Which is NOT a valid explanation for butterfly decline from road construction?
Roads fragment butterfly habitat, create edges, alter vegetation and microclimate, and change dispersal among patches. Road openings usually increase rather than reduce sunlight at the immediate edge, so 'loss of sunlight penetration' is not a general mechanistic explanation for decline and fits the keyed exclusion. Microhabitat fragmentation is well established, and colonisation by gap-associated species can change community composition. Claims about movement and genetic diversity require careful directionality because increased gene flow ordinarily preserves diversity. Climate, nutrients, di
Ref: Ecology: From Individuals to Ecosystems, Begon et al., 5th Ed., Ch. 17-19
