The Senses of Butterflies: Taste and Smell

Chemoreceptors: Specialized sensory nerve cells or sense organs that respond to chemical stimuli. Etymology: Gk, chemeia + L, recipere, to receive

Butterflies experience taste and smell in much the same way as humans, through the use of chemoreceptors on the body. In humans chemoreceptors can be found on our tongues in the form of taste buds and in specialized sensory cells found in our noses.

The sense of smell in butterflies is experience mainly through their antenna. Butterfly and moth antennae are covered in densely packed chemoreceptors. Depending upon the species of butterfly, these chemoreceptors are utilized to smell the pheromones of the opposite sex of their species so butterflies can find each other to mate. Chemoreceptors may also smell the honey scent of flower nectar and the scents of other food sources.

Tasting with your feet: The butterfly body is covered in chemoreceptors. On the butterfly tarsus (foot) contact chemoreceptors can sense the presence of dissolved sugars like those found in flower nectar. When the taste sensors are activated, the butterfly will uncoil its proboscis to consume the nectar it has detected. By just landing on a surface, a butterfly can taste if something to eat is available.

Female butterflies have specialized chemoreceptors to help them find the right host plant. Female butterflies have tiny spines on the backs of their legs that are used to drum against a plant leaf and release juices from the plant. These juices or the plant surfaces are tested or tasted by chemoreceptors at the bases of the tiny spines and can determine if the female butterfly has found the right host plant for her eggs. Some species of butterfly like the Monarch will test a host plant with all six legs before beginning to lay eggs.

What if you experienced taste through your feet? Here at BioWorks we often ask that question of visiting school children and receive a bunch of frowns and exclamations of “Yuck!” or “Gross!” in response. We often utilize that opportunity to suggest they keep their shoes clean.