect ratio/high wing loading
- good at bursting flight/not great at sustained flight
- grouse, quail
125
What are some characteristics of high speed wings?
- medium aspect ratio
- high wing loading
- pointed wing tips and swept back wings
- need to flap to generate lift, have good maneuverability in open habitat
- falcons, swifts, ducks
126
What are the names of the two muscles that facilitate flight and are attached to the keel?
the pectoralis and the supracoracoideus
127
Which flight muscle is responsible for the downstroke?
the pectoralis
128
Which flight muscle is the largest in most species?
the pectoralis
129
Which flight muscle is responsible for the upstroke?
the supracoracoideus
130
Which birds have a large supracoracoideus?
hummingbirds and penguins
131
arboreal theory
flight began with gliding from tree - tree
ie) originated with the arboreal lifestyle
132
cursorial theory
elongated limbs and leaping made it easier to catch prey
ie) flight benefits predation
133
wing assisted incline running
flying evolved gradually to assist with climbing up inclines
134
What are the three different theories for how flight developed?
arboreal theory, cursorial theory, and wing assisted incline running
135
endotherm
body heat is produced endogenously
ex) mammals, birds
136
ectotherm
relies on the environment to generate body heat
137
polikotherm
body heat fluctuates with the environment
138
homeotherm
maintain their body temperature within a narrow range
139
all _______ are homeotherms, while some _______ are polikotherms and some are homeotherms
endotherms, ectotherms
140
what are some costs and benefits of endothermy?
costs - energy expensive, prone to overheating, higher protein requirements
benefits - active at many temperatures, increases speed of nerve impulses, increases muscle fiber contraction strength, increases endurance
141
basal metabolic rate (BMR)
the minimal energy requirement of resting, non-stressed birds at neutral temperatures
142
does BMR scale with size?
no, the larger the bird, the lower the BMR
ie) the ratio of BMR:size is larger for small birds and smaller for large birds
143
What types of activites increase the metabolic rate
extreme temperatures, reproduction, molting and flight all have metabolic costs
144
thermoneutral zone
the temperature range within which extra energy is not expended to thermoregulate
145
lower critical temperature
the coldest it can be before a bird needs to start doing something to thermoregulate
146
upper critical temperature
the hottest it can be before a bird needs to start thermoregulating
147
what happens at temperatures above the upper critical temperature (UCT)?
evaporative cooling
148
What happens at temperatures below the lower critical temperature?
shivering occurs
149
what are some things birds can do to thermoregulate in cold temperatures (6)
1. fluff contour feathers to trap air
2. tuck extremeties close to body
3. change the microclimate (burrow into snow, get close to buildings)
4. huddling
5. communal roosting
6. increase the metabolism
150
what is the process by which birds become accustomed to more extreme environments (like the cold)
acclimation
151
torpor
dropping of body temp to closely match the environmental temp, usually down to like 8c
152
what are some costs and benefits of torpor?
costs
- cannot respond to threats
- time and energy investment in waking up from torpor
benefits
- conserve energy
153
What is countercurrent heat exchange?
blood vessels carrying warm blood are closely associated with blood vessels carrying cold blood
blood returning to the body is warmed and blood going to the feet is cooled
in this way, the feet are kept just above freezing and heat is conserved
this system can be bypassed in hot environments to lose heat in the legs
154
How do birds use facultative hyperthermia?
Birds use facultative hyperthermia to reduce heat gain from the environment, reduce water loss and conserve energy
raising the body temperature more than one or two degrees celcius is not good because it denatures protiens and can be fatal
155
What are some behavioral ways that birds can reduce their body temperatures
1. reduce activity during hottest times
2. find a better microclimate (think grackles under cars)
3. soar at high altitudes to find cool air
4. panting and gular fluttering
5. ruffle feathers to expose apteria (bare skin between pterylae - feather tracts)
6. expose legs
156
What are some ways that birds dissipate heat? (not behavioral)
- beak dissipates heat
- evaporative cooling
157
Allen's rule
appendages of endotherms are smaller relative to body size in colder climates
158
What size of bird is more vulnerable to heat stress
larger birds
159
Bergman's rule
animals are larger in cold climates and small in warm climates
160
House finches spread across the united states in a short period of time. What rule can we use to predict the body size these house finches?
bergmann's rule
161
What are the differences between mammal respiration and bird respiration
mammals
- diaphragm
- chest cavity at lower pressure than the environment
- tidal breathing
- 50% volume inhaled does not participate in gas exchange
birds
- no diaphragm
- air sacs store and pump air
- air flows in a single direction
- air intake on inspiration and expiration
162
how many air sacs are there?
4 pairs of air sacs, one unpaired and smaller air sacs in the bones
163
what is the function of the air sacs?
enhance airflow
dissipate body heat during flight
cushion internal organs during flight
may be used in mating displays (frigatebird)
gas exchange DOES NOT OCCUR
164
if birds do not have a diaphragm, how do they breathe?
via the movement of the ribs and sternum to change the size of the thoracic cavity
165
what is the path of air through a bird's respiratiory system?
1. nares
2. trachea
3. posterior air sacs
4. lungs (primary bronci/mesobronchi -> secondary bronchi -> tertiary bronchi (parabronchi))
parabronchi are the site of gas exchange
166
Describe what happens as air moves through a bird's respiratory system?
1. inhalation - air moves to posterior air sacs
2. exhalation - o2 rich air moves to lungs for gas exchange
3. inhalation - co2 rich air from lungs moves to anterior air sacs
4. exhalation - air is expelled from anterior air sacs
167
What are the functions of a bird's circulatory system?
1. distribute food from the digestive tract to the body
2. distribute O2 from the lungs to the body
3. remove CO2 from tissues and get rid of it
4. remove wastes
5. dissipation and conservation of heat
168
If you control for body size, what is the relationship between mammal and bird heart rate/heart size/stroke volume
heart rate - mammalian heart rates are typically faster than a bird's
heart size - hearts of birds are 41% larger than mammals when controlling for body size
stroke volume - mammalian stroke volume is smaller, bird stroke volume is larger
169
What is the difference between white and dark meat?
'dark' meat has more myoglobin due to sustained muscle activity (cells use sustained aerobic cell respiration)
170
Could we expect the breast meat from a migratory bird to be the same as the breast meat from a domestic terrestrial bird?
No, the breast meat of a terrestrial bird is likely to be 'white meat' and have less myoglobin
the breast meat of a migratory bird is designed for endurance/sustained activity, thus is will have more myoglobin and be 'dark meat'
171
What does a salt gland do?
in seafaring birds, the salt glands allow birds to get rid of excess salt from the nares instead of relying on the kidneys
these birds must drink salt water to survive
