Factors influencing the optimum sex ratio in a structured population
type: Item
instance of: scholarly article
title: Factors influencing the optimum sex ratio in a structured population
zbMATH Open document ID: 0629.92011
DOI: 10.1016/0040-5809(88)90002-0
author: Leonard Nunney
author: Robert F. Luck
published in: Theoretical Population Biology
publication date: 1988-01-01T00:00:00Z
review text: \textit{W. D. Hamilton}, Science 156, 477-488 (1967), calculated the optimum sex-ratio strategy for a population subdivided into local mating groups. He made three important assumptions: that the females founding each group responded precisely to the number of them initiating the group; that ail broods within a group matured synchronously; and that males were incapable of dispersing between groups. We have examined the effects of relaxing each of these assumptions and obtained the following results: (1) When broods mature asynchronously the optimum sex ratio is considerably more female biased than the Hamiltonian prediction. (2) Increasing male dispersal always decreases the optimum female bias to the sex ratio, but it is of particular interest that when moderate levels of dispersal are coupled with asynchrony of brood maturation then the optimum strategy is relatively insensitive to changes in foundress number. (3) When females cannot precisely determine the number of other foundresses initiating the group then the optimum strategy is almost exactly the strategy appropriate to a group of average size. These effects can be most easily understood in terms of local parental control (LPC) of the sex ratio. Through LPC a founding female can alter the mating success of her sons by altering the sex ratio of her brood. Asynchrony in the maturation of broods within a group increases the control that a founding female has over the mating success of her sons, whereas male dispersal reduces it. We have shown that the role of LPC and the role of inbreeding, which favors a female-biased sex ratio in haplodiploid species, are independent and that their effects can be combined into a single general formula \[ r=(1-(r^ 2/z^ 2)E(\partial z/\partial r))/(1+I). \] The concept of LPC can also be used to interpret two factors which have been proposed to select for the Hamiltonian sex ratios: local mate competition is LPC acting through sons; and sib mating is LPC acting through daughter…
Mathematics Subject Classification ID: 92D10
Mathematics Subject Classification ID: 92D25
Mathematics Subject Classification ID: 92D15
zbMATH DE Number: 4025220
zbMATH Keywords: population genetics
zbMATH Keywords: structured population
zbMATH Keywords: optimum sex-ratio strategy
zbMATH Keywords: local mating groups
zbMATH Keywords: dispersal
zbMATH Keywords: asynchrony of brood maturation
zbMATH Keywords: local parental control
zbMATH Keywords: mating success
zbMATH Keywords: LPC
zbMATH Keywords: inbreeding
zbMATH Keywords: female-biased sex ratio
zbMATH Keywords: haplodiploid species
zbMATH Keywords: local mate competition
zbMATH Keywords: sib mating
MaRDI profile type: Publication
Wikidata QID: Q44006953
full work available at URL: 0040-5809(88)90002-0
OpenAlex ID: W2057776450
cites work: Hierarchical selection theory and sex ratios I. General solutions for structured populations
cites work: A theory of group selection.
description: scientific article; zbMATH DE number 4025220