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. Specificity, Figure'2:' Host'+'Microbiota' IMMUNITY( Defence'against'pathogens' Tolerance'of'resident'microbes' DEVELOPMENT( Epithelium'renewal' Tissue'specializaCon' e.g

!. Homogamy, Symbiont'coevoluCon' SymbiontEmediated'incompaCbiliCes' ' ! Hybrid"performance,"hybrid"sterility" DiversificaMon( SpeciaMon( Host, POST.MATING(ISOLATION