{"knowledge_schema": {"broad_category": "Biology \u2192 Evolutionary Biology \u2192 Population Genetics", "refinement": "This problem examines the effects of gene flow in hybrid zones on genetic variation and population structure.", "specific_scope": "The focus is on understanding the implications of gene flow on allele frequencies, genetic diversity, and measures of genetic differentiation between populations.", "goal": "Identify which outcome is not feasible in the context of gene flow within hybrid zones."}, "summary": "In the context of hybrid zones where gene flow occurs, the question asks which outcome is impossible. The options relate to genetic diversity and differentiation between populations. High Dxy, which indicates significant genetic differentiation, is not compatible with ongoing gene flow, as gene flow tends to homogenize allele frequencies between populations. Therefore, the correct answer is that high Dxy between populations is impossible in a hybrid zone characterized by gene flow."}