1. The Significance of Asymmetrical Sexual Isolation. - The Kaneshiro Models. - The WatanabeKawanishi Models. - Other Models. - Discussion. - References. - 2. Comments on The Significance of Asymmetrical Sexual Isolation. - References. - 3. The Significance of Asymmetrical Sexual Isolation and the Formation of New Species. - Other Models of Asymmetrical Sexual Isolation. - Empirical Data in Support of the Kaneshiro Model. - Male Choice or Female Choice?. - Mating Propensity and Sex Drive. - The Direction of Evolution in Hawaiian Drosophila. - Mating Asymmetries and Speciation. - Concluding Remarks. - References. - DNA Hybridization and Avian Systematics: Introduction. - 4. DNA Hybridization and Avian Phylogenetics. - From Organisms to Distances: The Data. - From DNA Distances to Trees: The Analytical Methods. - Discussion and Interpretation. - References. - 5. DNA Hybridization and Avian Phylogenetics: Reply to Cracraft. - References. - 6. DNA Evolutionary Implications of Phenotypic Plasticity in Plants. - The Nature of Phenotypic Plasticity. - Analysis of Phenotypic Expression. - The Genotypic Basis of Plasticity. - The Expression of Plasticity. - Evolutionary Responses to Environmental Heterogeneity. - What Is Fitness in Plants?. - Conclusions. - References. - 7. Deuterostome Monophyly and Phylogeny. - Deuterostomes. - Echinoderms. - Hemichordates. - Urochordates. - Cephalochordates. - Craniates. - Character Analysis. - Analysis and Comments. - Resumé. - Abbreviations. - References. - 8. Arvicolid Data (Arvicolidae Rodentia) and Evolutionary Concepts. - Morphological Data. - Morphological Data and Arvicolid Phylogeny. - Chromosomal Data. - Biochemical Data. - Arvicolid Data and Speciation. - Arvicolid Data and Phyletic Gradualism. - Arvicolid Data and Stasis. - How Often? Relative Importance of AllopatricSpeciation Phyletic Gradualism and Stasis among Arvicolids. - Discussion: Arvicolid Data and Evolutionary Concepts. - Conclusion. - Summary. - References. - 9. Evolutionary Rates under Environmental Stress. - Stress and Natural Selection. - Variation under Stress. - Evolutionary Rates. - Conclusions. - Summary. - References. - 10. Cricket Life Cycles. - Life Cycle Types. - Egg Stage. - Nymphal Stage. - Adult Stage. - Geographical Adaptations. - Life Cycle and Speciation. - References. Language: English