Tiger swallowtail genome gives clues to insect’s stinky defense

Eastern tiger swallowtail (Papilio glaucus) caterpillar

As caterpillars, Eastern tiger swallowtails have a forked organ on their heads that emits smelly compounds to deter predators. A look at the insect’s genome explains how it may have evolved this stinky biological warfare. 

Edith Smith/Shady Oak Butterfly Farm

Eastern tiger swallowtail
Eastern tiger swallowtail butterfly Bryan Reynolds/Butterflies of the World Foundation
Clues within the genetic code of the Eastern tiger swallowtail butterfly ( Papilio glaucus ) explain how it developed a smelly defense against predators.

As caterpillars, swallowtails have a forked organ on their heads that pumps out foul-smelling compounds called terpenes. Sequencing the swallowtail genome revealed extra copies of the genes that the scientists believe are responsible for making enzymes that assemble terpenes.

This and other insights into swallowtail genetics appear February 12 in Cell Reports.

Use up and down arrow keys to explore.Use right arrow key to move into the list.Use left arrow key to move back to the parent list.Use tab key to enter the current list item.Use escape to exit the menu.Use the Shift key with the Tab key to tab back to the search input.