Chapter 8 Flashcards
1
Q
What is a mating system?
A
the way animals associate for purposes for reproduction
2
Q
What is monogamy?
A
male and female that stay together per reproductive bout/ season
3
Q
What is polygyny and polyandry?
A
- polygyny- one male, multiple females
- polyandry- one female, multiple males
4
Q
Why might some species exhibit more than one mating pattern?
A
depends on sex or other circumstances
5
Q
What mating patterns do honeybees exhibit?
A
- female honey bees are polyandrous
- males are monogmous and mate once
6
Q
How do bowerbirds exhibit mating patterns?
A
- males are polygynous
- females are monogomous
7
Q
Green catbirds mating patterns
A
both are monogomous
8
Q
What are some darwinian puzzles for mating patterns (3)
A
- why are males ever voluntarily monogamous?
- why do females of some species practice polyandry?
- why do males of different species differ in the tactics they use to achieve polygyny?
9
Q
What should we expect male mating patterns to be?
A
males usually compete for mates, and if successful are polygynists, and should have higher fitness than monogamous rivals
10
Q
Why is male house wrens being polygynists advantageous?
A
male house wrens that get two females father more than monogamous males
11
Q
Why might sexual suicide occur?
A
those that commit sexual suicide may increase fertilization success
12
Q
net gain from posthumous guarding may exceed costs if… (2)
A
- mate has the potential to remain receptive after one mating
- males probability of finding a second female is very low
13
Q
How do harlequin shrimop exhibit mate guarding
A
- males spend at least weeks with one female
- ratio of searching males to receptive females are highly male biased
- females are more dispersed and rarely mate
14
Q
What is mate assistance hypothesis?
A
males may remain with a single female to help her (paternal care or protection of offspring)
15
Q
How do crickets exhibit mate assistance hypothesis?
A
- guarded females had lower predation risk
- males allowed mates to escape first
16
Q
Why might self-sacrificing be beneficial?
A
in sacrificial males, offsprings that survive compensate for the lost chances of further reproduction
17
Q
How are seahorse pairs syncrhonized? (2)
A
- female provides a batch of eggs right after the previous ones hatch
- if male loses his mate, he may lose out on time finding a new mate
18
Q
What is female-enforced monogamy? (2)
A
- males may benefit from being polygynous, but females blocks attempts so she can monopolize parental assistance
- similar to mate guarding, except that its the female that is guarding
19
Q
How do burying beetles exhibit female-enforced monogamy?
A
- females with a male partner are aggressive to other females
- pairs work together to bury carcass to feed offspring
- female lays eggs in carcass
- after female lays eggs, males releases a sex pheromone for other females on a perch
- if another females were to lay eggs on the same carcass, offspring would compete for food
- female pair may knock male off a perch to prevent this
19
Q
How do emeral coral goby exhibit feamle-enforced monogamy?
A
- dominant females may force partner to be monogamous by being hostile to females
- subordinate females must accept this, as leaving imay mean death
- if subordinate females live long enough, the may assume the dominant status
20
Q
Why is monogamy rare in mammals? (2)
A
- monogamy is rare in mammals, as there is a huge investment in females for parental care
- sexual selection favors male mammals who cannot be pregnant or offer milk should try to be polygynous
21
Q
What should we predict in mammals if male assistance hypothesis is correct?
A
if MAH applies to mammals, males that are paternal should be monogamous
22
Q
How do djungarian hamsters exhibit MAH?
A
male delivers pups and can enhance offspring survival
23
Q
How do california mouse exhibit MAH?
A
- pairs can raise a litter of pups in labs
- single females did more poorly
24
What might infanticide favor?
- Parental males in some mammals defends offspring from infanticidal males
- infanticide may favor monogamy
25
What pattern is seen in male monogamy?
- males tend to live in long term pairs when females are dispersed
- this favors male mate guarding
26
How do rock-haunting opossums exhibit mate guarding?
males are dispersed,, and males moving must face territorial males
27
How is MAH seen in junco birds?
males takes care of first brood with female incubates second clutch
28
How is MAH seen in starling birds?
those with biparental care stayed warmer, developed more quickly, and had a higher chance of hatching
29
What can testosterone do in male parents
testosterone is seen to make worse male parents
30
given that fitness gained by these males increase only if they exclusively care for their own genetic offspring…
monogomous males should sire all the offspring of their mates
31
Why dont monogomous males always sire all offsprings in birds (3)
- in most birds, social monogamy is not sexual monogamy
- in most bird species, some females engage in extra pair copulations
- monogamous males are always at risk of cuckoldry
32
Why do males attach himself to a single female, only to have her use another male sperm to fertilize some or all her eggs? (2)
- males themselves may take advantage of extra pair copulation
- those with gaudy ornaments/displays may avoid costs of monogamy
33
why do such males fail to engage in extra pair copulation? (3)
- role that female choice has in who gets to mate
- males wit poor parental care are likely to drop out of reproductive competition completely
- only real option left
34
What might favor polyandry?
constraints imposed by choosy females and competitors
35
How do galapagos hawks exhibit mating systems?
- males can be monogamous or polyandrous
- polyandrous males may be when suitable territories lack
- leads to male biased sex ratio, where males compete for limited number of territorial females
- up to 8 males form a long term bond with a single female, and participate in parental care
- each male has an equal chance of fertilization
36
Wattled Jacana and Red Pharalope matign system
- males mate with territory owner polyandrous females
- each gets a clutch of eggs to care for
- monogous males are likely yo care for offspring that aren’t theirs
- males must put up with this, or lose chance of reproducing at all
37
sandpipers mating system
- female spotted sandpipers are larger, and fight others for mates and territories
- first males to mate gets own clutch, subsequent males may have mixed eggs
38
Cricts female costs of polyandry (3)
- time and energy finding males
- increased predation
- increased chance of STD
39
What should we expect if STD is high for polyandrous females?
they should have stronger immune systems than monogamous species
- WBC in females were higher in polyandrous
40
What is fertility insurance hypothesis?
mating with several males reduce risk that some of the females ova will remain unfertilized because some partners are infertile
41
What is the good genes hypothesis for polyandry?
a female mates with more than one male because her social partner is of lower genetic quality than her extra pair partner whose genese will imrpvoe offspring viability
42
What is genetic compatibility hypothesis?
mating with several males icnreases genetic variety of available sperm to the female, which boosts chance that females will receive some sperms whose DNA is compatible
43
What is more resources hypothesis?
more mates means more resources received from the sexual partners of a female
44
What is the more care hypothesis?
more mates means more caregiver to rear female offspring
45
What is better protection hypothesis?
more mates means more protectors to keep other males from sexually harassing
46
What is infactnticide reduction hypothessi
more mates means greater uncertainty about paternity over infant when it is born and the fewer males with no stake in the welfare of the offspring
47
How do redwing blackbirds exhibit fertility insurance hypothesis?
eggs of polyandrous females were more likely to hatch than monogamous females
48
How do african tree frogs exhibit good genes hypothesis?
clutches fertilized by more males were likely to survive than monogamous clutches
49
How do yellow-toothed cavies exhibit good genes hypothesis?
payoff for polyandry is lower still birth and higher survival
50
How do dark eyed- Juncos support polyandry and good genes?
offspring of females and their extra-pair mates were more likely to survive than offsprings of females and their social mates
sons of EPC tend to engage in EPC
51
How does polyandry provide fitness in Juncos?
females contribute more to her offspring of EPC
more nutrients means more fit offspring
52
How do fairy wren support polyandry and good genes hypothesis?
socially bonded pairs lives in territories with mate and young male helpers
breeding females sneak compilation with distant males
social males lose out unless they also have EPC
53
How do crickets support polyandry and good genes?
male attractiness is hereditary
sons of sexually successful field crickets were more appealing to females than sons of males with no success
54
How does polyandry support genetic compatibility? (3)
increase chance of obtaining genetically complementary sperm for fertilization
particularly compatible genotypes may result in highly viable progeny
high levels of heterozygosity may be advantegeous
55
we can predict that females will have more EPC with males that are... (2)
genetically dissimilar
highly heterozygous
56
How do pseudoscorpions support polyandry and genetic compatibility?
polyandrous vs experimental monogamous females
- no male had higher reproductive success with either females
- match between two gametic genomes caused higher reproductive success
- male quality wasn’t particularly helpful, but the genotype (compatibility) it provided was
female chance of compatible sperm increased with partners
- females should prefer to mate with new males
- supported in experiment
57
What is the Coolidge effect?
mating with the same individuals doesn’t provide added reproductive success
58
How does the superb starling support polyandry and genetic compatibility?
- females chose partners outside of social groups, because social mates were less heterozygous
- offsprings of EPC were more heterozygous
59
How did female bluethroats seek out mate?
EPC were more heterozygous and had stronger immune systems
60
How did mandrils seek out mate? (2)
- dominant males father more offsprings
- females tend to reproduce with genetically compatible males
61
why would some Apis species replace monogamy with extreme polyandry?
- Single vs multiple insemination queens
- none single father hives survived winters
- disease resistance in polyandrous colonies
- stems from higher diversity of workers
62
How do blackbirds benefit from polyandry and material benefit?
females may forage in territories of EPC
63
How do bees benefit from polyandry and material benefit?
females may copulate with territory males every time they enter a territory for pollen and nectar
64
What are two examples of material benefits, especially in insects?
- some insects can obtain water via ejaculate when dehydrated
- nuptial gifts
65
How do butterflies benefit from material benefit and polyandry?
- polyandrous males can bribe by giving spermatophore
- greater reproductive outputs for more polyandrous females
66
How do European dunnocks benefit from polyandry and material benefit?
- females living in territory of an alpha male may encourage subordinate male to stay by copulating with him
- females copulate multiple times before laying eggs
- both males help in parental care
- females will spend more time copulating with males who are less often around to reach her parental threshold
67
evidence that direct/indirect benefits of polyandry aren’t high in birds
- indirect benefits were close to zero, and negative direct benefits
- female birds may not gain from polyandry
- males gains from polygyny
68
What is convenience polyandry?
females don’t gain benefits from extra male copulations, but costs less to copulate than fight off sexual harassers
69
How do males often acquire mates?
defending territories
70
What is female defense polygyny?
males go to where females are and fight with other males there to monopolize them
71
How do sheeps exhibit female defense polygyny?
females form groups against predators and attract males
72
How do lions exhibit female defense polygyny?
fights over prides of females (females form groups for hunting territory and protection against infanticide)
73
How do orpendula birds exhibit female defense polygyny?
- males try to control clusters of nesting females
- dominant males can secure up to 80% of matings by driving away subordinates
- as colony size increases, copulations go down as male struggle to keep up
74
How do ants exhibit female defense polygyny?
- some species have large numbers of female queens
- males of colonies fight to access them
75
How doamphipods exhibit female defense polygyny?
males glue females to pebbles to house up to three females
76
What causes female defense polygyny? (2)
based on idea that female distribution patterns are the cause
when females occurs in clusters, males will compete for access to clusters
77
What is resource defense polygyny?
waits for females to come to them, defending territories that have good vegetation and for egg habitat or food
78
How do antlered flies exhibit resource defense polygyny?
defends rot spots on logs that females use to lay eggs
79
How do African cichlid fish exhibit resource defense polygyny?
- females deposit eggs in empty snail shells and stay inside until hatchlings can leave nest
- males defend nest sites and collect/ steal shells
80
How do Dunnocks exhibit resource defense polygyny?
- when provided food for limited locations, female home ranges contracted
- shifted from polyandry to polygynyW
81
What is lek polygyny? (2)
defend territories with only a display, but no real resources
males fight to control an area for a display dispersed over a lek (traditional display ground)
82
Why form leks? (2)
- leks evolved when other reproductive tactics don’t pay off for females
- female resources are not clustered
83
when there are no clustering of females or resources, why lek instead of searching?
cost decrease for group lekkers
84
What is a hotspot?
males cluster in places that receptive females travel through
85
What is a hotshot?
subordinate males cluster around attractive males in order to interact with females drawn to the hotshot
86
What is female preference?
males cluster because females like sites with large groups of males- allows them a way to quickly compare quality of mates
87
What happens when creating artificial leks and decoys?
- females decoys failed to draw in males
- rejects hotspot
- male decoys attracted females and males
- supports hotshot
- more females per decoy were attracted to multiple male decoys
- supports female preference
88
What happens when successful males are removed?
- males should move into hotspot areas if hotspot was correct
- if hotshot was correct, males should cluster to other popular males
89
What happens when successful male snipes are removed?
- removal of dominant males led to subordinate males to leave territories
- removal of subordinates were quickly replaced
- supports hotshot
90
What is scramble competition polygyny?
males skip combative territoriality, just try to outrace rival males to receptive females
91
When does scramble competition polygyny occur? (2)
- in situations were resources or females are widely dispersed
- depends upon being vigilant, perceptive, and persistent, not aggressive
92
How do ground squirrels support scramble competition polygyny?
- females are dispersed and only receptive sexually shortly
- first male to find female has a high fertilization rate
- success depends on memory of location of females
93
What is explosive breeding assemblage? (3)
- extreme CP with a compressed breeding seasons
- males are under pressure to be at the right place and time
- males can give up territoriality to encounter receptive females as much as possible
94
What should a female do when selection of an already mated males means sharing resources under his control with other females? (2)
- there should be a point at which a female can gain more from a polygynist than pairing off with a single male on a resource-poor area
- monogamous females had only slightly higher reproductive success than polygynous females
95
How do blackbirds exhibit polygyny threshold?
- females only choose unmated males
- by adding additional nests, females chose sites with extra nesting sites even if there was another female present
96
How do manakins support lek polygyny?
preferred males have the center position and engage in more aggressive displays
97
How do topi anelopes support lek polygyny?
older males occupy center position and can mate more
98
Why do species form leks? (3)
leks evolved only when other reproductive tactics
don’t pay off for males.
Female resources are not clustered.
Instead, males display their goods to choosy females that come to
the leks to inspect them
99
What organisms support the hotspot hypothesis? (3)
sage grouse
fallow deer
peacocks
100
When does the hotspot hypothesis not work for lekking?
for ungulates where ovulating females leave customary foraging ranges to visit males that are a
considerable distance away, in order to compare males.
101
How do barking treefrogs disprove hotspot hypothesis?
The more chorusing males at a pond, the more receptive females
show up.
Preventing males from coming to those ponds do not reduce the
numbers of females arriving.
