环境生态学---第二章 适应.ppt

KeyNotes;B1适应;Theindividualsinaspecieswhichhavethehighestfitnesswillcontributedisproportionatelytothesubsequentgenerations．Iffitnessdifferenceshaveageneticcomponent，thenthegeneticmake—upofthesubsequentgenerationswillbealtered．Thisprocessisknownasnaturalselectiononsurvivalofthefittest．;自然选择;拉马克的获得性遗传学说

;达尔文的自然选择学说;Anyheritabletraitpossessedbyanorganismwhichaidssurvivalorreproductionisanadaptation．Suchtraitsmaybephysiological，morphologicalorbehavioral．Adaptationistheresultofnaturalselection.;适应;动物的保护色、警戒色与拟态;趋同适应和趋异适应;2．趋异适应〔生态型〕

趋异适应〔divergenceadaptation〕是指亲缘关系相近的同种生物，长期生活在不同的环境条件下，形成了不同的形态结构、生理特性、适应方式和途径等。趋异适应的结果是使同一类群的生物产生多样化，以占据和适应不同的空间，减少竞争，充分利用环境资源。

植物生态型是与生活型相对应的一个概念，是指同种生物内适应于不同生态条件或区域的不同类群，它们的差异是源于基因的差异，是可遗传的。根据引起生态型分化的主导因素，可把生态型划分为气候生态型、土壤生态型和生物生态型等。;Thegenotypeisthegeneticcompositionofanindividual.Thephenotypeistheindividualorganism，aproductoftheinteractionbetweenitsgenotypeanditsenvironment．Theabilityofthephenotypetovaryduetoenvironmentalinfluencesonitsgenotypeisknownasphenotypicplasticity(e.g．humansuntan,wind-shapedplants,locustmorph(solitaryormigratory))．;请思考;生物的协同进化〔co-evolution〕;KeyNotes;B2应付环境变异;Anythingwhichtheorganismusesupordepletesisaresourceforthatorganism.Thus，nectarisaresourceforhoneybees，andlightisaresourceforallgreenplants．;Mostorganismshavetocopewithacontinuallychangingexternalenvironmentoverarangeoftimescales．SomeenvironmentalfactorsmaychangeoVersecondsorminutes(e.g．sunlightintensitywhenthereispatchycloud)whilstothers.maychangedailyorseasonallyoroveramuchlongerperiod(e.g．glaciationcycles)．;Biologicalcellscannotfunctionwithawildlyfluctuatingenvironmentandorgamsmsthereforetakestepstolimittheirinternalvariation．;Themaintenanceofarelativelyconstantinternalenvironmentbyanorganismavariableexternalenvironmentiscalled