Illicit minor

Biological Parallel

'All birds can fly. All birds are animals. Therefore, all animals can fly.' The minor term (animals) is distributed in the conclusion but not the premise. Biological example: 'All observed species in this ecosystem are generalists. All observed species are present. Therefore, all present species are generalists.' The fallacy assumes complete sampling when sampling is partial. Bats accounting for 20% of mammal species are almost entirely missed by daytime surveys—observing zero bats doesn't mean bats are absent. Fungi represent 90% of forest biomass yet most species lack fruiting bodies visible to surface surveys—observing 50 mushroom species doesn't reveal the 950 mycorrhizal species underground. Moths outnumber butterflies 10:1 but daytime transects capture only butterflies—concluding 'this meadow has no Lepidoptera specialists' from butterfly-only data commits the illicit minor. Specialists often evade detection through nocturnal habits, cryptic behavior, or subsurface life. The error: treating observed subset as complete set.