A new study has suggested that bacteria that live on the fruitfly Drosophila melanogaster can affect their host's choice of mate by altering the fly's pheromones.
This in turn could lead to the evolution of new fly species — suggesting that bacteria can indirectly change the species of their hosts, reports Nature.
Eugene Rosenberg, a microbiologist at Tel-Aviv University, suspected that a change in diet acts on symbiotic bacteria living on the flies, rather than directly on the flies themselves.
The find is consistent with 'hologenome' theory – which suggests that natural selection, which drives evolution, acts on a host and its symbiotic partners as a single unit rather than on each species in isolation.
The fruitflies developed a mating preference just a single generation after they were introduced to a new diet.
"There''s a hint from analytical data that they are altering the sexual pheromones, but this really has to be looked at more closely," said Rosenberg.
Rosenberg says the next step is to investigate whether this mechanism is occurring in natural fruitfly populations, and to pin down how the bacteria are passed from one generation to the next.
The findings are published this week in Proceedings of the National Academy of Sciences.