Chapter 3

Question 1

Why are social groups Darwinian puzzles, as seen in wolves and bugs?

Answer 1

why do wolves live in packs, even though some individuals may never reproduce themselves

• leaf-footed coreid bugs cluster together; may face food competition and disease contraction

Question 2

What does cost-benefit analysis suggest about group living?

Answer 2

solitary may be mroe beneficial

Question 3

What are the pros and cons of cliff swallow nesting?

Answer 3

cooperative foraging

larger colonies have more parasites- leads to underdeveloped offspring

Question 4

What is cooperation, and result for the helper?

Answer 4

helps each other right now
helper- direct fitness immediately
receiver- direct fitness

Question 5

What is postponed cooperation, and result for the helper?

Answer 5

helper eventually gains access to resource controlled by receiver because of prior help
helper- direct fitness after delay
receiver- direct fitness

Question 6

What is reciprocity, and result of the helper?

Answer 6

Receiver directly pays helper back for its prior aid
helper- direct fitness after delay
receiver- direct fitness

Question 7

What is maladaptive altruism, and result of the helper?

Answer 7

Helper sacrifices its lifetime inclusive fitness to help receiver
helper- loses inclusive fitness
receiver- direct fitness

Question 8

What is adaptive altruism, and the result for the helper?

Answer 8

initial direct fitness sacrificed by helper leads to indirect fitness gains for helper
helper-gains indirect fitness
receiver- direct fitness

Question 9

What is spite, and the result for the helper?

Answer 9

helper reduces reproductive success in order to harm receiver
helper-loses inclusive fitness
receiver- loses inclusive fitness

Question 10

What is deceit and manipulation, and result?

Answer 10

receiver exploits or manipulates helper to harm helper but benefit receiver
helper- loses inclusive fitness
receiver- gains inclusive fitness

Question 11

How are social interactions categorized?

Answer 11

based on cost and benefit

Question 12

What is cooperation, and two examples?

Answer 12

when both individuals benefit from helping each other
cooperative foraging mobbing calls (predator detection warning)

Question 13

How do paper wasps cooperate?

Answer 13

by helping queen and others (even when unrelated), they have a chance of inheriting the nest: higher fitness than solitary wasps

Question 14

How do Lazuli Buntings cooperate?

Answer 14

bright males tolerate dull: mates with dull male’s females
dull male: can stay in territory but needs to care unrelated young
intermediate colors: chased out

Question 15

How do Long-tailed Manakins exhibit cooperation?

Answer 15

male pairs to court

one male will reproduce

if courting male disappears, beata male is next in line to reproduce

Question 16

What is reciprocal altruism, and an example?

Answer 16

compensation is directly repaid from helped individuals; doesn’t sacrifice fitness

grooming in primates

Question 17

How do flycatchers exhibit reciprocity?

Answer 17

pairs help other pairs mob predators if they were helped

Question 18

What is the prisoner’s dilemma?

Answer 18

Cheaters are likely in a system, and would reduce fitness of helping

Question 19

How can reciprocity evolve? (2)

Answer 19

gains can pile and become profitable in multiple interactions

individuals can forgive occasional defection to encourage long-term relationships with additional payoffs

Question 20

How do vampire bats exhibit reciprocity?

Answer 20

successful hunters can obtain a lot of blood; can choose to give up a small amount to failed hunters

recipient’s benefit is high, because they starve in 3 days

those who give are better off, as they may be guaranteeing help later on

Question 21

How did Belding’s ground squirrels exhibit reciprocity?

Answer 21

squirrels warn others when they detect a predator by whistling
calling squirrels are tracked easier

Question 22

How did Belding’s ground squirrel and relatedness correlate?

Answer 22

adult females live near offspring and more likely to give an alarm- direct fitness
females with nondescendant kins are more likely to call than those without sisters, aunts, and nieces - indirect fitness

Question 23

How do kingfishers help?

Answer 23

year-old males that can’t find mates become primary helper

primary helpers feed mothers and nestlings and attack enemies

primary helpers sacrifice future reproduction in year 2 in exchange for increased number of nondescendant kin in year 1

Question 24

How do kingfishers act as secondary helpers?

Answer 24

secondary helpers help unrelated nesting pairs

primary helpers do the most work, and have the lowest survival rate

only 2/3 of primary find mates, while 91% of secondary helpers find mate

secondary helpers can mate with the nest mother

Question 25

How can kingfishers act as delayers?

Answer 25

wait until the next year to reproduce

Question 26

How can helping be a nonadaptive side effect of other fitness-enhancing traits? (3)

Answer 26

may be adaptive for young adults delay dispersal from natal territory parental behavior may be triggered by begging nestlings selection cannot eliminate helper tendency without destroying capacity to care for its own

Question 27

How did Jay species support the fact that hormones may cause helping?

Answer 27

non-helpers have higher levels of prolactin in breeding individuals, which is thought to promote parental care helpers have high levels of prolactin before young is born

Question 28

What kind of fitness does helping provide? (2)

Answer 28

inheriting territory is direct fitness indirect fitness by helping parents rear more offsprings

Question 29

How do carrion crows exhibit helping?

Answer 29

kin that are helpers get an indirect fitness benefit by increasing number of full and half siblings that fledge the nest

Question 30

How do fairy wrens exhibit helping?

Answer 30

helpers may increase indirect fitness by reducing parent’s work mother can make lighter eggs, so they can produce more and live longer

Question 31

How does territory quality induce helping in Scrub Jays?

Answer 31

when few opening for dispersing young is available, helping sibling and parents may be the most adaptive

Question 32

Non-adaptive by-product hypothesis of helping

Answer 32

helpers might benefit by being on good habitat when not breeding

Question 33

How do Seychelles warblers exhibit the non-adaptive by-product hypothesis?

Answer 33

less helpers in a vacant area lack of habitat leads to more helping young helpers in good territories more likely to survive and increase parent output if territory wasn't good, helpers leave

Question 34

How do white-fronted bee-eaters exhibit non-adaptive by-product hypothesis?

Answer 34

nests in loose colonies females can help or not reproduce, or reproduce older, unpaired dominant males may get females to leave family if they are helpers female helpers avoid younger males fathers of the females would harass her if she runs off with older males

Question 35

How do naked mole rats exhibit non-adapative by-product hypothesis?

Answer 35

colonies of one queen and several kings queen polices colony, causing sterility in workers suboordinates can leave, but is risky

Question 36

How is altruism exhibited in vertebrates? (2)

Answer 36

most can still reproduce and help for a limited time often facultative, not obligate

Question 37

How does promiscuity affect helping?

Answer 37

promiscuous birds species are less likely to display cooperative breeding than monogamous ones

Question 38

How do fairy wrens go against the promiscuity-helping idea?

Answer 38

some helpers are unrelated