Gut bacteria compounds bring cockroaches together

Talk about micromanagement: Gut microbes may control a cockroach’s social life.

Gut bacteria in young German cockroaches (Blattella germanica) produce fragrant compounds that, when excreted, attract other roaches, researchers report December 7 in Proceedings of the National Academy of Sciences. The microbes’ chemical creations may play a large role in encouraging roaches to cluster — and may even provide each cockroach colony with its own distinct aroma, the scientists say.

Of 40 compounds the team identified in normal roach dung that might produce an enticing scent, 31 were reduced by at least half in the dung of roaches that lacked gut bacteria. And a cockroach’s feces became much less enticing to other roaches if the insect was raised in a bacteria-free environment, the scientists found. Beyond drawing roaches together, these compounds could provide B. germanica with information about the health or size of a colony, the researchers suggest.