conflict within families

Question 1

intersexual conflict:

Answer 1

conflict between male and females

Question 2

intersexual conflict: Langurs (and lions)

Answer 2

• male competition to reproduce is intense, infanticide may occur
• matrilineal societies (related F and 1 single male)
• 4 males ruled over 5 year period = 83% of infants died
• male kills dependent offspring and mate w female

Question 3

conflict & suppression over reproduction in cooperative breeders:

Answer 3

• Acorn Woodpeckers
• Females are joint nesters
• females in nests often close relatives
• 38% of eggs laid in joint nests are destroyed, f from same breeding group
• females destroy eggs if they are still yet to lay
• 10% of eggs laid by joint-nesters are runt eggs, that are laid early when risk of egg destruction is high

Question 4

conflict over reproduction in cooperative groups: Meerkats

Answer 4

• 1 single dom M and single dom F
• • m&f subordinates also
• thought dom would only breed (3/yr), but subordinate do also (1/yr).
• sub F pregnancies and litters more likely to fail, as are chased and harassed by dom f and litter is often killed by dom or others
• dom also evict subordinates when dom pregnant
• WHY
• -limited resources and subordinate litter costly to dom as restrict amount of food they can receive

Question 5

conflict over reproduction in eusocial insects:

Answer 5

• in some social insects workers retain functional ovaries
• haplodiploid allows them to produce sons
• SO workers should lay eggs to produce sons
  as 0.375>0.25
• BUT this depends on mating fre of queen, if queen mates multiple times so workers should prevent other workers from reproducing ‘WORKER POLICING’ as favour brothers (0.25) or nephews (0.125)

-WHY MONOGAMY IS IMPORTANT IN EUSOCIALITY

-seen in honeybees RATNIEKS & VISSCHER 1989
and seen across species of WASPS and BEES

Question 6

haploidiploidy=

• worker - son
• worker - worker
• worker - nephew
• worker - brother

Answer 6

-worker - son = 0.5
- workers related by 0.75
- worker - nephew = 0.375
- worker - brother = 0.25
—SO workers should lay eggs to produce sons
as 0.375>0.25

Question 7

worker reproduction depends on

Answer 7

mating frequency

Question 8

policing in eusocial systems enforces

Answer 8

altruism

Question 9

Loope 2015 Dolichovespula wasps Queen killing

Answer 9

queen mates w one male, workers want nephews (0.375) than brothers (0.25)

queen mates w lots, workers want brothers (0.25) not nephews (0.175)
—SO in monogamous colonies, QUEEN is killed

Question 10

conflict over helping cooperative breeding groups: White-fronted bee-eater: HARRASSMENT TO RECRUIT HELPERS

Answer 10

• White-fronted bee-eater
• extends families, multiple breeding pairs
• harassment (chasing and interference in courtship, block nest access/ egg removal)
• 34% of harassed, helped at nest of harassers
  HARRASSMENT TO RECRUIT HELPERS
• helpers allow pair to breed more offspring, raising close relatives, helping has same pay off as breeding
• more likely to help if they are closely related as benefits them more

Question 11

conflict over inbreeding:

Answer 11

KOENIG ET AL 1998
- Acorn woodpecker
- potential for this if a breeder dies and if they’re replaced by a related helper
- just 5% of cases result in incest
- AVOID:
if M dies, helper commonly leaves, sometimes breeder leaves
- to decide who leaves, massive conflict can last long time (3+years), during this time, no breeding!

Question 12

extent of conflict often depends on

Answer 12

relatedness