12: eusociality Flashcards
(36 cards)
what are the 3 main orders with eusocial systems ?
hymenoptera
isoptera
homoptera
within hymenoptera how many species are eusocial? (3)
bees: 1,000
wasps: 800
ant: 9,500/all
in isoptera how many species are eusocial?
termites: 2,000
in homoptera what species is eusocial?
aphids
what are the 3 main features of eusocial species?
- cooperative brood care (non parents help raise brood)
- sterile castes
- overlapping generations (workers raise subsequent broods)
how many total species of social insects? - how many birds and mammals?
14,000
birds: 10,000
mammals: 4,000
how many ants in the driver ant colony?
22 million
in the brazilian rainforest what % of insect and animal biomass is eusociall?
insect: 70-80%
animal: 33%
what is an example of sophisticated communication in eusocial species?
waggle dance
what is the ant myrmica rubra life cycle? (6)
- queen founds nest
- sterile workers produced
- 9 years for colony to be large enough
- after 9 years winged females and males produced
- nuptial flight and mating
- males die and females find a nest
list the 2 hypotheses for why eusociality evolved
- staying at home/subsocial
- sharing a nest/ parasocial
what is the ecology for how eusociality evolved by the staying at home hypothesis? (4)
- ancestors are solitary parasitoids
- advantage to nest guarding by females against parasites
- if enough predation pressure young stay and help mother defend and build nest
- will stay at home and never breed
what is the genetic predisposition for how eusociality evolved by the staying at home hypothesis? (3)
- for daughters at home raising full siblings (r=0.5) is the same as raising offspring (r= 0.5)
- for queen producing offspring (0.5) is better that grand offspring (0.25)
- queen should prefer daughters to stay as workers
what is the ecology for how eusociality evolved by the sharing a nest hypothesis? (4)
- cooperating sisters build nests close together
- cooperative defence but separate reproduction
- one female dominates reproduction
- young females become workers
what is the genetic predisposition for how eusociality evolved by the staying at home hypothesis? (3)
- for cooperative sisters there is benefit to raising dominants offspring
- this may outweigh benefit of breeding alone if it is risky
- relatedness ensures non reproductive female benefits from queens reproduction
what is an example of a species that fits with the stay at home hypothesis?
subsocial halictine bees
what is an example of 2 species that fit with the sharing a nest hypothesis?
polistes
stenogastrine waps
what did W.D Hamilton say about haplodiploidy?
it predisposes hymenoptera to evolve sterile castes
what are features of M and F in haplodiploidy?
M: from unfertilised eggs, haploid and form gametes without meiosis so all sperm identical
F: from fertilised eggs, diploid and form gametes with meiosis
where do sons and daughters receive their genes in terms of mother and father?
- sons: only from mother
- daughters: identical genes from father and other half from diploid mother
in the sister-sister pedigree what is the relatedness
a) via mother
b) via father
c) total
a) 0.5 X 0.5 =0.25
b) 0.5 X 1 = 0.5
c) 0.25 + 0.5= 0.75
in the sister-brother pedigree what is the relatedness
a) via mother
b) via father
c) total
a) 0.5 X 0.5 =0.25
b) 0.5 X 0 = 0
c) 0.25
in the brother-sister pedigree what is the relatedness
a) via mother
b) via father
c) total
a) 1 X 0.5 =0.5
b) 0.5 X 0 = 0
c) 0.5
what is the genetic relatedness between female and
a) mother
b) father
c) sister
d) brother
e) son
f) daughter
a) 0.5
b) 0.5
c) 0.75
d) 0.25
e) 0.5
f) 0.5
