To warn others, researchers suggest. We were going to save this one for Halloween but that’s too far away:
These death shrieks aren’t audible; rather, they are chemical alarms that the bacteria broadcast while on the verge of death, an action known as necrosignaling.
Through necrosignaling, bacteria alert their swarming neighbors to the presence of a deadly threat, and thereby save the majority of the swarm (a bacterial colony that’s on the move). When confronted by a threat such as antibiotics, the bacteria’s chemical death cries can provide survivors enough time to acquire mutations that convey antibiotic resistance, scientists reported in a new study.Mindy Weisberger, “‘Death screams’ of swarming bacteria help their comrades survive antibiotic attacks” at LiveScience
Paper. (open access)
A study author suggests that “Swarms of bacteria may collectively cultivate different subpopulations as an evolutionary survival strategy — if new antibiotics kill the vulnerable members of the swarm, their deaths will help to protect the rest.” (LiveScience)
That implies that bacteria have a sort of collective mind, doesn’t it?
In any event, a sort of intelligence seems instantiated in bacteria. The study authors are right to raise the question of whether treating them as simple blobs that can be killed by the right chemicals really works.
See also: In What Ways Are Bacteria Intelligent? As antibiotic resistance grows, researchers are discovering that these microbes are not just single, simple cells. We must understand the surprisingly complex ways bacteria “think” in order to keep them in check.