Moths Smell With Their Wings

A German study published in the Journal of Experimental Biology  found that tobacco hawkmoth (Manduca sexta) wings can detect specific odors floating through the air. The scientists gently snipped the edges from the moth’s wings and examined them with a scanning electron microscope to identify specialized porous hairs, which are the hallmarks of scent sensors.

To determine if the rest of the wing could also sense odors, the scientists blew puffs of different aromas onto the wings with the edges trimmed off. Fruity, floral and putrid scents were tested, but only two nitrogen-containing compounds—pyrrolidine and piperidine—produced strong responses. These fetid smells are found on the leaves of nightshade plants, where tobacco hawkmoths lay their eggs. The researchers concluded that the specialized porous sensory hairs were distributed across the wing surface, not just along the edges, and the strength of the reaction changed relative to how close the puff was to the wings.