Butterflies taste with their feet. Tiny, hair-like sensors detect chemical changes in plants that may be harmful, either as food for butterfly caterpillars or nectar for adults. A female determines the safety of an egg-laying site by stamping her feet on the foliage to release any defensive chemicals.
In addition to tasting with their feet, butterflies have two additional ways to experience touch and smell: a proboscis and antennae. A proboscis is a long, curled tongue that is similar to a coiled garden hose when not in use, but when feeding on sap and nectar, it resembles a straw. Butterfly antennae assist in locating appropriate food sources by touching them for a chemical reaction of warning and for smelling the fragrance, which also alerts them to potential dangers.