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Vertebrate Zoology > Exam 4 > Flashcards

Exam 4 Flashcards

1
Q

What class are birds in?

A

Aves

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2
Q

How many species of birds are there?

A

10,000

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3
Q

What are birds hypothesized to be very closely related to?

A

theropod dinosaurs

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4
Q

What theropod in particular is closely related to birds?

A

velociraptor

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5
Q

Why are birds thought to be so closely related to theropods?

A

have many skeletal characteristics in common with some theropods

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6
Q

Based on cladistics birds may have actually represented what?

A

a living dinosaur which is specialized for flight

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7
Q

Where are the earliest fossil birds from the Jurassic sediment from?

A

Germany

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8
Q

What is considered to be the first bird in the fossil record?

A

archaeopteryx

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9
Q

What does archaeopteryx mean?

A

ancient wing

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10
Q

What is a bird with many reptile characteristics?

A

archaeopteryx

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11
Q

What are some characteristics of archaeopteryx?

A

feathers
reptile head with teeth and scales
well developed tail vertebrae

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12
Q

What did archaeopteryx have that modern birds do not?

A

well developed tail with vertebrae

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13
Q

Why is it thought that archaeopteryx could only fly for short distances?

A

appeared to be relatively heavy

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14
Q

When did birds try to challenge the mammals for dominating the terrestrial environment?

A

during the tertiary period (early in Cenozoic)

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15
Q

What is gastornis also known as?

A

diatryma

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16
Q

What is diatryma/gastornis?

A

large carnivorous flightless bird

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17
Q

How big did diatryma/gastornis get?

A

7 ft in height

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18
Q

What are some physical characteristics of diatryma/gastornis?

A

fast runner
large legs and head
short wings

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19
Q

What kind of beak did diatryma have and what was it used for?

A

large hooked beak for killing prey and tearing meat

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20
Q

How big was the terror bird?

A

7 ft in height

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21
Q

When did terror bird occur?

A

about 2 million years ago

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22
Q

Where was terror bird found?

A

not America from central FL to TX

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23
Q

How are birds skeletal systems adapted for flight?

A

it is light but sturdy

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24
Q

Birds have pneumatic bones, what are they?

A

air filled cavities for the larger bones

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25
Q

What bones in birds are pneumatic?

A

wings and legs

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26
Q

Why are many bones in birds fused together? what is an example of a bone like that?

A

for strength; skull

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27
Q

How much does the skeleton of a 20 lb pelican weigh?

A

only 23 ounces

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28
Q

What does the trunk portion of a birds skeleton do?

A

forms a rigid airframe

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29
Q

What other bones besides the skull are fused together in birds?

A

vertebrae
ribs to sternum & vertebrae

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30
Q

What are present in between ribs in birds?

A

braces known as uncinate processes

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31
Q

Is a large keeled sternum found in all birds?

A

no, just most

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32
Q

What does a keel do?

A

facilitates the attachment of flying muscles

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33
Q

What are ratites?

A

group of flightless birds that rely on running (no keel)

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34
Q

What are birds are ratites?

A

ostrich, rhea, cassowary

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35
Q

What does the rigid trunk provide in birds?

A

strong structure for attachment of wings and wing muscles

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36
Q

What is the synsacrum?

A

composed of sacral, lumbar, and caudal vertebrae fused with bones of pelvic girdle

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37
Q

What does the synsacrum provide for birds?

A

solid platform for attachment of the legs

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38
Q

What are toes adapted for in birds?

A

the birds ecology

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39
Q

How many toes do birds usually have?

A

4 (mostly), 3 forward and 1 back

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40
Q

What is the roadrunner’s arrangement of toes like and what is it used for?

A

2 forward 2 back, facilitate running

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41
Q

What are toes and feet specialized for in many birds?

A

perching and/or capturing prey

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42
Q

How does perching work in a bird?

A

as a bird bends its legs on a branch, the tendons automatically tighten toes grip on the branch

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43
Q

Why are feathers homologous to reptile scales?

A

develop in similar ways, epidermal in origin

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44
Q

What do feathers appear to be?

A

slightly modified reptile scales

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45
Q

What would feathers be used for in the dinosaurs that did have them?

A

used of insulation rather than flight

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46
Q

What is the feather vane composed of?

A

bards with small hooks called barbules

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47
Q

What are feathers composed of?

A

protein keratin

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48
Q

What are contour feathers used for?

A

provide streamlined profile of body to enhance flight

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49
Q

What are flight feathers used for?

A

give shape to the wings and tail and provide lift

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50
Q

What are down feathers used for?

A

insulation

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51
Q

Where are down feathers located?

A

under the contour feathers

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52
Q

How do down feathers insulate?

A

the loose structure traps air

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53
Q

Describe penguins.

A

have more feathers than another bird due to cold climate

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54
Q

How many feathers can penguins have?

A

up to 70 per square inch

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55
Q

How do feathers help with buoyancy?

A

trap air to increase buoyancy

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56
Q

What other functions of feathers have?

A

camo
advertisement for mating and territoriality

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57
Q

What are special ornate feathers called?

A

filiplumes

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58
Q

Where do birds have scales?

A

on feet and legs (epidermal scales)

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59
Q

Are birds endotherms or exotherms?

A

endotherms

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60
Q

What is the body temp of birds?

A

40-41 celcius

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61
Q

What animal is the warmest vertebrate?

A

birds

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62
Q

Endothermy and flight require increased amounts of energy, so what systems have to have a decreased amount of energy?

A

circulatory and respiratory

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63
Q

What kind of heart do birds have?

A

4 chambered

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64
Q

Why is a birds respiratory system so efficient?

A

to sustain the energy requirements of flight and homeothermy

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65
Q

How do birds breathe with no diaphragm?

A

movement of ribs, sternum, and wings move air through lungs

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66
Q

How many air sacs do birds have and where are they?

A

about 9; in thorax and abdomen that attach to lungs

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67
Q

What do air sacs do?

A

enhance the unidirectional flow of air through lungs

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68
Q

What do air sacs decrease?

A

“rebreathing” of old air as in mammals and allows for efficiency

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69
Q

Do birds sweat?

A

no

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70
Q

How do birds keep cool if they don’t sweat?

A

air sacs help cool the bird

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71
Q

How do air sacs function in brown pelicans?

A

they also act as shock absorbers for diving birds

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72
Q

Where are birds larynx’s located?

A

top of the trachea

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73
Q

Is the larynx the sound producing organ in birds?

A

no

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74
Q

What does the larynx do?

A

modulates sound produces by the syrinx

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75
Q

Where is the syrinx located?

A

lower end of trachea where bronchi meets trachea

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76
Q

What is the syrinx responsible for?

A

sound producing, wide variations of sounds made by birds

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77
Q

Why is sound important in most birds?

A

used for reproduction and social functions

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78
Q

What is bird song used for?

A

advertise for mates and for territoriality

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79
Q

Describe bird songs.

A

composed of long, complex sounds
used by males
stimulated by testosterone
only during breeding season

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80
Q

What are birds sounds?

A

shorter sounds used as alarm calls or contact calls between birds

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81
Q

What is an example of how bird calls are used?

A

birds flying in flock will produce calls to indicate their location

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82
Q

Are bird calls produced by both males and females?

A

yes

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83
Q

What is the difference between the bird brain and the reptile brain?

A

everything is the same except birds have larger cerebrum and cerebellum

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84
Q

What is different when you compare bird and mammal brains?

A

birds cerebral cortex is thin and poorly developed in comparison to mammals

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85
Q

What is neocortex and do birds have it?

A

type of cortical tissue found in mammalian brain; no

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86
Q

What is the core of the cerebrum important for in birds?

A

helping control basic activities like eating, singing, flying, and reproductive behaviors

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87
Q

What is the large cerebellum important for in birds?

A

coordinating flight

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88
Q

What are the large optic lobes in birds used for?

A

birds have very good vision

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89
Q

How many pairs of cranial nerves do birds have?

A

12

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90
Q

What is the specialized structure in bird eyes and what does it do?

A

pecten; highly vascularized and enhances blood flow to retina while not obscuring vision with blood vessels

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91
Q

Describe hawk vision.

A

8 times better than humans due to high density of cone cells

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92
Q

How are hawk eyes different from human eyes?

A

hawks eyes are oblong compared to humans so images are spread over a larger area of retina

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93
Q

How do owl eyes compare to humans?

A

up to 100 times more sensitive to light due to higher density of rods

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94
Q

Why do some birds have 2 fovea per eye?

A

one for forward vision (pursuing prey)
one for lateral vision (scanning for prey)

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95
Q

Where is the fovea located in birds?

A

primary focus on the retina

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96
Q

How do birds accommodate their eyes?

A

by changing shape of lens

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97
Q

Why do birds have good hearing?

A

mate recognition
communication
detecting predators

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98
Q

What do birds have that cover their ear holes and outer ear canals?

A

feathers

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99
Q

Describe a birds ear.

A

tympanic membrane and single middle ear bone (columella) that connects to the cochlea

100
Q

Do birds have nostrils, if so where are they located?

A

opening to nostrils on upper beak near the start of the beak

101
Q

Do birds have larger or smaller olfactory bulbs in comparison to reptiles?

A

smaller

102
Q

What birds have good senses of smell?

A

vultures
many ground dwelling birds
kiwis

103
Q

What is a kiwi? Describe it.

A

nocturnal flightless bird from New Zealand; its nostrils are on the top of bill, probes soil with long beak and smells for food

104
Q

What does a kiwi typically eat?

A

earthworms

105
Q

What is the reproduction strategy of all birds?

A

oviparous

106
Q

Why would developing young in the body not be advantageous for birds?

A

developing young in body would weigh too much, difficult for the mother to fly

107
Q

What parts of the reproductive system only develop in most species of birds (females) and why?

A

only left ovary and oviduct develop; helps reduce weight

108
Q

How does the ovary ovulate in birds?

A

ovulates yolk and ovum, which is fertilized near the top of the oviduct

109
Q

Describe the oviduct in birds.

A

well developed and deposits albumin and eggshell

110
Q

Does egg size and color vary by species?

A

yes it does

111
Q

What develops reproductively in a male bird?

A

both testes
some have penis

112
Q

How is sperm transferred within birds?

A

simply bringing the cloaca in contract

113
Q

What does flight allow some birds to do?

A

long distance movements between spring and summer breeding ground and winter feeding grounds

114
Q

What does long distance travel flying also allow birds to do?

A

maximize day length for the entire year which can enhance feeding

115
Q

Why fly north to breed during spring/summer?

A

northern breeding areas have less predators, and seasonally larger numbers of insects to feed young; longer day lengths more feeding time

116
Q

What do kidneys in some birds have and what do they do?

A

well developed loops of henle; help concentrate urine

117
Q

What is the molarity of typical body fluid in birds? What is the molarity of birds urine?

A

300 mOsm; 2000 mOsm

118
Q

What animals can produce concentrated urine?

A

only mammals and some birds

119
Q

What is the major waste product in the urine of birds?

A

uric acid

120
Q

What is guano?

A

formed when urine and feces mix in the cloaca

121
Q

What is a major component of guano?

A

urea

122
Q

Why is guano from birds mined from islands it accumulates on?

A

it is rich in nitrogen and phosphates

123
Q

Where is the salt gland in most seabirds?

A

above the eye

124
Q

What does the salt gland in most sea birds do?

A

produces concentrated salt solution up to 1880 mOsm, helps birds get rid of excess salt

125
Q

Why wouldn’t it be advantageous for birds to bear live young?

A

would make the mother be too heavy to fly

126
Q

How many living species are there in class mammalia?

A

5450

127
Q

What are mammals structurally related to ?

A

therapsid reptiles

128
Q

When do the first mammals appear in the fossil record?

A

triassic

129
Q

What are the first mammals to appear?

A

small insectivores

130
Q

Mammals stay small throughout what era?

A

mesozoic era

131
Q

When do mammals radiate?

A

territory period in Cenozoic era

132
Q

When do mammals become the dominant vertebrae?

A

cenozoic era

133
Q

Why is mammal skin more advanced than that of reptiles?

A

evolved to both protective and performs a variety of functions

134
Q

What does the epidermis and dermis do?

A

provides tough out layer of the body for protection and waterproofing

135
Q

What is hair important for in mammals?

A

insulation
coloration
tactil sensations
protections

136
Q

Why is hair better than feathers for mammals?

A

better insulator and less bulky than feathers
gives lower profile
allows for endothermy

137
Q

How does hair help with coloration?

A

camoflauge and display

138
Q

How is hair used for tactile sensations?

A

whiskers or “vibrissae”

139
Q

What is an example of how hair modified for protection?

A

porcupine
spiny anteater

140
Q

What are other structures that extend from the skin?

A

true horns
antlers
rhinoceros horn

141
Q

Where are true horns found in mammals?

A

family bovidae “ruminants”

142
Q

What are true horns used for?

A

defense and fighting between males, possibly for mate ID and attraction

143
Q

What are true horns made from?

A

sheathes of cornfield epithelium (keratin) that surrounds inner bony layer

144
Q

Are true horns normally shed?

A

no, although some sheep periodically shed outer cornified layers

145
Q

Are true horns typically found on both males and females?

A

typically on males, often found on both sexes

146
Q

What family are antlers normally found?

A

family cervidae (deer family)

147
Q

Are antlers found on males or females?

A

only males

148
Q

What are antlers used for?

A

defense and fighting between males and important in attracting females

149
Q

Describe antlers.

A

composed of bone with vascularized skin “velvet”
highly branched

150
Q

Do the size of antlers increase with age?

A

yes

151
Q

Do antlers shed?

A

yes, complete set is grown and shed each year

152
Q

When are antlers typically grown?

A

grown in summer and mating occurs in the fall

153
Q

What is growth and shedding controlled by?

A

hormones (testosterone)

154
Q

What is shed on antlers before mating season?

A

skin on antlers

155
Q

When and why are antlers shed?

A

shed after mating season after testosterone levels decrease

156
Q

What are rhino horns composed of?

A

dermal hair like fibers which adhere together to form a single horn

157
Q

Do both sexes of rhinos have horns and are they shed?

A

yes and no they don’t shed

158
Q

What are sweat glands used for in mammals?

A

help regulate body temp through evaporative heat loss

159
Q

What are sebaceous glands used for?

A

hair follicle; help produce sebum (oil) which lubricates skin and hair

160
Q

What are scent glands also known as?

A

apocrine glands

161
Q

What do scent glands contain and why?

A

pheromones; mate recognition and attraction, territoriality

162
Q

Scent is an important form of what in mammals?

A

communication

163
Q

What is an example of scent being used for defense?

A

skunk anal scent glands; raise tail and spray potential predators

164
Q

How far can skunks spray?

A

10-15 ft

165
Q

Humans have scent glands associate with some hair follicles in what areas?

A

axial areas (armpits)

166
Q

What have human scent glands produced?

A

lucrative deodorant industry as well as perfume and cologne industry

167
Q

What are mammary glands used for?

A

nourishing young by producing and secreting milk

168
Q

What kind of control are mammary gland under?

A

hormone

169
Q

What is the function of estrogen and progesterone?

A

stimulate growth of mammary glands

170
Q

What is the function of prolactin?

A

stimulated production of milk

171
Q

What is the function of oxytocin in mammary glands?

A

stimulates ejection of milk

172
Q

What do mammary glands allow for in mammals?

A

feed offspring regardless of food availability in environment

173
Q

Mammals have a high or low metabolic rate in comparison to ectotherms?

A

high metabolic rate (atleast 10 times greater)

174
Q

What does homeothermy allow for in mammals?

A

prolonged periods of high activity including nocturnal
exploit a wide range of habitats (cold regions)

175
Q

What is the temp among monotremes?

A

28-30 C

176
Q

What is the temp among marsupials?

A

33-36 C

177
Q

What is the temp among placentals?

A

36-38

178
Q

Why is mammalian CNS the most highly developed of vertebrates?

A

have largest and most highly developed cerebral cortex of any vertebrates
convolutions on cortex surface
higher level nervous functions

179
Q

Mammals also have the most highly developed what of vertebrates and what does it allow for?

A

cerebellum; allows for more complex movements

180
Q

How many cranial nerves do mammals have?

A

12

181
Q

Are mammals the only vertebrate to thoroughly chew food?

A

yes

182
Q

Mammals typically have what kind of teeth?

A

heterodont teeth

183
Q

What are heterodont teeth?

A

different types of teeth specialized for certain functions

184
Q

Teeth reflect what of the animal?

A

diet of animal

185
Q

What kind of teeth do reptiles have?

A

homodont teeth

186
Q

Do mammals continually replace their teeth during life? How many sets do mammals get?

A

no; 2 sets, primary and permanent

187
Q

What kind of tooth diversity do elephants show?

A

tusks that are highly developed incisors

188
Q

What kind of tooth diversity of walrus have?

A

tusks that are canines

189
Q

What kind of tooth diversity do wild boars have?

A

tusks that are canines

190
Q

What kind of tooth diversity of vampire bats have?

A

fangs that are incisors

191
Q

What kind of tooth diversity do narwal cetaceans have?

A

males tusk are incisors

192
Q

How are herbivores digestive systems specialized?

A

long intestines needed for digesting plants, some have chambered stomachs (ruminants)

193
Q

How are carnivores digestive systems specialized?

A

shorter intestines

194
Q

Do all mammals have loops of henle?

A

yes

195
Q

What is the molarity of desert mammals urine?

A

up to 9000 mOsm

196
Q

What kind of heart do mammals have?

A

4 chambered

197
Q

Why do mammals have well developed muscular diaphragms?

A

for efficient ventilation while breathing

198
Q

Are mammals the only vertebrates that use a diaphragm for breathing?

A

yes

199
Q

What are the 3 basic groups of mammals?

A

monotremes
marsupials
placentals

200
Q

What order are monotremes and how many species are there?

A

monotremata; 3 species

201
Q

What order are marsupials in an how many species are there?

A

marsupialia; about 360 species

202
Q

What infraclass are placentals in and how many species are there?

A

eutheria; 5000 species

203
Q

What does the word monotreme refer to?

A

one opening, referring to the cloaca

204
Q

Are monotremes the only mammals with a cloaca?

A

yes

205
Q

Where are monotremes restricted to?

A

Australia, Tasmania, and New Guinea

206
Q

Why are monotremes restricted to specific places?

A

isolated for 65 million years, since the breakup of Gondwana at the end of the mesozoic

207
Q

What did isolation do for monotremes?

A

prevented them form being out competed by placental mammals

208
Q

What is the most primitive of all living mammals?

A

monotremes

209
Q

What are examples of primitive characteristics in monotremes?

A

lay eggs
have a cloaca

210
Q

What are the 3 living species of monotremes?

A

2 species of echidna
duck billed platypus

211
Q

What is an example of an echidna?

A

spiny anteaters

212
Q

How big are adult platypus and echidna?

A

small to medium sized (2-10 kg)

213
Q

What are monotremes?

A

egg laying mammals

214
Q

How many eggs do monotremes normally lay?

A

one to two eggs

215
Q

Where do the eggs travel in a monotreme?

A

egg travels down oviduct and into cloaca before being laid

216
Q

How long does it take a monotreme to hatch an egg after incubation?

A

10-12 days

217
Q

Are monotreme young more mature or relatively young when born?

A

relatively young

218
Q

How long do monotreme young feed on milk from the mammary glands?

A

up to 5 months

219
Q

Is egg laying an efficient form of reproduction?

A

no not compared to placental mammals

220
Q

What are example of marsupial animals?

A

kangaroo
opossum

221
Q

Where do marsupials predominate?

A

Australia, New Guinea, and Tasmania

222
Q

Are marsupials isolated for the same reason as monotremes?

A

yes

223
Q

What are the only placental mammals indigenous to Australia?

A

bats

224
Q

Do marsupials also occur in South, Central, and North America?

A

yes

225
Q

What is the only marsupial in North America and where did it migrate from?

A

opossum; migrated from South America

226
Q

What does a marsupial embryo receive nutrition from?

A

uterine secretion

227
Q

What forms in marsupials for a brief time prior to birth?

A

a primitive placenta

228
Q

When are marsupial young usually born?

A

10-30 days after development depending on the species

229
Q

Where do marsupial young go after birth?

A

move to pouch without help from mother, attach to nipple for nourishment

230
Q

How long is the lactation period and parental care in marsupials?

A

several hundred days
235 days in kangaroos

231
Q

What are the various stages marsupial young go through for development?

A

pouch
out of pouch but nursing
one in uterus

232
Q

What is embryonic diapause?

A

when another embryo is developing in the uterus, at this time it development of embryo is temporarily halted until young leaves pouch

233
Q

What is hypothesized to have happened to marsupials and placentals and why?

A

convergent evolution; fill the same niches and have similar body forms

234
Q

What is convergent evolution?

A

environment is selecting for the same traits in two different groups of mammals

235
Q

Where does the development of placental mammals occur?

A

in uterus with the support of the placenta

236
Q

When was the first placental fossil found?

A

during the tertiary period

237
Q

Are monotremes and marsupials found earlier or later than that of placentals in the fossil record?

A

earlier

238
Q

What is the placenta?

A

an interface between maternal and embryonic blood, blood doesn’t actually move across placenta between mother and embryo

239
Q

What does the placenta allow for?

A

exchange of gases, nutrients, and waste

240
Q

What does the placenta shield the embryo from?

A

the maternal immune system

241
Q

What kind of organ is the placenta and what does it produce?

A

endocrine organ; produces hormones that help maintain uterine condition

242
Q

Do placental mammals have an efficient means of producing young?

A

yes

243
Q

Is the total time for gestation and lactation for placentals shorter than that of marsupials?

A

yes

244
Q

What gives eutherians a distinct advantage over marsupials and monotremes?

A

shorter time to produce offspring

245
Q

How many orders of mammals are there?

A

about 30

246
Q

What are the majority of the orders for in mammals?

A

placental mammals

Vertebrate Zoology (4 decks)

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