'Over-ripeness ovopathy, sex ratio increase and sex ratio reversal a challenging hypothesis for sex ratio modulation': An alternative interpretation

Sex Ratio Elasticity Influences the Selection of Sex Ratio Strategy

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 u...

Sexuality: Sex Ratio and Sex Expression

Sex ratio, sex change, and natural selection.

We describe the analogy between the theory of natural selection on sex ratio in newborn gonochores (which will not change sex), and on the age of sex change in sequential hermaphrodites (which are all born into one sex and change to the other later on). We also discuss the conditions under which natural selection favors sequential hermaphrodites over gonochores and vice versa. We show that, in ...

Brith Sex Ratio and Pregnancy Outcomes after Bam Earthquake

Background and Objectives: Brith sex ratio could be affected by several factors such as stress due to natural disasters like earthquake. This study was performed to determine the sex ratio and the perinatal outcomes after Bam earthquake. Materials and Methods: This case-control study was designed in two sections for the evaluation of earthquake effects on brith sex ratio and the perinatal outc...

Sex ratio under conditional sex expression.

We present a model to show that, when sex depends on environment rather than genotype, the sex expressed under relatively unfavorable conditions will be more abundant. This result refers to numbers of males and females in the population. By contrast, no clear prediction can be made about the allocation of resources to the two sexes. The model is constructed to highlight the logical relationship...