title: Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy.
abstract: There are three sex ratio strategies (SRS) in nature-male-biased sex ratio, female-biased sex ratio and, equal sex ratio. It was R. A. Fisher who first explained why most species in nature display a sex ratio of ½. Consequent SRS theories such as Hamilton's local mate competition (LMC) and Clark's local resource competition (LRC) separately explained the observed deviations from the seemingly universal 1:1 ratio. However, to the best of our knowledge, there is not yet a unified theory that accounts for the mechanisms of the three SRS. Here, we introduce the price elasticity theory in economics to define sex ratio elasticity (SRE), and present an analytical model that derives three SRSs based on the following assumption: simultaneously existing competitions for both resources A and resources B influence the level of SRE in both sexes differently. Consequently, it is the difference (between two sexes) in the level of their sex ratio elasticity that leads to three different SRS. Our analytical results demonstrate that the elasticity-based model not only reveals a highly plausible mechanism that explains the evolution of SRS in nature, but also offers a novel framework for unifying two major classical theories (i.e., LMC &LRC) in the field of SRS research.
authors.affiliation: Institute of Mathematics and Information Science, Baoji University of Arts and Sciences, Baoji, Shaanxi, China.|Computational Biology and Medical Ecology Lab, Theoretical and Experimental Ecology Lab, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Science, Kunming, Yunnan, China.
authors.forename: Yaqiang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Center for Ecological and Environmental Sciences, Key Laboratory for Space Bioscience &Biotechnology, Northwestern Polytechnical University, Xi'an, Shaanxi, China.
authors.forename: Ruiwu
authors.initials: R
authors.lastname: Wang
authors.affiliation: School of Mathematics and Statistics, Yunnan University, Kunming, Yunnan, China.
authors.forename: Yaotang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Computational Biology and Medical Ecology Lab, Theoretical and Experimental Ecology Lab, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Science, Kunming, Yunnan, China.
authors.forename: Zhanshan
authors.initials: Z
authors.lastname: Sam Ma
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D008954:Models, Biological; D012744:Sex Ratio