By Susan Milius
Caterpillars way too immature for actual sex turn out to detect and take an interest in adult sex pheromones.
Caterpillars of the cotton leafworm moth (Spodoptera littoralis) don’t have working sex organs. They’re just long, black-green larvae eating as much as they can before transforming into the completely different body shape and lifestyle of an adult moth. Yet these caterpillars can sense, and appear to like, the adult sex pheromone of their species, an international team reports September 4 in Nature Communications.
“This is a funny fact because sex pheromones are supposed to be for sex,” says coauthor Emmanuelle Jacquin-Joly of the French agricultural research agency INRA in Versailles. Adult female moths release puffs of these chemicals, and males catching a whiff — sometimes from considerable distances — sniff their way through the night to the female.