More poetry from New Scientist, reporting on Georgetown University research into the memory of butterflies:
Seventy-eight percent of the caterpillars that were shocked directly after exposure avoided the compound in subsequent tests while still in the larval stage.
The tests were conducted inside a Y-shaped pipe that allowed the animals to choose an area smelling of ethyl acetate or of unadulterated air.
About a month later, after the caterpillars had metamorphosed, the adult moths were given the same choice test. Seventy-seven percent of them avoided the ethyl acetate pipe, suggesting that the lesson learned as a caterpillar is remembered as an adult.
“People always thought that during metamorphosis the caterpillar turns to soup and all the ingredients are rearranged into the butterfly or moth,” says [Martha] Weiss. “That clearly isn’t what happens. Parts of the brain are retained that allow memories to persist through this very dramatic transition.”
They are less ephemeral than they appear.