Final Flashcards
1
Q
Four aspects of life that mammals need energy and nutrients to maintain
A
- Growth
- Activity
- Reproduction
- Survival
2
Q
Describe the digestive tract of insectivores
A
- Ingest minimal fibre so alimentary canal is short
- Typically lack a cecum
3
Q
Describe the digestive tract of carnivores
A
- Short intestine and colon
- Small or no cecum (may be replaced by appendix)
4
Q
Describe the digestive tract of non-ruminant herbivores
A
- Simple stomach, large cecum
5
Q
Describe the digestive tract of ruminant herbivores
A
- Four-chambered stomach
- Large rumen
- Long small and large intestine
6
Q
Which nerve, that coordinates swallowing and respiration, is designed imperfectly?
A
- The laryngeal nerve (a branch of the vagus nerve)
7
Q
What is a guild?
A
- A group of species having similar ecological resource requirements and foraging strategies, and therefore having similar roles in community
8
Q
Based on what characteristics can echolocating bats be divided into guilds?
A
- Preferred habitat
- Foraging behaviour
- Distinct adaptations to wing morphology
- Structure of echolocation signals
9
Q
Difference between fundamental and realized niche?
A
- Fundamental = Niche that is free from interference
- Realized = Niche that is narrower and involves interactions with other species
10
Q
What does myrmecophagous mean? What traits to these mammals typically have?
A
- Myrmecophagous: Feeding primarily on colonial insects such as ants and termites
- Characteristics: Reduction of teeth (or teeth peg-like if present), long and extendible tongues, elongated snouts, strong front feet, large claws, and enlarged salivary glands
11
Q
Describe tusks in walrus and their functions
A
- Tusks are enlarged canines that lack enamel
- Used in aggressive encounters, establishing dominance hierarchies, feeding, locomotion, breaking through ice
12
Q
Difference between dugong and manatee diet?
A
- Dugongs eat aquatic vegetation that is much softer than that consumed by manatees
- Have more peg-like dentition than manatees
- Manatees eat water hyacinth, mangrove leaves, etc.
13
Q
What is the Eimer’s organ?
A
- Sensitive tactile organ on the snout of moles and desmans
14
Q
What can the cortex in the brain tell you about the importance of different body parts in mammals?
A
- The amount of brain cortex devoted to processing information from a certain body part can reflect its importance for the animal
15
Q
What pairs of teeth are for crushing bones in the bone crushing wolf and spotted hyaena? What does this free up for cutting meat?
A
- Bone crushing wolf (extinct) = P4/P4
- Spotted hyaena = P3/P3 (access fat in long bones)
- Frees up carnassial pair (P4/M1) for carnassial and cutting meat
16
Q
What do differences in mandibular force profiles reflect in mammals?
A
- Differences in feeding behaviour
- Solitary predators (felids) deliver powerful canine killing bites, and have strong canine bite region
- Social (pack) hunters (canids and hyaenids) deliver shallow bites, and display a weaker canine bite
17
Q
How could you reconstruct a paleo-ecosystem?
A
- Body mass - prey size relationship
- Morphology and bite patterns
- Tooth wear patterns (microwear and breakage)
18
Q
What is cryptic speciation?
A
- Genetics revealing divergence from a long time prior, making two separate species
- Seen in clouded leopards
19
Q
How do jaw muscles differ in herbivores and carnivores?
A
- Carnivores have well-developed temporalis muscle for seizing and holding prey
- Herbivores have a large masseter muscle for grinding
20
Q
What are the adaptations seen in sanguinivorous bats?
A
- Modified rostrum with large incisors and canines
- Small cheek teeth
- Tongue with grooves at border (work like straws)
- Stomach is long and tubular, highly distendible
- Small intestine is thin
- Kidneys modified to quickly process water
21
Q
What are the two compounds in the venom of vampire bats?
A
- DSPA and Draculin
22
Q
What organs in the nose of bats are sensitive to infrared radiation?
A
- Pit organs
23
Q
What are callosities?
A
- Whale lice and barnacles that grow on some species
24
Q
What are the two main groups of herbivores?
A
- Broswers and grazers; Gnawers
- Browsers: Feed primarily on stems, twigs, buds, and leaves
- Grazers: Feed primarily on grasses and forbs
- Gnawers (rodents and lagomorphs)
25
# Define the following terms:
- Graminivore
- Gumivore
- Folivore
- Frugivore
- Granivore
- Nectarivore
- Graminivore = grasses
- Gumivore = exudates of trees (saps, resins, gums)
- Folivore = leaves
- Frugivore = fruit
- Granivore = seeds
- Nectarivore = nectar
26
How do upper incisors differ in ruminant vs. non-ruminant herbivores?
- Ruminant herbivores have lost their upper incisors and their lower incisors bite against a callous pad on the upper gum
27
What is the reproductive period of male African elephants called?
- Musth
28
What can be a source of mortality in older elephants?
- Molar wear - inefficient food processing
29
What are the four compartments of ruminant's stomach? What function do they serve?
- Rumen (largest chamber where food is moistened, kneaded, and mixed with microorganisms)
- Reticulum (area where "cud" is formed and can be regurgitated, allowing animal to re-chew material)
- Omasum (further kneading occurs)
- Abomasum (fourth and final chamber, true stomach, digestive enzymes are secreted and escaping microorganisms are killed)
30
Difference between foregut and hindgut fermentation?
- Foregut fermentation is more efficient because microorganisms digestion starts sooner and foregut can digest some of the microorganisms
- Hindgut fermenters do not digest microorganisms
- Hindgut fermenters are efficient if food is high in protein and if forage is dominated by indigestible material
31
Difference between cercopithecine and colobine monkeys?
- Cercopithecine = have cheek pouches
- Colobines = lack cheek pouches, have sacculated stomachs (evolved for leaf diet), large salivary glands, most folivores
32
What is the metabolic rate so low in sloths?
- In arboreal folivores, muscle mass makes up only small proportion of body which therefore has larger proportion of tissue with low metabolic rate
- Leaves have low caloric density. Since maximal daily bulk that can be processed is limited, energy available from leaves is low - constraint on growth
- Number of toxic substances, including alkaloids, terpenes, and phenols, are present in leaves. Low BMR in leaf-eating mammals may reduce the absorption of these substances (limit may be on how fast liver can detoxify compounds)
33
Which bone is the "false thumb" in giant pandas and red pandas?
- Radial sesamoid (carpal bone)
34
What is mycophagy?
- Fungus eating species
35
What are the constraints on bears consuming wild fruits for fall energy?
- Intake rate
- Physiological capacity of GI tract
- Metabolic efficiency of gain in body mass
- Foraging efficiencies constrain growth rates
36
Marginal value theorem predicts that individuals will stay longer in what situations?
- Profitable patch
- As distance between patches increases
- When environment as a whole is less profitable
37
What are the two different types of caches?
- Scatter hoarding = Different locations, need spatial memory
- Larder hoarding = Bring back to one spot only
38
What are infrasound and ultrasound?
- Infrasound = < 20 Hz
| - Ultrasound = > 20,000 Hz
39
What are some of the documented, short-term responses of cetaceans to human-produced sound?
- Longer dive times
- Shorter surface intervals
- Evasive movements away from source of sound
- Attempts to shield young
- Increase in swimming speed
- Changes in song note durations
- Leave area
40
What organ in sperm whales may act to modify buoyancy or as a lens to focus outgoing sound waves?
What structure in the forehead of all whales serves as acoustic lens for echolocation sound production?
How do cetaceans generate clicks?
- Spermaceti organ
- Cetacean melon
- Via structure just below blowhole called "monkey's lips" that smack together
41
What can bats detect through echolocation?
- Distance and speed (return frequency)
- Size (subtended angle)
- Time delay and amplitude give azimuth (location)
- Inference patterns with inner ear surface gives elevation
42
Difference between constant frequency signals and frequency modulation signals?
- Constant frequency signals = Constant frequency have significant time duration; good for detecting presence, and through Doppler shift, whether prey is approaching or departing
- Frequency modulation signals = Short duration, but sweep broad frequency range; ideally suited to determine size, shape, surface qualities, range of target (shifts in frequency to get needed information)
43
Difference between ethmoturbinates and maxilloturbinates?
- Ethmoturbinates = Olfaction
| - Maxilloturbinates = Respiration (heat and water conservation)
44
What is mosaic evolution?
- Pattern wherein the different compounds of an existing structure evolved at different rates
45
What two glands play a major role in controlling the endocrine system?
- Hypothalamus
- Pituitary gland
- Hypothalamus controls pituitary, and pituitary controls release of hormones
46
What are endocrine glands?
- Specialized groups of cells that produce chemical substances called hormones that act as messengers to cells throughout body (main components = pituitary, pancreas, ovaries, testes, thyroid, adrenals)
47
Follicle stimulating hormone (FSH)
- Produced by anterior pituitary
- Stimulates ovarian follicles and estrogen secretion in females
- Stimulates spermatogenesis in males and testosterone secretion
48
LH
- Produced by anterior pituitary
| - Stimulates corpus luteum development and production of progesterone in females
49
Estrogen
- Any of the C18 steroir hormones that generate estrus in females
- Produced by developing follicles (stimulated by FSH)
50
Progesterone
- Steroid hormone produced in follicle and corpus luteum
| - Promotes growth of uterine lining (allows egg implantation)
51
Oxytocin
- Produced in anterior pituitary
- Causes rhythmical contractions of uterus during parturition
- Enhances milk "letdown"
52
Prolactin
- Produced in anterior pituitary
- Reproduction and water balance
- Promotes corpus luteum in ovaries
- Promotes milk production
53
Testosterone
- Steroid hormone secreted by testes
| - Responsible for development and maintenance of sexual characteristics and sperm production
54
What is cytochrome P450?
- Enzymes
- Body's mechanism to dispose of potentially harmful substances by making them more water-soluble
- Vital to formation of cholesterol and steroids
- Abundant in liver
55
What is the function of the thyroid gland?
- Regulates metabolic activities by hormone thyroxin (thyroid gland is regulated by anterior pituitary)
- Regulates cellular respiration
- Cold adapted individuals have higher thyroid output than those not exposed to cold
56
What are the five types of WBCs?
1. Neutrophils (consume foreign particles, primarily bacteria and fungi)
2. Lymphocytes (produce antibodies - IgA (mucosal), IgD (lymphocyte cell membrane), IgE (only in mammals - allergies and parasites), IgG (most abundant in serum), and IgM (first AB present in infants)
3. Monocytes (convert to macrophages and consume bacteria and viruses)
4. Eosinophils (destroy and consume antigen-antibody complexes)
5. Basophils (congregate at tissues with inflammation or infection and release histamines)
57
What are the four lines of defense in mammals?
1. Skin and lining of digestive system, respiratory system (mechanical)
2. Inflammatory reaction (swelling, WBCs accumulate)
3. Proteins activated at wound sites
4. Immune reactions (immunoglobulins, ABs)
58
Describe the immune reaction
- Body recognizes bacteria/virus
- Lymphocytes make ABs that seek out and form complexes with antigens
- Complexes are engulfed and destroyed by other WBCs
59
Three types of biological rhythms
- Ultradian ( < 24 hrs.)
- Circadian ( = 24 hours)
- Circannual ( = 1 year)
60
Three aspects of rhythm
- Period (length of time to complete one cycle)
- Phase (particular point of cycle)
- Amplitude (difference in value between peak and trough of a cycle)
61
Three possible hypotheses for lion's mane
1. Protect neck in fights with other males
2. Signal of male condition
3. Dark manes indicate maturity, increased testosterone, and nutrition
62
What are some ways that animals can avoid cold or resist cold?
- Avoid cold through body size, appendages, colouration, modification of microclimate, food hoarding, decreased activity, decreased mass, dormancy
- Resist cold by increases thermogenic activity through BMR, NST, and shivering
63
What is the total amount of heat lost from an animal equivalent to?
What is the approximate measure of metabolic rate?
- The amount of heat conducted from animal's core to outside of its body
- Slope of 0.75 indicates metabolic rate scales body mass to 3/4 power
64
What is allometric growth?
- Differential growth of body parts resulting in a change in shape/proportion with increase in size
65
What is conduction? What is it dependent on?
- Energy transfer through molecular collision
- Must have contact between media involved in heat transfer
- Dependent on: SA of exposure, efficiency of heat transfer through conducting media, temperature difference between two medias
66
What is convection? What is it influenced by?
- Energy transfer via moving air or water
- Both total area exposed to moving fluid and temperature difference between two media are important to determining total heat loss
- Heat transfer rate influenced by thickness of boundary layer enveloping object, which is influenced by: Size and shape of object, surface roughness, wind speed
67
What is the boundary layer?
- Layer of non-moving air that directly surrounds an organism
68
What is radiation? What two properties determine radiated energy?
- Propagation of energy through space
- Properties that determine radiated energy: Temperature (independent of ambient temperature) and characteristic efficiency of radiant energy transfer (termed emissivity)
- In homeotherms, heat loss by radiation remains relatively constant over the years since body temperature does not vary
69
What is latent heat of exchange?
- Heat energy either tied up or liberated with phase changes of water
70
What are three ways that mammals can maintain a constant metabolic rate (and therefore a constant temperature)?
- Decrease thermal conductivity (k in equation)
- Decrease surface area exposed (A)
- Increase thickness of insulating layer (d)
71
What is white adipose tissue?
- Major fatty tissue of mammals that functions as insulation, mechanical support, buoyancy, streamlining, and as an energy reserve
72
What are some ways that animals keep warm?
- Insulation (white adipose tissue)
- Decrease body temperature (e.g., nightly torpor in bats)
- Modify microclimate (build nest, go underground)
- Build communal nests with other mammals
- Increase metabolic rate to balance heat loss
73
What is the point called when mammals will increase their metabolic rate to balance heat loss?
- Lower critical temperature (LCT)
74
What happens below the LCT in mammals?
- Physiological thermoregulation takes over
- Increased ability for "non-shivering" heat production seen in acclimatization to cold in small mammals (increase in brown fat near vital organs)
- Brown fat has higher mitochondria and therefore higher rate of oxygen consumption and heat produced, compared to white fat
75
How does brown fat work?
- Nerve signal from hypothalamus in brain to adrenal medulla signals secretion of noradrenaline in bloodstream
- NA stimulates rapid heat production in mitochondria-rich brown fat tissue, concentrated in intrascapular region close to vital organs
- Highly vascular to transfer heat to blood and body
76
What is the last resort in mammals to stay warm?
- Shivering thermogenesis
| - Energetically costly
77
What is Dehnel's phenomena?
- Small mammals can undergo a general decline in body mass during winter
- Decreases energetic needs over winter
78
What are some adaptations of camels to cope with desert ecosystems?
- Vary body temperature as a device for saving water (drop body temperature at night to avoid losing water to the environment)
- Can tolerate water loss up to 30% of their body mass, likely due to fact that they can maintain blood plasma volumes near normal levels during dehydration
- Can concentrate urine and absorb water from fecal material
- Can rehydrate quickly, taking in high amounts of water in only a few minutes
- Kidneys can process sodium chloride solution (can drink salt water more concentrated than ocean)
- Thick fur stops its skin from absorbing heat
- Also has sweat glands to cool skin
- Also use behavioural techniques to cool themselves, lying on ground that has been cooled by radiation in the morning and lying side-by-side to prevent solar radiation from permeating body of each mammal
79
How are appendages adapted in mammals to withstand cold?
- Countercurrent system of blood flow
- When air temperature is low enough, superficial veins in extremities constrict, increasing flow resistance, shunting more blood through deeper veins lying closer to arteries
- Warm arterial blood gives up its heat to cold blood returning from extremities
- Short-circuited flow of heat - arterial blood is pre-cooled, venous blood is pre-warmed
80
Why do animals hibernate?
- Save energy
| - Avoid predation risk when food is scarce
81
What features do desert-dwelling rodents display that favour body water conservation?
- Efficient kidneys
- Low fecal water content
- Comparatively low evaporative water loss
- Do not drink free water and depend on pre-formed water in their diet and water from oxidation of food (kangaroo rats)
82
What sources of food are ideal in high and low humidity environments?
- Low humidity - oxidation of carbs produces net metabolic gain, lipids result in net loss of water, proteins produce severe loss of water
- High humidity - carbs produce net water gain, lipids produce large water gain, proteins produce large water loss
83
What are two different cooling systems in mammals?
- Sweating (evaporative cooling) - only effective is water is abundant (loss of water through apocrine and eccrine sweat glands)
- Panting (canids have few sweat glands to rapid, shallow breathing increases evaporative heat loss from upper respiratory tract)
84
What is respiratory heat exchange?
- Acts as water conservation measure where moisture in expired air condenses in nasal passages which have a large surface area in desert species
85
How can insulation be useful in hot weather?
- Fur can be used to retard heat movement from the environment to the body (hair heated by sun radiates heat and loses heat by convection)
86
What is a thermal window?
- Bare or sparsely furred areas of certain mammals that function as sites through which heat can be lost
87
What is estivation?
- Period of dormancy in reaction to dry/hot conditions
88
What form do monotreme sperm have?
- Filiform
89
What feature do monotremes and marsupials lack, that eutherians have?
- Corpus callosum
90
What kind of placenta do marsupials have?
- Choriovitilline placenta
- Membrane is less developed
- Maternal-offspring transfer is less efficient
91
What type of sperm do marsupials have?
- Paired sperm
92
What does dioecious mean?
- Male and female reproductive organs occur in different organisms (all mammals)
93
What type of penis do cetaceans have?
- Fibroelastic penis (always semi-rigid)
| - Internal genitalia
94
What are the four eutherian reproductive tract types?
- Duplex = 2 uteri, each with cervix, most primitive condition
- Bipartite = Fusion of distal ends of uteri (most carnivores and whales)
- Bicornuate = Greater fusion of distal ends of uteri opening; horns of uterus separate but enter vagina by single cervix (most common)
- Simplex = Separation between uterine horns lacking, single uterus opens into vagina through one cervix
95
Estrous cycle
- Time period from one period of estrous to the next
96
Monestrous
- Species with only one estrous cycle per year
97
Polyestrous
- Species with multiple cycles per year
98
Anestrous
- Non-breeding, quiescent condition of reproductive cycle
99
Proestrous
- Beginning stage of estrous cycle
100
Estrous
- Period when female will permit copulation
101
What happens to estrogen during estrous cycle?
- Gradually increases
- Prompts build-up of uterine walls
- Stimulate pituitary to produce FSH for follicular development
102
What happens to progesterone during estrous cycle?
- Gradually increases
- Prepares uterus
- Uterine walls continue to build up due to progesterone
103
Ovarian activity during estrous?
- Old follicle becomes corpus luteum, secretes LH, keeps progesterone levels up
104
What happens to hormone levels if there is no pregnancy?
- Progesterone decreases
| - LH decreases as old corpus luteum loses secretory function
105
Difference between spontaneous and induced ovulation?
- Spontaneous = Without copulation
| - Induced = Egg is shed within a few hours following copulation
106
Difference between delayed fertilization/ovulation, delayed development, and delayed implantation?
- Delayed fertilization/ovulation = copulate in autumn, before hibernating, ovulation is delayed, implantation of blastocyst occurs after fertilization
- Delayed development = Blastocyst implants after fertilization, development is slowed down
- Delayed implantation = Ovulation, fertilization, and zygote development to blastocyst occur normally; blastocyst ceased development, suspended in reproductive tract; when environmental conditions are favourable, blastocyst will implant
107
What does didelphous refer to?
- Marsupials reproductive tract (uteri, oviduct, and vagina canals are paired)
108
Describe the choriovitelline placenta
- Yolk sac enlarged
- Blastocyst does not sink deeply into endometrium - shallow depression
- Limited amount of nutrition from uterine lining
- Short gestation
- Most marsupials
109
Describe chorioallantoic placenta
- Blastocyst sinks deep into endometrium
- Strong adhesion
- Increase SA for efficient exchange of substances
- Bandicoots
110
Describe the non-deciduous placenta
- Placenta with least intimacy between maternal and fetal membrane
- Minimal attachment of villi in uterine wall
- Less bleeding when shed
- Placenta is shed
- Pigs, lemurs, horses, whales
111
Describe the deciduous placenta
- Close attachment, extensive erosion of uterine wall
| - Bleeding
112
What are the different types of placental scars?
- Nulliparous = Female that has never given birth
- Parous = Female that is pregnant/shows signs of previous pregnancy
- Multiparous = Female that has had several litters/young, have placental scars of different ages
113
Function of trophoblast?
- Prevent immunorejection between maternal and fetal tissues
- Marsupials = Developing embryo protected by shell membrane, later in development shell membrane disappears, short gestation to prevent rejection
- Eutherians = Lack shell membrane, early development zygote is protected by zona pellucida, later by trophoblast, longer gestation
114
What is embryonic diapause?
- Opportunistic reproduction
| - E.g., red kangaroos - have three young at the same time
115
What is the composition of mammalian milk?
- Colostrum = protein-rich fluid containing antibodies
- Lysozyme = Kills bacteria and fungi
- Mammals in north have high fat and high protein milk
- Milk in early and late lactation have high protein, low sugar
116
Difference between discrete and graded communication signals?
- Discrete are all or none (only convey one message; binary)
| - Graded are more variable signals, communicate motivation by intensity (analog, varying continuously, more complex)
117
What is the sound window?
- Use of frequencies for communication that are transmitted through environment with little loss of strength (attenuation)
118
What are the functions of communication?
- Ultimately, to increase fitness
| - Group spacing and contact (increase/decrease/maintain distance between group members)
119
What is phenotypic matching? How might it work? What are the benefits?
- Mechanism by which kin may recognize one another
- May involve MHC (recognize self from non-self), may result in urinary odour cues that can be used to identify genetic similarities
- May lead to more heterozygous offspring with greater disease resistance
120
What are some other, more general functions of communication?
- Social status and aggression
- Alarm calls to alert members to danger
- Semantic (of or relating to meaning of signals specially applied to denote the use of different alarm signals to warn about different predators)
- Hunting for food
- Giving/soliciting care
- Soliciting play
121
What is agonistic behaviour?
- Behaviour patterns used during conflict with conspecific, including overt aggression, threats, and retreats/escapes
122
What are different forms of agonistic behaviour?
- Territorial (exclude other from some physical space)
- Dominance (control over conspecifics as a result of previous encounter)
- Sexual (use of threats and physical punishment, usually by males, to obtain and retain mates)
- Parental (attacks on intruders when young are present)
- Parental-offspring (disciplinary actions by parent against offspring, often associated with weaning)
123
What are the two forms of competition for resources?
- Exploitation (use resources and deprive others of them without interacting)
- Interference (organisms interact so as to decrease another's access to/use of resources)
124
What are the four natural orders of selection?
- 1st order of selection = Selection of physical/geographic range of species
- 2nd order of selection = Determines home range of individual/social group
- 3rd order of selection = Usage of various habitat components within home range
- 4th order of selection = Actual procurement of food items from site
125
What is economic defendability?
- State in which the defence of a resource yields benefits that outweigh the costs of defending it
- Distribution of limited resources (temporal and spatial distribution)
- Two key factors to territories = limited resources and defendability
126
What is a lek?
- Area used, usually consistently, for courtship displays
127
What are the reasons for infanticide?
- Mating opportunities
- Decrease intraspecific competition
- Nutrition gain
- Maternal infanticide (parental manipulation of progeny)
- Social pathology
128
What is anisogamy?
- Differences in gamete size and cost causes different reproductive behaviour patterns in males and females
- Male success linked to how many females he can inseminate; female success linked to how many eggs and young she can produce
129
What is Bateman's principle/gradient?
- Large variation in reproductive success of males compared to females in relation to number of mates they obtain
- Males that copulate the most sire the most offspring; females only need to mate once to produce max number of offspring
130
What are the three variables in Bateman's principle?
- Variance in mating success
- Variance in offspring number
- Relationship between offspring number and mating success
131
What is sexual selection?
- Process that produces anatomical and behavioural traits which affect individual's ability to acquire mates
132
Difference between intersexual and intrasexual selection?
- Intersexual selection = Traits/behaviours influencing mate choice (females choosing males) (males advertise that they are "fit")
- Intrasexual selection = Traits/behaviours to best compete for access to mates of opposite sex (generally male to male)
133
What is the operational sex ratio?
-Ratio of males to females that are ready to mate in a population at any one time
134
What is the Bruce effect?
- Early in pregnancy, females would abort fetus and become receptive when strange male joins group
135
When do facultative and obligate monogamy occur?
- Facultative = densities are low; male home range overlaps with female
- Obligate = Male parental investment is required for offspring survival
136
Different types of polygyny
- Resource defence polygyny = Males defend areas with critical feeding and nesting sites for reproduction
- Female defence polygyny = Females are gregarious (unrelated to reproduction); males monopolize harem
- Male defence polygyny = Males not involve in parental care and have little opportunity to control resources/mates (leks)
137
When would polyandry occur?
- Food availability is variable or when breeding success is low due to high predation on young
138
What is the concept of dispersal? What are the two types?
- Directional movement to a new area
- Natal dispersal (from site of birth to new breeding area by juveniles when they reach sexual maturity)
- Breeding dispersal (from one breeding site to another)
139
What is the purpose of dispersal?
- Maximize breeding fitness
- Two opposing evolutionary forces: Inbreeding depression (decreased fitness as result of inbreeding) and outbreeding depression (decreased fitness due to mating between two distinct, distantly related individuals)
- Minimize competition between conspecifics (females stay home (philopatric) to defend and obtain resources; males range farther to increase encounters with females)
- Avoids competition between closely related individuals as a way to increase inclusive fitness
140
Difference between shifter disperser, philopatric disperser, and one-way disperser
- Shift = Leaves natal area in step-wise pattern
- Philopatric = Doesn't disperse
- One-way = Leaves natal range
141
What are ranging and station-keeping?
- Ranging = Exploratory movements associated with suitable habitat for home range
- Station-keeping = Movements keeping animal within its home range
142
Six conditions of migration
1. Persistent movement of longer duration than occurs during ranging/station keeping
2. Straightened-out movement relative to turning frequency of station-keeping/ranging
3. Initial suppression/inhibition of responses to stimuli that arrest other movement but with subsequent enhancement of these responses
4. Activity patterns particular to departure and arrival
5. Use of surrogate cues like photoperiod or population density to abandon habitats before they deteriorate
6. Specific patterns of energy and internal resource allocation to support movement
143
Different methods of homing
- Path integration = Internal, continuous updating of position relative to starting condition
- Piloting (landmarks) = Use external cues for georeferencing locally
- Sun compass = Orient via position of sun
- Magnetic compass = Orient via geomagnetic lines of Earth
144
What factors play into habitat selection?
- Abiotic factors
- Biotic factors
- Genetic factors
145
What is ideal free distribution and the three assumptions behind it?
- Individuals will sort themselves into habitats of varying quality so that fitness is homogeneous across the population
- Three assumptions: All individuals within a population have perfect knowledge of habitat quality, are free to search out habitat with no cost, and are equal competitors
146
What is the "habitat-matching" prediction for IFD?
- Population distribution correlates positively with habitat quality
- As competitor density increases in best habitat, colonization of poorer quality habitats becomes favourable, but only at reduced densities
147
What are some ways to sample parasites?
- Trap hosts, trap parasites, necropsies, scat, remote cameras, blood sample
148
Why study parasites?
- Prevalence
- Intensity
- Transmission (localized or spreading?)
149
What are platyhelminths?
- Cestodes (tape worms), trematodes (blood flukes)
| - Most with indirect life cycles
150
What are nematodes?
- Microscopic
- Unsegmented worms
- Usually direct life cycle
151
Arthropods
- Ectoparasites
- E.g., Sacroptic mange
- Lead to indirect mortality
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What is a zoonosis?
- Disease transmitted from animals to humans
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What is a vector?
- Organism, often invertebrate arthropod, that transmits pathogen from reservoir to host
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What factors can shape a parasite's specificity to their host?
- Host's ecology
- Ancestor's ecology
- Adaptations to exploit host
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What are some conditions for direct mortality?
- When death of host facilitates transmission (e.g. rabies virus)
- Generalist pathogen with many hosts
- Wide-ranging parasite in time and space (yellow fever in howler monkeys - can persist by moving across large areas for long periods)
- Accidental hosts (rinderpest virus)
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What is the difference between an enzootic phase and an epizootic outbreak?
- Enzootic phase = parasite at constant low levels
| - Epizootic outbreak = Transmission increases; number of infected individuals grows
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How can good nutrition influence disease?
- Increases resilience
- Increases resistance
- Increases immune function
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What types of interactions can affect parasites?
- Sociality (grooming, limited exposure to unrelated individuals, territoriality, contact rates)
- Sexual selection (immunocompetence handicap principle - strongest males can afford to have parasites)
- Competition (apparent competition)
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What is Gloger's rule?
- Races in warm and humid areas are more heavily pigmented than those in cool and dry areas
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What is heimal threshold?
- Presence of a sufficient depth of snow (insulates subterranean environment against widely fluctuating environmental temperatures)
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What is osmoregulation?
- Maintenance of proper internal salt and water concentrations
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Semelparity vs. iteroparity
- Semelparity = bear young all one once
- Iteroparity = Larger body size, develop more slowly, longer life span, bear young at repeated intervals (K-selected, typically)
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Allee effect
- Minimum group size below which populations decline
