Stratification of fruit-feeding nymphalid butterflies in a Costa Rican rain forest

Paired traps showed that fruit-feeding nymphalid butter flies in the subfamilies Nymphalinae, Charaxinae, Morphinae and Satyrinae are stratified between the canopy and the understory by species composition, and abundance, size, and color pattern. 2) Short wing lengths and uniform underside patterns are found in the canopy, whereas long wing lengths and underside patterns bearing eyespots are found in the understory. 3) Wing length and color pattern cannot be separated from taxonomic affinity, and hence, these butterflies stratify by subfamily: Charaxinae and Nymphalinae in the canopy, Morphinae and Satyrinae in the understory. 4) A general model is presented to explain the apparent breakdown of stratification along forest edges and how light levels act as barriers to maintain insect stratification.