Feathers and Flight Flashcards

1
Q

What is a pennaceous feather?

A

A feather with a stalk and calamus.

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2
Q

What is the central stalk of a bird feather called?

A

The rachis.

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3
Q

What are the small things that extend from the rachis in a feather called?

A

The barbs.

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4
Q

True or false? Some dinosaurs had feathers.

A

True.

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5
Q

What do feathers help a bird to do?

A

Fly, insulate themselves, waterproof themselves, camouflage, and attract mates.

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6
Q

Where are feathers formed?

A

In tiny follicles in the epidermis.

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7
Q

What are feathers made of?

A

Beta keratins.

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8
Q

What kinds of bonds create the protein strands necessary to create beta keratins?

A

Hydrogen bonds.

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9
Q

Name the parts of the feather.

A
  1. Vane
  2. Rachis
  3. Barb
  4. Afterfeather
  5. Calamus
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10
Q

What are the two basic kinds of feathers?

A

Vaned feathers and down feathers.

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11
Q

Where are down feathers?

A

Beneath the vaned feathers.

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12
Q

What connect the barbs of a feather together?

A

Tiny barbules.

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13
Q

True or false? Pennaceous feathers are down feathers.

A

Fale. They are vaned feathers.

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14
Q

What is another name for pennaceous feathers?

A

Contour feathers.

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15
Q

What is a filoplume?

A

A hairlike feather that grows along the fluffy down feathers.

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16
Q

What are the remiges?

A

The flight feathers on the wing.

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17
Q

What are the retrices?

A

The flight feathers on the tail.

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18
Q

Are the retrices or remiges more important for flight?

A

Retrices.

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19
Q

What is the main shaft or stalk of a feather called?

A

The rachis.

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20
Q

What is the hollow base of a feather called?

A

The calamus.

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21
Q

What are the special down feathers of young birds called?

A

Neossoptiles.

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22
Q

In what special way are flight feathers stiffened?

A

They are stiffened so they work against the air on the downstroke, but yield in other directions.

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23
Q

How wil some birds keep their eggs and young warm?

A

They wil line the nest with their feathers.

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24
Q

True or false? The feathers of a bird weigh more than its skeleton.

A

True.

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25
Q

Why do some birds have different colored feathers on their top and bottom?

A

To camouflage them in flight.

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26
Q

What is the special “dark to and light bottom” camoflage type called?

A

Countershading.

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27
Q

True or false? Male birds look the same to females as they do to us.

A

False. Birds can see UV light, so the males appear more colorful depending on if they have UV reflecting feathers.

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28
Q

What is powder down used for?

A

It waterproofs and conditions the feathers.

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29
Q

Where does powder down come from?

A

It breaks off from the end of the barbules.

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30
Q

What is the main way birds lose their waterproofing?

A

Exposure to pollution.

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31
Q

Why is waterproofing very important in birds that live on the water?

A

Their feathers become waterlogged without it and they sink.

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32
Q

What is unusual about the feathers of the cormorant?

A

They soak up water to allow them to dive better.

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33
Q

Describe bristle feathers.

A

They are stiff with large rachis and few barbs.

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34
Q

What are rictal bristles?

A

Bristles that are found around the eyes and bill.

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35
Q

What purpose do rictal bristles serve?

A

They act like eyelashes.

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36
Q

What interesting behavior do grebes exhibit with their feathers?

A

They eat their feathers and feed them to their young.

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37
Q

What is the main theory as to why grebes eat their feathers?

A

To help them form pellets.

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38
Q

True or false? Contour feathers are evenly distributed throughout the skin.

A

False. Only penguins, screamers, and some other rare exceptions have evenly distribured feathers.

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39
Q

What are the specific tracts of skin that feathers grow from called?

A

Pterylae.

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40
Q

What are the tracts of skin that no feathers grow from called?

A

Apterylae.

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41
Q

What is pterylography?

A

The arrangement of feathers on a bird.

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42
Q

What is pterylography used for?

A

Determining evolutionary relationships in bird families.

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43
Q

What produces the colors in feathers?

A

Pigments.

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44
Q

What is structural coloration?

A

The production of colors by structures fine enough to interfere with visible light.

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45
Q

Peacock tail feathers appear green and blue, but structural coloration is responsible for this illusion. What color are they pigmented?

A

Brown.

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46
Q

Who first observed structural coloration?

A

Isaac Newton and Robert Hooke.

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47
Q

What principle causes structural coloration?

A

Wave interference

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48
Q

What is irridescence?

A

When things appear to change color as the angle of view changes.

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49
Q

How was structural coloration discovered?

A

Robert Hooke noted that a peacock’s feather lost its irridescence when it was plunged into water, but regained it when exposed to the air.

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50
Q

What are two everyday examples of structural coloration and irridescence?

A

One-way mirrors and CDs.

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51
Q

What structures cause structural coloration in animals?

A

Diffraction gratings, selective mirrors, photonic crystals, and matrices of proteins.

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52
Q

True or false? It is possible to see the structures that cause structural coloration with the naked eye.

A

False. An electron microscope is needed. Many of these optical tricks occur at a cellular level.

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53
Q

What is a diffraction grating?

A

A component with a structure that splits and diffracts light in several different directions.

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54
Q

What is a photonic crystal?

A

A nanostructure that affects the motion of photons.

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55
Q

What is a photon?

A

It is a quantum of light or radiation. It has zero mass, but contains energy.

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56
Q

What si the difference between albinos and leucistics?

A

Albinos only have reduced melanin production. Leucistics have reduced production of all pigments.

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57
Q

What feather structure causes structural coloration that appears yellow or green?

A

The Dyck structure.

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58
Q

What gland on a bird produces oil that can cause irridescence on them?

A

The uropygial gland.

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59
Q

What is a pin feather? (Also called a blood feather)

A

A developing feather.

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60
Q

When do pin feathers grow?

A

During infancy or replacements.

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61
Q

What does a pin feather look like?

A

A feather shaft.

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62
Q

What will happen if a pin feather is damaged?

A

The bird will begin to bleed.

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63
Q

What happens as a pin feather grows longer?

A

The blood supply is concentrated to only the base of the feather and the feather itself is covered in a waxy coating. The birds then preen and remove this coating and the feather unfurls.

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64
Q

What follicles do pin feathers form from?

A

The same ones that the old feathers came from.

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65
Q

When studying the evolution of feathers, what possible functions do scientists focus on?

A

Insulation, display, and flight.

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66
Q

What do darker feathers resist better than lighter ones?

A

Bacteria.

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67
Q

Why do brighter colors in a bird attract more mates?

A

Healthy birds have brighter colors, so it is a sign of fitness.

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68
Q

What is anting and why do birds do it?

A

Anting is the process of a bird rubbing ants or other insects on its feathers. No one is sure why they do it, but the two theories are that birds either do it to kill parasites on their feathers or render the insects edible by making them release the acids there.

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69
Q

What are the three main ways birds maintain their feathers?

A

Preening, bathing, and dust bathing.

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70
Q

What kinds of parasites do birds most commonly host?

A

Feather lice and feather mites.

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71
Q

Where does the word “pen” come from?

A

The Latin word “penna”, meaning feather.

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72
Q

True or false? Feathers are slow to decompose.

A

True.

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73
Q

What is the eagle feather law?

A

A law that allows only registered members of Native American tribes to be in posession of eagle feathers.

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74
Q

What are the feathers of the Indian peafowl used to treat in Indian tradition medicine?

A

Snakebite, infertility, and coughs.

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75
Q

What is the Lacey Act of 1900?

A

An act introduced by John F. Lacey (R) to President McKinley that prohibited trade in wildlife or plants that had been illegally obtained.

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76
Q

What kind of feathers are the feathers used in modern hair accessories?

A

Rooster feathers.

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77
Q

What kind of feathers do South American natives use in their medicines?

A

Condor.

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78
Q

Why are feathers most often used in high class bedding?

A

They are soft and trap heat easily.

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79
Q

What kind of feathers are best for insulation and bedding?

A

Down feathers.

80
Q

What most prominently led to the establishment of the Lacey Act?

A

A campaign against the extravagant headdresses worn by women at the time. It was depleting the bird populations exponentionally.

81
Q

Why is the feather market in Europe decreasing so drastically?

A

New regulations and competition from asia.

82
Q

What law caused the feather market to collapse in the USA?

A

The Lacey Act.

83
Q

Discoveries of feathered dinosaurs in China indicate that the original purpose of feathers may not have been flight. What are the three most likely original uses?

A

Waterproofing, insulation, or as areas to store metabolic waste.

84
Q

What is evolutionary developmental biology (evo-devo)?

A

A science that compares the developmental biology of different animals to determine the ancestral relationships between them.

85
Q

What are some topics evo-devo covers?

A

The origin and evolution of embryonic development, how modifications of deveopmental processes lead to new features in an organism, phenotypic pasticity, and how ecology impacts development and evolution.

86
Q

What is phenotypic plasticity?

A

The ability of an organism to change its observable traits in response to changes in the enviornment.

87
Q

Why do scientists think that the original purpose of feathers is thermoregulation?

A

Smaller birds hve more feathers per square inch than larger birds. Since smaller birds lose heat faster, they need more feathers.

88
Q

What did the downsizing of birds help to do?

A

It helped to evolve powered flight.

89
Q

What is the coloration of a birds feathers believed to have evolved in respose to?

A

Mate selection.

90
Q

In 2006, it was discovered that ____ is present in the early stages of development in American alligator scales.

A

Feather keratin.

91
Q

Why do adult American alligators not hav feather keratins?

A

The feather keratins are destroyed during embryonic development.

92
Q

What does the presense of the homologous keratin in birds and crocodiles suggest?

A

It suggests that they shared a common ancestor.

93
Q

What are oviraptors and what traits did they have?

A

One of the links between dinosaurs and birds. They had feathers, a parrot like beak, and a shortening tail.

94
Q

Where did the oviraptor have feathers?

A

Forelimbs and tails.

95
Q

Why has it been deduced that the feathers on the oviraptor are much like modern pennaceous feathers?

A

The have a rachis and a herringbone pattern of barbs.

96
Q

What is anchiornis?

A

A genus of small, feathered dinosaurs.

97
Q

Explain the temporal paradox.

A

Feathered dinosaurs such as deinonychus are considered to be the ancestors of modern birds, but by the time deinonychus existed, birds had already developed.

98
Q

How was the temporal paradox resolved?

A

The discovery of anchiornis. It showed that there was a theropod ancestor that was modernly feathered. Therefore, one branch of theropods may have become birds while the others became species like the deinonychus.

99
Q

How were scientists able to figure out the full coloring of anchiornis?

A

There were preserved pigments in its fossil.

100
Q

How many different species of birds were used in ladies’ hats at the height of the “Bird Hat” craze?

A

40

101
Q

What percentage of ladies hats were made from dead birds during the “Bird hat” craze?

A

75%

102
Q

Who were Xu and Guo?

A

Two scientists who put forth the first ideas as to the evolutionary development of feathers.

103
Q

What is pinioning?

A

The removal of the pinion joint (the wing joint farthest from the bird’s body) to prevent flight.

104
Q

Who built upon Xu and Guo’s work?

A

Forth.

105
Q

What kinds of birds is pinioning used on?

A

Waterfowl and poultry.

106
Q

Why does pinioning keep birds from flying?

A

It stops the growth of the primary flight feathers.

107
Q

True or false? Pinioning can be done by anyone and is legal in most places.

A

False. It is illegal in most countries and can only be performed by licensed breeders or vets.

108
Q

Do male or female chickens have slightly faster feather growth?

A

Female.

109
Q

What two forces do flight feathers generate that allow birds to fly?

A

Thrust and lift.

110
Q

What allows owls to fly silently?

A

Tiny serrations on their remiges.

111
Q

What are the two main strategies birds use for coping with the flightlessness that moult causes?

A

They shed all their feathers at once, or they stagger the moult over a very long time.

112
Q

What connects the calamus of a bird’s feather to the wing bone?

A

Ligaments.

113
Q

What is the name of the tissue that holds the remiges in place?

A

The postpatagium

114
Q

What is a manus?

A

The end of an animal’s forelimb.

115
Q

True or false? Primaries are the lonest and narrowest of the remiges.

A

True.

116
Q

What is special about the primaries that allows birds to control their flight?

A

They can be individually rotated.

117
Q

What force do the primaries generate in a birds wing?

A

Thrust.

118
Q

When a birds flaps it wings, is thrust generated mostly on the downstroke or upstroke?

A

Downstroke.

119
Q

How does a bird still manage to generate some thrust on the upstroke?

A

They rotate their primaries and reduce air resistance.

120
Q

What are the special barbules on primary feathers called?

A

Friction barbules.

121
Q

What do friction barbules help to prevent?

A

Feather slippage.

122
Q

How many primaries do most birds have?

A

9 - 11

123
Q

What are the outermost primary feathers called?

A

Pinions.

124
Q

What are secondary feathers connected to?

A

The elbow bone.

125
Q

True or false? Secondary feathers can be seperated just like primaries.

A

False.

126
Q

What force do secondary feathers help to create and how?

A

They create lift by creating an aerofoil shape.

127
Q

As wingspan gets larger, the number of secondaries ______.

A

Increases.

128
Q

What is the purpose of tetrices and tertials?

A

They protect the flight feathers and sometimes are used for decoration. (In the case of the peacock)

129
Q

What is an emargination?

A

A small gap within the feathers of a bird’s wing that allows them a little extra lift so that they can glide.

130
Q

What kinds of birds have the largest emarginations?

A

Raptors.

131
Q

What does the alula help with and where is it attatched?

A

It attatched to the to of the bird’s wing and it allows them to slow their flight.

132
Q

What are the main functons of the retrices in flight?

A

Braking and steering.

133
Q

True or false? All the retrices are attached to the bone.

A

False. Only the innermost pair are.

134
Q

Besides the innermost pair, what are most rectrices attached to?

A

Fat and muscle.

135
Q

What is the purpose of some birds having flight feathers that make sounds?

A

Courtship and territorial displays.

136
Q

What makes the whistling and twittering sounds when a male woodcock flies?

A

His outer primary feathers.

137
Q

What is stridulation?

A

The act of making sound by rubbing together body parts.

138
Q

What is winnowing?

A

A series of rising and falling notes.

139
Q

True or false? Scientists know the purposes of all flight feather modifications.

A

False.

140
Q

If a bird has an elongated rectrice, what is it likely used for?

A

Mating displays.

141
Q

What is an example of a flightless bird that seems to have mostly unmodifed flight feathers?

A

Three of the four species of steamer duck.

142
Q

What flightless water bird has reduced primaries?

A

The Titicaca grebe.

143
Q

What is the only ratite that still has its rectrices?

A

The ostrich.

144
Q

True or false? Penguins cannot fly because they have lost their differentiated flight feathers.

A

True.

145
Q

Why do feathers need to be moulted periodically?

A

When they finish growing, they often become dead structures and worn.

146
Q

What is the point where moulting begins called?

A

The focus.

147
Q

What is the focus for most passerine birds?

A

The innermost rectrices and primaries.

148
Q

Arctic birds moult very quickly compared to some southern birds. Why is this?

A

It allows them to complete their entire moult before migrating south.

149
Q

When a bird has multiple foci (plural of focus) along the wing, does the molt go in one direction?

A

Yes.

150
Q

Why do waterfowl drop all their flight feathers at once?

A

They have great difficulty flying when missing even a couple of their flight feathers, so a protracted molt would leave them vulnerable for a long time.

151
Q

How long are waterfowl vulnerable for after moulting?

A

Three or four weeks.

152
Q

Why do woodpeckers have a unique pattern of moulting where they drop their second innermost rectrices first?

A

It allows them to cover their growing feathers and maximize the amount of new feathers that are present when the crucial central retrices are lost.

153
Q

Do ground-feeding woodpeckers have the same molting pattern as tree-dwellers?

A

No.

154
Q

True or false? Adult and baby birds often have very similar remiges and rectrices.

A

False. They are substantially different.

155
Q

Why are juvenile feathers softer and of poorer quality than those of adults?

A

They all grow at once and the young bird simply does not have the energy to produce feathers similar to adults.

156
Q

What hapens when a bird or human repeatedly plucks the same feather?

A

The follicle becomes damaged and can no longer grow a feather.

157
Q

Describe how juvenile birds’ feathers are different from the feathers of an adult bird.

A

Juvenile feathers are narrower and more pointed at the tip. Also, the feathers of a juvenile will all be of the same length, since they all grew at the same time.

158
Q

True or false? The rectrices of most young raptors are longer than those of their adult counterparts.

A

True.

159
Q

What is the main theory as to why young birds have different feathers than the adults?

A

It compensates for their inexperience and weaker flying ability.

160
Q

what is a wing formula and what is it used for?

A

It describes the shape of a bird’s wing in a mathmatical way and is used to distinguish between species with similar plumages.

161
Q

Will birds that migrate a longer distance or shorter distance have longer primaries?

A

Long distance.

162
Q

In birds that change their plumage, what are the two kinds of plumages called?

A

Basic plumage and breeding plumage.

163
Q

What are the two most comon times that birds molt?

A

Before and after breeding.

164
Q

What is the scientific name for a species of bird that has more than one plumage?

A

A polymorph.

165
Q

Why is breeding plumage sometimes cryptic?

A

To better hide vulnerable birds that are sitting on the nest.

166
Q

What is the moult after the breeding season called?

A

The pre-basic moult.

167
Q

what is the moult prior to the breeding season called?

A

Pre-alternate moult.

168
Q

What is eclipse plumage?

A

Cryptic plumage that many ducks go into after breeding in mid summer.

169
Q

What is nupital plumage a synonym for?

A

Breeding plumage.

170
Q

Do birds of paradise keep their breeding plumage all year round?

A

Yes.

171
Q

What is the rate of albinism in birds?

A

1 in 1800

172
Q

What is partial albinism?

A

It is when local areas of an animal’s body is lacking the pigment melanin.

173
Q

Why are albino birds rare in the wild?

A

They are very conspicuous and have poor eyesight.

174
Q

why do male chickens sometimes gain female plumage?

A

They have a genetic condition in which their body produces large amounts of estrogen.

175
Q

What are some alternate causes for white feathers besides albinism?

A

Aging, nutrient deficiencies, circulatory problems, and defects in development.

176
Q

Why do some parrots appear green?

A

The feathers have yellow pigments, but reflect blue light.

177
Q

What are the three kinds of pigments in birds?

A

Melanins, carotenoids, and porphyrins.

178
Q

Are feathers stronger with or without melanin?

A

With melanin.

179
Q

How do birds acquire carotenoids?

A

They eat algae, plants, or other things that contain it.

180
Q

What non-irridescent color is odten the result of structural coloration in birds?

A

Blue.

181
Q

What kinds of structures are found in the barbules of blue birds?

A

Tiny air pockets.

182
Q

What are contour feathers?

A

The outermost feathers.

183
Q

When do birds shed powder down feathers?

A

They do not. Powder down feathers grow throughout their life and disintegrate when fully grown.

184
Q

What is the simplest kind of feather?

A

The filoplume.

185
Q

Describe a filoplume.

A

It is mostly a rachis, sometimes with a few small barbs on the end.

186
Q

What are semiplumes?

A

They are found between other feathers and allow for an additional layer of warmth.

187
Q

What is definitive plumage?

A

Full adult plumage.

188
Q

At what age do most songbirds reach their definitive plumage?

A

One year.

189
Q

What causes molting to occur?

A

Hormonal changes brought about by the change of seasons.

190
Q

Are damaged feathers replaced immediately? What about destroyed feathers?

A

No. Yes.

191
Q

What are the three patterns of molting?

A

One molt per year, one full molt and one partial molt, and two full molts.

192
Q

What kind of bone do both birds and dinosaurs have?

A

Wishbones.

193
Q

what were the three stages of evolution for feathers?

A

Wiry stalks, branched out stalks, intricate vanes.

194
Q

What is one of the main theories as to how flight evolved?

A

Feathers may have given dinosaurs an advantage by allowing them to move faster when running up steep inclines. This would have selected the dinosaurs that could escape better and caused dinosaurs to have longer arms and stronger feathers.

195
Q

Approximately how long did it take between when feathers first appeared to when birds began to fly?

A

50 million years.

196
Q
A