Mouthparts of the first instar larva of Manduca sexta are characterized by the spigot, a tubular protruding structure through which the silk is discharged. In later instars this structure is reduced, and a new study in Insect Systematics and Diversity models in new detail the caterpillar’s first instar silk-producing anatomy and subsequent loss of that capability as it molts to later instars. (Image courtesy of István Mikó, Ph.D.)