Evolutionary Biology,ofwhichthisisthetwenty-thirdvolume,continues toofferitsreadersawiderangeoforiginalarticles,reviews,andcom mentariesonevolution,inthebroadestsenseofthatterm. Thetopicsof thereviewsrangefromanthropology,molecularevolution,andpaleo biologytoprinciplesofsystematics. Inrecentvolumes,abroadspectrumofarticleshaveappearedon suchsubjectsasbiochemicalsystematics,comparativemorphologyand embryology,evolutionaryecology,biogeography,andpaleobiology. We havealsoattemptedtoprovideaforumforconflictingideas. Articlessuch asthese,oftentoolongforstandardjournals,arethematerialfor Evo lutionary Biology. Theeditorscontinuetosolicitmanuscriptsonaninternationalscale inanefforttoseethateveryoneofthemanyfacetsofbiologicalevolution iscovered. Manuscriptsshouldbesenttoeitherofthefollowing:Max K. Hecht,DepartmentofBiology,QueensCollegeoftheCityUniversity ofNewYork,Flushing,NewYork11367,orBruceWallace,Department ofBiology,VirginiaPolytechnicInstituteandStateUniversity,Blacks burg,Virginia24061. TheeditorswishtocongratulateDr. GhilleanT. Pranceonhisnew appointmentatKewBotanicalGardensandthankhimforhiscollabo rativeeffortsineditingthepastninevolumes. TheEditors vII Contents 1. MaintenanceofaHereditaryVirus:TheSigmaVirusin PopulationsofItsHost, Drosophila melanogaster 1 Annie Fleuriet Introduction 1 FrenchPopulationsof Drosophila melanogaster. . . . . . . . . . . 2 PolymorphismofPopulations 2 CharacteristicsofWildStrainsoftheSigmaVirus 3 EffectsoftheInfectionuponCarriers. . . . . . . . . . . . . . . . . 7 ExperimentalPopulations. . . . . . . . . . . . . . . . . . . . . . . . . . 9 MaintenanceoftheVirusinFrenchNaturalPopulations. . . 12 GeographicalVariationofthe Drosophila-SigmaSystem 14 PolymorphismofPopulations 14 ViralCharacteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 TentativeInterpretationoftheGeographicalPatternObserved 18 OtherSystemsofVerticallyTransmittedViruses 22 ExistenceofDifferentSensitivitiestotheVirus 22 CharacteristicsoftheViruses. . . . . . . . . . . . . . . . . . 23 MaintenanceintheVectorPopulation 24 Appendix:TransmissionofStabilizedandNonstabilized Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Self-MaintenanceofStabilizedConditionthroughMaternal Lineage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 NonstabilizedCondition . . . . . . . . . . . . . . . . . . . . . . 27 References 28 2. Domestication:EvolutionaryChangeunderStress 31 M. J. Kohane and P. A. Parsons Introduction 31 EnvironmentalChangeandDomestication 33 Ix x Contents EcologicalPhenotypes 33 BehavioralPhenotypes. . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 AdaptationtoLaboratoryConditions. . . . . . . . . . . . . . . . . . . 37 ACaseStudy:DomesticationinFoxes 41 Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 References 46 3. RangeExpansionandItsGeneticConsequencesinPopulationsof theGiantToad, Bufo marinus. . . . . . . . . . . . . . . . . . . . . . . . . 49 Simon Easteal Introduction 49 TheSpreadof Bufo marinus 50 TheIntroductions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 TheAustralianRangeExpansion 52 GeneticVariationintheIntroducedPopulations. . . . . . . . . . . 58 TheData. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 GeneticVariability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 EffectivePopulationSize 62 Dispersal,GeneFlow,andNeighborhoodSize 63 TheGeneticEffectsofRangeExpansion 64 GeographicalPatternsofVariation 74 Conclusion 81 References 82 4. EvolutionbySocialSelection. . . . . . . . . . . . . . . . . . . . . . . . . . 85 Shozo Yokoyama Introduction 85 ConceptofSocialSelection. . . . . . . . . . . . . . . . . . . . . . . . . . 86 EvidenceforSocialSelection ;. . . . . . . . . . . . . . 88 MultipleNeurofibromatosis 88 HuntingtonDisease 89 MentalReta
