SR11: Green+ Hatchwell 2016- helper effort variation in cooperatively breeding birds

Question 1

what does the inclusive fitness theory predict cooperative investment should positively correlate with?

Answer 1

relatedness of helpers to recipients of their care

Question 2

what was the comparative analysis of?

Answer 2

helper investment in 36 cooperatively breeding bird species

Question 3

what increases as mean relatedness between helpers and recipients increases

Answer 3

species specific helper contributions

Question 4

what fact did the study support?

Answer 4

that variation in helping behaviour in cooperatively breeding birds is consistent with hamilton’s rule

Question 5

in vertebrate cooperative systems what are social groups mainly comprised of?

Answer 5

close relatives

Question 6

what is more likely to evolve in species with low promiscuity?

Answer 6

caring for others offspring

Question 7

what does hamilton’s rule predict?

Answer 7

conditions under which kin selected cooperation should evolve with investment in cooperation greater as relatedness between actor and recipient increases

Question 8

when are potential helpers more likely to help?

Answer 8

when recipients close kin

Question 9

when caring for young what is the trade off?

Answer 9

between fitness gained from current investment against costs of investment for future fitness gain

Question 10

what does comparing helper effort across species show?

Answer 10

that helper investment increases with kinship to the brood

Question 11

what was the mean provisioning rate of helpers expressed as a proportion of?

Answer 11

provisioning rate of parents

Question 12

when should helper investment be high?

Answer 12

when probability of future independent breeding is low

Question 13

if most individuals in a population can breed then what does this mean?

Answer 13

low constraints on reproduction and few pairs have helpers

Question 14

what should carers adjust their care according to

Answer 14

the number of carers at a nest

Question 15

typically what sex are the helpers?

Answer 15

male due to females dispersing and reproducing outside their natal group so the sex ratio is often male biased

Question 16

how many species in how many families was data collected from?

Answer 16

36 species in 23 families

Question 17

in all species what did care provided by helper increase with?

Answer 17

kinship to the brood

Question 18

what % did helper effort approach when r was close to 0.5? and what does this support?

Answer 18

100%

supports inclusive fitness theory

Question 19

when should kin discrimination only be selected for?

Answer 19

when risk to caring for non kin

Question 20

what may happen if costs are low and indirect benefits are high?

Answer 20

lots of helpers may care for non kin

Question 21

when did helper effort decrease?

Answer 21

with proportion of male helpers

Question 22

when do both sexes work harder relative to parental effort?

Answer 22

when more female biased helper sex ratios?

Question 23

if females remain in their natal territory what does it mean?

Answer 23

higher relatedness in groups which may select for more provisioning effort by helpers

Question 24

what does helper contributions to brood care increase with?

Answer 24

relatedness of helpers to recipients

Question 25

what is a direct fitness benefit that may arise?

Answer 25

inheritance of the breeding territory

Question 26

what does the optimal strategy for investment depend on?

Answer 26

investment of others in the same brood

Question 27

how does it provide evidence for hamiltons rule?

Answer 27

close relatives provide more care

Question 28

in cooperatively breeding species in some cases what do helpers assume most?

Answer 28

the responsibility for brood care

Question 29

what was it testing?

Answer 29

if variation in helper contribution is predicted by inclusive fitness theory

Question 30

what will happen when constraints on successful independent reproduction are high and an example

Answer 30

most pairs will have helpers such as the white winged chough

Question 31

what is the result for the females when helpers are typically male

Answer 31

higher probability of dispersing and of independent reproduction outside the natal group

Question 32

what findings from other studies does it support?

Answer 32

that there is consistent discrimination in favour of kin by helpers