Flashcards in special reading - cooperative breeding - 1 - helping effort in bell miners Deck (6)
what is the aim of this paper?
distinguish between the only remaining hypotheses, kin selection and group augmentation, for the evolution of helping-at-the-nest in a cooperative bird
- predict an incremental increase in helping effort with genetic relatedness
what are they exploring?
- explores in detail within- and between-individual variation in nest visit rates, load sizes and prey types delivered by parents and helpers according to sex and genetic relatedness in bell miners
- also examine visit-by-visit responses of breeders and helpers to nestling begging signals of brood need
what were the results?
- proved kin selected helping – however no evidence that bell miners were more likely to help at the nests of relatives
- Bell miner helpers seemed to attend hungry broods located within their coterie as required, irrespective of helper sex or relatedness to the brood
- no sex differences were detectable in any aspect of helping, and even non-relatives provided substantial aid
what do the results mean in relation to the hypotheses being tested?
- comprehensive test for both direct and indirect fitness effects on helping- showed no direct fitness benefits for some just that the visiting rates were strongly effected by the begging rates of the chick
- suggested within coterie relatedness could explain the apparent indirect effects
what do the results mean in relation to the study of animal behaviour in general?
- Helping behaviour in bell miners appears consistent with adaptive cooperative investment in the brood, and kin-selected care by relatives