The same chemicals that attract can also maintain the species barrier
Honey’s sweet smell attracts more flies than does vinegar’s sour odor, but the ultimate fruit-fly magnet is eau de nothing.
Ditching pheromones makes male and female fruit flies super-sexy to male flies, even to males of other species, Joel Levine, a neurogeneticist at the University of Toronto at Mississauga, and his colleagues report in the October 15 Nature. The discovery suggests pheromones can be back-off rather than come-hither signals. The finding could lead to a better understanding of the chemical signals that help flies and other animals interpret the world, i