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Mammalogy > Exam 2 > Flashcards

Exam 2 Flashcards

1
Q

what is an amniote

A

egg with extraembryonic membranes and a shell

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2
Q

what are the 3 types of skull fenestration in amniotes

A

anapsid (no openings)
synapsid (1 opening)
diapsid (2 openings)

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3
Q

which type of skull fenestration characterizes mammals

A

synapsid

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4
Q

what are synapsids

A

pelycosaurs, mammals, therapsids, and cynodontia

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5
Q

what are some synapsid traits

A

-maxilla contacts quadratojugal bone
-single fenestra
-caniniform maxillary teeth
-post dentary bones modified for hearing

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6
Q

what are the 3 main groups of synapsids

A

pelycosaurs, therapsids, mammals

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7
Q

what are pelycosaurs

A

eothyrididae, caseidae, varanopeidae, sphenacodontidae

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8
Q

what are therapsids

A

biarmosuchia, dinocephalia, dicynodontia, gorgonopsia

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9
Q

what are some defining features of therapsids

A

-enlarged temporal opening
-sagittal crest and zygomatic arches
-upper canines enlarged
-feet shortened
-more upright limb posture

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10
Q

which group of therapsids are ancestral to mammals

A

cynodonts

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11
Q

what are some defining features of cynodonts

A

-dentary bone becomes major lower jaw element
-partial secondary palate
-zygomatic arches flare laterally
-teeth absent from pterygoid bone

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12
Q

what was the permian mass extinction

A

climate change due to large scale volcanism

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13
Q

what are some reasons why cynodonts survived the permian mass extinction

A

-small body size
-fast life history (grow quick, reproduce early)
-burrowers
-mammalian (heterodont teeth, large brain, warm blooded, fur)

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14
Q

what kinds of terrestrial vegetation characterized the mesozoic

A

ferns, cycads, ginkgophytes, bennettitaleans
conifers first appeared
early angiosperms appeared

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15
Q

what are some skeletal and inferred soft tissue features of early mesozoic mammals

A

skeletal:
-double rooted cheek teeth w/ premolars and molars
-diphyodont dentition
-mandibular symphysis reduced

soft tissue:
-mammary glands
-viviparity
-anal and urogenital openings

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16
Q

what are therian mammals

A

marsupials and eutherians

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17
Q

what are the anatomical traits of therian mammals

A

-tribosphenic molars
-protocone of the upper molar occludes with the talonid basin of the lower molar
-supraspinous fossa on scapula
-spiral cochlea

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18
Q

what is the evolution of a new dentary squamosal jaw joint

A

articular bone of lower jaw > malleus
quadrate bone of lower jaw > incus
angular bone of lower jaw > tympanic ring

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19
Q

what is the evolution of more complex molars

A

primary cusp, accessory cusp, cutting trigonid, crushing talonid

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20
Q

what is the evolution of the secondary palate

A

facilitated suckling

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21
Q

what is the evolution of parasagittal movement of limbs

A

sprawling vs erect

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22
Q

what is the evolutionary history of mesozoic mammalian radiations

A

-all continents except antarctica
-small bodied
-premolars/molars
-large brain
-lactation/suckling

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23
Q

what are the basic characteristics of haramiyidans

A

-earliest known herbivores
-teeth resemble multituberculates
-molars are parallel rows of cusps
-jaw moved with powerful backstroke

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24
Q

what are the basic characteristics of morganucodontids

A

-small, shrew like
-cheek teeth differentiated into premolars and molars
-premolars preceded by deciduous teeth
-chewing on one side of jaw at a time

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25
Q

what are the basic characteristics of docodonts

A

-highly derived roughly quadrate teeth, cusps not aligned anteroposteriorly

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26
Q

in what ways were haramiyidans, morganucodontids, and docodonts ecologically diverse

A

-docodonts swim and fish feed

-ambulatory carnivory or scavenging in large gobiconodontids

-scratch digging and feeding on colonial insects in fruitafossor

-climbing locomotion in basal eutherians and metatherians

-gliding adaptation in volaticotherium

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27
Q

australosphnidans are ancestral to which modern mammals

A

monotremes

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28
Q

what are the basic characteristics of eutriconodonts

A

unique molars

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29
Q

what are the basic characteristics of multituberculates

A

-herbivores or omnivores
-similar in appearance to rodents
-jaw movement similar to haramiyidans

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30
Q

define the clade boreosphenida

A

early mammals that originated in the northern hemisphere and has three cusped cheek teeth (metatherians and eutherians)

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31
Q

what is the significance of juramaia sinensis

A

earliest known marsupial

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32
Q

what is the significance of eomaia scansoria

A

earliest known placental mammal

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33
Q

what is the early rise hypothesis

A

ecological radiation of early mammals began prior to K-Pg boundary, driven by broadly coincident ecological radiations of flowering plants and some insect groups

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34
Q

what is the suppression hypothesis

A

mammals experienced ecological release following the end-Cretaceous mass extinction event at 66M

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35
Q

what is the delayed rise hypothesis

A

an ecological radiation occured in the eocene, possibly spurred by the paleocene-eocene thermal maximum at 56Ma

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36
Q

what is the basic climate of the epoch in the plaeocene

A

cretaceous subtropical

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37
Q

what is the importance of the site of corral bluffs, CO

A

K-Pg boundary

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38
Q

which paleocene mammals are considered ancestral to modern ungulates

A

condylarths

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39
Q

which paleocene mammals are considered ancestral to modern carnivores

A

miacids

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40
Q

which groups in the paleocene were the first to attain large body size

A

pantodonts and uintatheres

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41
Q

which modern groups of the paleocene are mesonychids and plesaidapiformes related to

A

artiodactyls

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42
Q

what is the basic climate of the epoch in the eocene

A

5-8 degree C global average temp rise, creatceous subtropical climate persisted

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43
Q

which group of ungulates has its peak of diversity in the eocene

A

perissodactyls

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44
Q

which modern group got its start in the eocene with the origin of the group archaeocetes

A

hippos

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45
Q

what are the 2 eocene groups of early primates

A

adapids (lemurs) and omomyids (tarsiers)

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46
Q

what is the basic climate of the oligocene

A

development of antarctic ice and changes in ocean circulation, brought about increased seasonality/overall cooling and drying

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47
Q

what was the grand coupure

A

eocene-oligocene climate driven extinction even

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48
Q

what is the significance of the paraceratherium

A

largest land mammal ever

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49
Q

which groups of primates originated during the eocene

A

aegyptopithecus and apidium

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50
Q

what is the basic climate of the epoch in the miocene

A

savannah woodlands dominate north america, semideserts, mountain building

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51
Q

which group of mammals had its peak of diversity in the miocene

A

proboscidean

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52
Q

which group of primates originated during the miocene

A

apes

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53
Q

what was the basic climate of the epoch in the pliocene

A

warming followed by continued global cooling, extensive glaciation

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54
Q

which south american group had its peak of diversity in the pliocene

A

ungulates

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55
Q

what was the great american biotic interchange

A

north america and south america attatched and northern mammals colonized a lot

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56
Q

which group of primates originated during the pliocene

A

hominids

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57
Q

what was the basic climate of the epoch during the pleistocene

A

periods of lowered temperatures alternated with periods of relative warmth, increased precipitation

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58
Q

what were the pleistocene megafauna

A

-saber tooth cats and imperial mammoths
-saber tooth cats and litoptern ungulates
-marsupial lions and short faced kangaroos

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59
Q

what is the evidence that supports the idea that humans caused the extinction of many pleistocene mammals

A

-archaeological evidence of co-occurrence and hunting
-non random extinctions
-immigrant species from asia less affected than native species
-dates of last known occurrence coincide with human migrations

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60
Q

what are basic mammalian trends

A

-endothermy/hair
-lactation
-sensory specializations
-heterodont dentition

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61
Q

what is the function of mammary glands in mammals

A

produce milk

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62
Q

what is the difference in milk delivery between monotremes and metatherians/eutherians

A

monotremes dont have external nipples

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63
Q

what is the function of sweat in mammals

A

promote evaporative cooling, eliminates some waste

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64
Q

what is the function of sebaceous in mammals

A

oily secretion that lubricates hair and skin

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65
Q

what is the function of scent and musk glands in mammals

A

attracts mates, marks territory, communication, protection

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66
Q

what is hair made of in mammals

A

keratin

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67
Q

what are the three layers of an individual hair in mammals

A

hair cuticle, cortex, medulla

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68
Q

countershading

A

upper body is darker than lower body

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69
Q

camouflage

A

hides an animal

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70
Q

disruptive coloration

A

strongly contrasting markings to break up the outline of an animal

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71
Q

warning coloration

A

warns predators

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72
Q

intraspecific communication

A

colors that mean something to another species

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73
Q

what is adipose tissue (fat) used for

A

-energy storage
-source of heat and water
-thermal insulation

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74
Q

where is fat often stored in mammals

A

tail or abdomen

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75
Q

what is the basic setup of the mammal circulatory system

A

systemic and pulmonary circuits
4 chambered heart

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76
Q

what is the basic setup of the mammal respiratory system

A

trachea > bronchi > bronchioles ? alveolar ducts > alveoli

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77
Q

what structures characterize the mammalian brain

A

-highly developed neocortex
-corpus callosum present

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78
Q

what characterizes the various mammalian sense organs

A

olfaction: receptors distributed across mucosal surfaces of mesethmoid and vomeronasal organ areas

hearing: high acuity, used in communication/orientation/food/enemies

sight: retina with photoreceptors

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79
Q

what 2 adaptations for fermentation are found in ungulates

A

foregut fermentation
hindgut fermentation

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80
Q

what are the characteristics of the mammalian skull

A

-akinetic
-zygomatic arch
-single crainomandibular jaw joint
-turbinal bones in nasal cavities
-foramina pass cranial nerves and vessels

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81
Q

what kinds of vertebrae are found in the mammalian axial skeleton

A

cervical
thoracic
lumbar
sacral
caudal

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82
Q

what are the 2 girdles for the limbs

A

pectoral and pelvic

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83
Q

what is the ancestral number of digits in the mammalian manus and pes

A

5

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84
Q

define crown

A

top of tooth

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85
Q

define root

A

portion of tooth underneath gum

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86
Q

define pulp cavity

A

inner tissue of tooth

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87
Q

define enamel

A

outer layer of tooth

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88
Q

define dentin

A

essential for support of the enamel layer

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89
Q

define cementum

A

outer layer of root

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90
Q

define rootless vs rooted teeth

A

rootless teeth continue growing (rodents)

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91
Q

what are the basic surface features of mammalian teeth

A

cusp - highest point of tooth
basin - lowest point of tooth

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92
Q

which bones produce teeth in mammals

A

dentary (lower jaw), premaxilla

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93
Q

define homodont

A

all teeth are the same shape

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94
Q

define heterodont

A

4 different tooth types

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95
Q

define diphyodont

A

two sets of teeth

96
Q

define polyphyodont

A

several sets of teeth

97
Q

what are some exceptions to the typical mammal pattern of teeth

A

-toothed whales
-manatees
-pinnipeds
-some rodents
-elephants
-kangaroos

98
Q

define dental placode (what cells make up this)

A

where a tooth starts (interaction between epidermis and dermis)

99
Q

define enamel knots

A

signals center to appear, marks the location sites of cusp formation

100
Q

define ameloblasts

A

cells that produce enamel

101
Q

define odontoblasts

A

produces dentin

102
Q

define periodontal ligament

A

ligament that holds tooth in socket

103
Q

what are the characteristics of tribosphenic upper and lower molars

A

upper - paracone and metacone on top, protoconule, metaconule, protocone on bottom

lower- protoconid and hypoconid on top, paraconid, hypoconulid, metaconid, entoconid on bottom

104
Q

how do tribosphenic upper and lower molars occlude

A

the upper molar fits inside of the lower molar

105
Q

what does the addition of hypocone have to do with tribosphenic upper and lower molars

A

cusp added to the primitively triangular upper molar teeth of therian mammals

106
Q

cone vs conid

A

cone - upper cusp
conid - lower cusp

107
Q

what is the function of the masseter muscle

A

close the jaw

108
Q

what is the function of the temporalis muscle

A

close the jaw

109
Q

what is the function of the medial pterygoid muscle

A

close the jaw

110
Q

what is the function of the lateral pterygoid muscle

A

open the jaw and pull jaw forward

111
Q

what is the function of the digastric muscle

A

raises tongue, opens jaw for chewing and speech

112
Q

what are the diet related differences in mastication

A

how they chew determines what they can eat

113
Q

dental formula?

A

goes from front to back, incisiors, canines, premolars, molars

114
Q

what are the primitive placental and marsupial dental formulas

A

marsupial: 5/4, 1/1, 3/3, 4/4
placental: 3/3, 1/1, 4/4, 3/3

115
Q

what are some edentulous mammals

A

-mysticete whales
-pangolins
-anteaters
-monotremes

116
Q

what are some variations in mammal incisor teeth

A

rodents: large and chisel like
lemurs: tooth comb
aye-ayes: rootless
elephants: tusks

117
Q

what are some variation in mammal canine teeth

A

modern carnivores: enlarged

118
Q

define brachydont

A

short crowned teeth

119
Q

define hypsodont

A

tall crowned teeth

120
Q

define bunodont

A

rounded cusps on molars

121
Q

define lophodont

A

cusps form ridges

122
Q

define selenodont

A

cusps form crescents

123
Q

define zalambdodont

A

v shaped crest

124
Q

define dilambdodont

A

w shaped ectoloph

125
Q

carnivory vs herbivory

A

carnivory: cheek teeth are blade like
vertical shearing

herbivory: cheek teeth become quadrate
jaw action became horizontal and transverse

126
Q

what hormone is produced by male testes

A

testosterone

127
Q

what are spermatogonia

A

sperm

128
Q

what is spermatogenesis

A

mitosis of sperm

129
Q

what are the differences in testes locations across mammals

A

abdominal:
-monotremes
-endentates
-elephants
-sirenians
-cetaceans

scrotum in:
most mammals

130
Q

what is a baculum

A

bone

131
Q

what are the greater number of functions required by females for reproduction

A

-make eggs
-receive and transport sperm
-gestate young
-birth/egg lay
-lactation
-parental care

132
Q

what are the basics of oogenesis

A

ova mature in paired ovaries, takes place in fetus during gestation

133
Q

what is the anatomy of the monotreme reproductive system

A

right and left uteri enter urogenital sinus, cloaca present

134
Q

what is the anatomy of the marsupial reproductive system

A

pair of uteri enter into vaginal sinus, duplex cervix, two vaginas

135
Q

what is the anatomy of the placental mammal reproductive system

A

retain paired ovaries, single vagina

136
Q

what are the four different kinds of placental mammal uteri

A

duplex
bipartite
bicornuate
simplex

137
Q

what are the ancestral characteristics of monotreme reproduction

A

-yolk with shell
-more yolk
-fetal egg tooth
-embryos at somite stage when laid

138
Q

what is the sequence of events in fertilization and early embryonic development in monotremes

A

fertilized in infundibulum > mucoid coating added > thin shell of ovokeratin added > second shell membrane added > uterine secretions aid embryogenesis > third shell layer added prior to birth

139
Q

what is the blastoderm

A

outer layer of egg

140
Q

how do marsupials and placentals differ in length of gestation and lactation

A

eutherians have longer gestation, shorter lactation

141
Q

define monoestrous

A

one estrous cycle per year

142
Q

define polyestrous

A

more than one estrous cycle per year

143
Q

4 phases of the estrous cycle

A

proestrus - development of endometrium and ovarian follicles

estrus - ovulation (luteinizing hormone LH)

metestrus - LH maintains corpus luteum, secretes hormones

diestrus - uterus is prepared for implantation

144
Q

which hormone is responsible for ovulation

A

LH (luteinizing hormone)

145
Q

what is the corpus luteum and what is its function

A

secretes hormones to prepare endometrium for implantation

146
Q

what is spontaneous ovulation

A

occurs without copulation, occurs widely among mammals

147
Q

compare and contrast the 3 types of marsupial estrous cycles

A

1: short gestation, no ovulation during lactation

2: gestation and estrous cycle length same, postpartum estrus and ovulation, embryonic diapause

3: same as 2 but w/ further development not controlled by lactation

148
Q

what is the sequence of events in fertilization and early embryonic development in marsupials

A

spontaneous ovulation > fertilization > cleavage divisions > mucoid layer > shell membrane > shell membrane becomes placenta

149
Q

what is the sequence of events in fertilization and early embryonic development in placental mammals

A

fertilization > cleavage divisions > blastocyst reaches uterus > outer layer adheres and erodes > forms placenta > forms embryo

150
Q

what is the protoderm

A

a unique developmental layer in marsupials

151
Q

what are the inner cell mass and trophoblast

A

inner cell mass forms embryo
trophoblast forms placenta

152
Q

what is the chorioviteline placenta

A

highly vascularized portion of yolk sac

153
Q

what is the chorioallantoic placenta

A

highly vascularized chorioallantoic membrane

154
Q

describe the macropodidae placenta

A

choriovitelline

155
Q

describe the peramelemorphia placenta

A

choriovitelline and chorioallantoic

156
Q

describe the placental mammal placenta

A

chorioallantoic

157
Q

define epitheliochorial placenta (which mammals have this?)

A

oxygen and nutrients pass through walls of uterine blood vessels and through layers of connective tissue and epithelium

-lemurs, some ungulates, cetaceans

158
Q

define endotheliochorial placenta (which mammals have this?)

A

epithelium of the chorion is in contact with endothelial lining of uterine capillaries

-carnivorans

159
Q

define the hemochorial placenta (which mammals have this?)

A

endothelial lining of the blood vessels in villi separate fetal blood from surrounding maternal blood sinuses

-insectivorans, rabbits, bats, higher primates, rodents

160
Q

define the diffuse shape of eutherian placenta (which mammals have this?)

A

villi occur over large surface area

-lemurs, artiodactyla, perissodactyla

161
Q

define the cotyledonary shape of eutherian placenta (which mammals have this?)

A

villi in regularly spaced clusters

-ruminant artiodactyla

162
Q

define the zonary shape of eutherian placenta (which mammals have this?)

A

band of villi encircles chorion

-carnivorans

163
Q

define the discoidal shape of eutherian placenta (which mammals have this?)

A

villi in disk shaped zone

-insectivorians, bats, primates, rodents, rabbits

164
Q

what are the hormonal pathways involved in metatherian parturition

A

corpus luteum

165
Q

which hormones trigger uterine contractions in metatherians

A

mesotocin

166
Q

how does the fetus get into the pouch and what happens once it is in there

A

crawls into pouch, attaches to bud at tip of teat

167
Q

what are the hormonal pathways involved in eutherian parturition

A

estrogen and lowering of progesterone

168
Q

which hormones trigger uterine contractions in eutherians

A

estrogen

169
Q

what is the difference between a deciduous or nondeciduous placenta

A

non: villi pull out of uterine pits

deciduous: placenta is torn away at birth

170
Q

which hormones promote mammary gland development

A

estrogen, progesterone, insulin, placental lactogen

171
Q

which hormone regulates lactation

A

prolactin

172
Q

what are the three stages of metatherian lactation

A

mammogenesis: prep
early lactogenesis: young attach to teat
late lactogenesis: young are detatched

173
Q

how do metatherians and eutherians differ in milk composition across the lactation period

A

eutherians: uniform
marsupials: varies

174
Q

how do metatherians and eutherians differ in milk composition across species

A

marsupials: varies little
eutherians: varies lot

175
Q

which requires more energy: pregnancy or lactation

A

lactation

176
Q

what are the various costs of reproduction on female mammals

A

-increase food intake
-decrease activity
-metabolize fat
-shift diet
-anatomical changes

177
Q

what is the foraging cycle strategy (and in which pinnipeds is this found?)

A

females forage at sea but return to nurse

-sea lions, fur seals

178
Q

what is aquatic nursing strategy (and in which pinnipeds is this found?)

A

suckling at sea

-walrus

179
Q

what is the fasting cycle strategy (and in which pinnipeds is this found?)

A

females rely on blubber and fast during lactation

-seals

180
Q

what is the combination of fasting and foraging strategy (and in which pinnipeds is this found?)

A

fast sometimes, forage sometimes

-seals

181
Q

what are the details of delayed fertilization and in which mammals does it occur

A

mate and store sperm in fall, fertilize in spring

-rhinolophid and vespertilionid bats

182
Q

what are the details of delayed implantation and in which mammals is it found

A

development paused at blastocyst stage

-metatherians, carnivora, chiroptera, pilosa, artiodactyla

183
Q

what is the difference between obligate and facultative delayed implantation

A

obligate: consistent part of reproductive cycle
facultative: occasions when animal is nursing large litter

184
Q

what are the details of delayed development and in which mammals does it occur

A

blastocysts stops growing until newborn leaves pouch

-kangaroo

185
Q

how does photoperiod affect the timing of reproduction

A

day > night

186
Q

what is the effect of melatonin on reproduction

A

day > night

187
Q

what is the effect of temperature on reproduction

A

warmer > colder

188
Q

what is the effect of energy/nutrition on reproduction

A

plant secondary compounds and phyoestrogens

189
Q

how do plant secondary compounds and phytoestrogens play a role in reproduction

A

PSC: chemicals that trigger reproductive behavior

phyto: plant compounds that mimic animal estrogens

190
Q

how do behavioral controls influence reproduction

A

pheremones produced attract mates, signal receptivity

191
Q

what is the bruce effect and in what mammals is this seen

A

unfamiliar male in habitat, females reenter estrus more quickly

192
Q

why is it advantageous for a new male in a group to commit infanticide

A

male brings females into estrus more quickly

193
Q

what are the characteristics of the altricial young strategy

A

-helpless at birth
-nearly naked
-ears/eyes closed
-cannot locomote or thermoregulate

194
Q

how does the semelparity strategy affect males

A

death, males lose significant body weight and fur

195
Q

what are the characteristics of the precocial young strategy

A

fur
eyes and ears functional
locomote and thermoregulate

196
Q

what is the general rule relating gestation length and body size in mammals

A

positive correlation

197
Q

what are some exceptions to the body size/gestation length rule in mammals

A

elephant shrews, sloths, baleen whales, primates

198
Q

why is inbreeding avoidance important

A

mortality, susceptible to disease, genetic issues

199
Q

what are some ways inbreeding is avoided

A

dispersal from natal area, kin recognition

200
Q

how does environment influence the timing of reproduction

A

good season > more breeding

201
Q

in what way does reproductive effort vary with residual reproductive value

A

varies inversely

202
Q

define endothermy

A

internal heat production

203
Q

define homeothermy

A

constant heat production

204
Q

how are ectotherms different than endotherms

A

ecto- heat gained from environment

endo- heat produced

205
Q

what are the advantages and disadvantages of being ectothermic

A

advantages:
-no high basal metabolic rate
-endure shortages of food/water/O2
-elongate shape or tiny

disadvantages:
-rapid exhaustion
-brief activity

206
Q

what are the advantages and disadvantages of being endothermic

A

advantages:
-high work capacity

disadvantages:
-lots of food, water, O2

207
Q

define regional heterothermy

A

core body temp is maintained well above that of other body regions

208
Q

define temporal heterothermy

A

mammals modify their body temp in response to fluctuations daily seasonal environmental temp

209
Q

how do core body temperatures vary within mammal groups

A

core body temp is constant but body temp varies

210
Q

how do core body temperatures vary between metatherians and eutherians

A

metatherians - lower body temp
eutherians - higher body temp

211
Q

what is the thermoneutral zone

A

zone in which little or no metabolic energy is expended on temp regulation

212
Q

what does a mammal need to do if its body temp fluctuates below the lower critical temperature

A

additional heat production

213
Q

what does a mammal need to do if its body temp fluctuates above the critical temperature

A

additional heat dissipation

214
Q

how does food quality affect metabolic rates

A

better food quality = higher metabolic rates

215
Q

4 strategies to dealing with cold

A

1) large body size
2) decrease rate of heat loss
3) increase metabolic heat production
4) abandon normal body temp

216
Q

what does bergmann’s rule describe

A

boreal mammals larger than tropical counterparts

217
Q

what is the relationship between surface area and volume

A

surface area increases with square of linear dimension

volume increases with cube of linear dimension

218
Q

what kinds of mammals have trouble staying cool

A

large

219
Q

what kinds of mammals have trouble staying warm

A

small

220
Q

what is the relationship between body size and a mammal’s lower critical temperature

A

small: lower critical temp
large: higher critical temp

221
Q

what is the difference between the basal metabolic rate and the field metabolic rate

A

basal- measured under controlled lab conditions

field - free living animals eating, digesting, moving

222
Q

how does the mass specific metabolic rate vary with body size

A

smaller mammals have higher metabolisms

223
Q

how does the absolute metabolic rate vary with body size

A

larger mammals have higher metabolisms

224
Q

what kinds of insulation do mammals have

A

blubber

225
Q

how can water decrease the usefulness of insulation

A

fur gets compressed when wet and doesn’t insulate anymore

226
Q

how does vasoconstriction promote regional heterothermia

A

decreases blood flow to skin

227
Q

how do countercurrent heat exchange systems decrease heat loss

A

cool blood warmed by arterial blood as it returns to core

228
Q

how does shivering counteract heat loss

A

heat production by cold induced involuntary muscle contraction

229
Q

what is the purpose of daily torpor

A

body temp, metabolic rate, respiration, and heat rate are lowered

230
Q

what is seasonal torpor triggered by

A

food deprivation, short day length, low temps in environment

231
Q

what are the 3 phases of seasonal torpor

A

rapid entry, prolonged period, rapid arousal

232
Q

how do shallow hibernation and profound hibernation differ

A

shallow: hibernation for a short period
profound: hibernation for a long period

233
Q

what are the 2 types of arousal

A

alarm- ambient temp drops beyond animal’s ability to compensate

periodic- absence of external cues

234
Q

how does non shivering thermogenesis work

A

metabolic heat produced by metabolizing fat

235
Q

what are some temperature regulation methods used by bats

A

heterothermy, hibernation

236
Q

what are other ways mammals deal with cold environments

A

migration

237
Q

what is behavioral thermoregulation

A

using the environment to warm up or cool down

Mammalogy (3 decks)

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