This study examined the interplay of taxonomic and contextual knowledge in cross-classification by assessing the interaction of taxonomic and ecological knowledge in folk biology. Stimuli were pairs of animal species in which the presence or absence of taxonomic and ecological relations was manipulated orthogonally. Participants judged whether each pair was related taxonomically and ecologically; we measures speed and accuracy. Presence of taxonomic relations facilitated ecological judgments for ecologically related pairs, and hindered judgments for unrelated pairs. In contrast, although ecological relations hindered taxonomic judgments for taxonomically unrelated pairs, they failed to facilitate judgments for taxonomically related pairs. These results underscore the interactive nature of different conceptual systems for cross-classified categories and suggest a disproportionally strong influence of taxonomic categories.