This multi-author volume provides both a conceptual context and an instruction in methods for many aspects of sex ratio research. The book discusses theory, statistical analysis, and genetics, as well as research in one of a wide spectrum of animal, plant, and microbial taxa. Sex Ratios: Concepts and Research Methods is primarily intended for graduate and professional behavioral and evolutionary ecologists in this field, but it will also be useful to biologists building evolutionary models, and researchers analyzing data involving proportions or comparisons across phylogenetically related species.