It doesn’t take brains to have some smarts. New research shows that even bacteria can evolve to predict upcoming events based on clues, like a dog salivating at the sound of the dinner bell.
“It’s really the first evidence that single-celled organisms — bacteria — also have this ability for associative learning,” says Saeed Tavazoie, a molecular biologist at Princeton University who led the research on E. coli bacteria. The discovery reveals a kind of predictive intelligence in how microbes interpret sensory cues from their environments. Understanding how this predictive ability affects bacteria’s behavior could help scientists control microbes better, benefitting industry and the treatment of infectious diseases. When E. coli enters a person’s body, its environment immediately becomes warmer. Later, as the microbe moves into the person’s gut, oxygen becomes scarce. Tavazoie and his colleagues found that warm temperatures alone triggered the microbes to switch to a less efficient, low-oxygen mode. The bacteria anticipated the coming lack of oxygen and were preparing for it, the researchers reported online May 8 in Science.