8-role of kin selection Flashcards
give 2 direct fitness benefits
- current reproduction
- increased future reproduction
in what 2 ways is future reproduction increased?
- acquisition of skills/mate/territory
- group augmentation (increased survival in larger groups)
give an indirect/kin selected fitness benefit and 2 components of this
increased fitness of relatives
- better productivity
- better survival of breeders
- what does each transition in the evolution of life on earth involve?
- what aims to understand each transition?
- what logic is used?
- cooperation
- modern social evolution theory
- IFT logic
what is eusociality?
‘true sociality’ with non reproductive/sterile castes
what is the hypothesis for why individuals join together to become mutually dependent?
high relatedness between individuals played key role in transition to sociality
according to Boomsma 2007/9 what is the monogamy hypothesis for the origin of social groups?
strict lifetime monogamy (F only mates once) results in individuals equally related to offspring + their siblings (r=0.5)
according to the monogamy hypothesis what does a small net benefit from raising siblings rather than offspring favour?
cooperation and potentially eusociality
what happens if F mates multiple times
average r to siblings decreases
what are the 2 main predictions of the monogamy hypothesis?
- all eusocial species pass through monogamy window
- multiple mating may evolve later, after specialisation
how do non social organisms become eusocial?
through cooperative transition involving relatedness which is determined by strict lifetime monogamy
what did Hughes et al 2008 discovr about eusocial linages?
all eusocial lineages have passed through an ancestral monogamy window (were once monogamous)
what did Lukas and Clutton brock 2012 find about if the monogamy hypothesis applies to mammals?
- if strong reproductive skew then high relatedness in the social group
- strong skew in coop groups, supporting monogamy hypothesis
how did cornwallis 2010 show how the monogamy hypothesis applies to birds? (3)
- no strict monogamy but was still lower in non coop species
- high r when low promiscuity in coop groups
- more promiscuity in non coop groups
what is the hypothesis for coop breeding evolution in birds?
evolved in kin groups
in hatchwells study of birds what % of families and species did cooperation occur in:
a) kin groups
b) non kin groups
a) kin: 82% families
92% species
b) non kin: 18% families
8% species
why is kinship important in the evo of coop?
creates opportunity for kin selection to operate
in Reiehl 2013 study of 213 coop breeding species what %:
- helped in family groups
- helped in groups with kin and non kin
- lived mainly with non kin
- total helped
- 55%
- 30%
- 15%
- 85%
what groups predominate among coop breeders and what are the exceptions?
kin groups
- cooperative polygamists where all individuals attempting to breed
give 2 points about kinship importance
- inbreeding avoidance reduces conflict within groups over reproduction
- kin selected helping often assumed to be important
in the white fronted bee eater why is it good to be in a large group?
successful at reproduction and more fledglings per nest