Parental expenditure and offspring sex ratios in the dioecious plant Silene alba

Article Abstract:

The factors influencing sex ratio selectivity in Silene alba are determined by investigating the impact of sex ratio bias on parental expenditure in both sexes. The equivalent seed mass of both sexes in different families and the nonexisting seed sex-mass relationship, prove that there are no variations in the cost of raising both sexes. Sex ratio discrimination also starts prior to the termination of the parental provision to the seeds. These results contradict the conditions predicted to prefer 1:1 sex ratio in natural selection.

Perennials, Perennial plants

---

Natural selection and the sex ratio: Fisher's sources

Article Abstract:

RA Fisher's 'The Genetical Theory of Natural Selection' proved that sex ratio and other population characteristics are determined through individual natural selection. Fisher's ideas, however, were found to be influenced by Charles Darwin's arguments in the second edition of 'The Descent of Man' and JA Cobb's paper 'The problem of the sex-ratio.' Fisher was further criticized for failing to trace the beginnings of his ideas on natural selection.

Works, Darwin, Charles, Fisher, Ronald Aylmer

---

Population structure influences sex ratio evolution in a gynodioecious plant

Article Abstract:

Research is presented on plant gynodioecy, or the reproduction structure in which hermaphrodites and females co-occur, and the influence of plant population dynamics on plant sex differentiation. It is posited that the evolution of sex ratio reflects a species' metapopulation context; in the case of test species Silene vulgaris, sex ratio results from its existence as a weedy species that has modified itself to a disturbed habitat.

United States, Statistical Data Included, Environmental aspects, Plant communities, Sex in plants, Sex (Botany), Vegetation dynamics, Sex differentiation, Plant populations, Hermaphroditism, Gynogenesis

Similar abstracts:

• Abstracts: Crustal structure and magmatism of North Atlantic continental margins. Carboniferous magmatism in the Iapetus convergence zone: evidence from deep seismic reflection profiles
• Abstracts: Upper mantle reflector structure and origin beneath the Scottish Caledonides. Does the Great Glen fault really disrupt Moho and upper mantle structure?
• Abstracts: Basement reactivation in a sub-Andean foreland flexural bulge: The Pantanal wetland, SW Brazil. Crustal shortening and Eocene extension in the southeastern Canadian Cordillera: some thermal and rheological considerations
• Abstracts: Testing the marine and continental fossil records: comment and reply. Middle Cretaceous reef collapse linked to ocean heat transport: comment and reply

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.