Lecture 15- Sex allocation conflict in eusocial species

Question 1

haplodiploidy

Answer 1

reproductive system where males are haploid and females are diploid, so fertilisation creates females

Question 2

haplodiploid sibling relationships

Answer 2

sister-sister is 0.75, sister-brother is 0.25

Question 3

optimal sex allocation for queens vs workers

Answer 3

queens- 1:1 preferred
workers- 3:1 preferred, as relatedness is 3x higher for females

Question 4

what does the average sex ratio seem to be for ants

Answer 4

3:1- suggests workers are ‘winning’ the conflict- but there is a decent amount of variation

Question 5

how might relatedness impact sex ratio

Answer 5

in multiple mating systems, a sex ratio may not be favoured as relatedness becomes equal because of different fathers

Question 6

split sex ratio theory

Answer 6

different colonies within a population will have different optimal production of males and females, based somewhat on their mating system (multiple/single)

Question 7

meunier et al. 2008 findings

Answer 7

21% of variation in sex ratio can be explained by relatedness asymmetry

Question 8

how can workers manipulate sex ratio

Answer 8

counting number of matings, track ratio via hydrocarbon profile, can select and destroy males

Question 9

example of winning sex allocation conflict being costly

Answer 9

producing too many queens- can be bad for the colony overall at a single mating, but generally benefits outweigh this

Question 10

2 other potential reasons for sex ratio differences

Answer 10

queen replacement- queen dies and is replaced by a daughter, which changes relatedness, making males more related than females to the queen
multiple queens- again makes workers more related, can reduce ideal sex ratio