Communications is a fundamental characteristics of life. It is found everywhere and in its primeval form it is based on molecules exchange. This is true for insects that use pheromones to communicate one another, but it is also true within our body where most communications take place through the exchange of molecules. It is true also at bacteria level where scientists have observed that the formation of biofilms, like the one in the photo, depends on these molecules based communications.
So far it has been difficult to trace, listen to, this communications since intercepting molecules is tricky. But now researchers at the Columbia University have developed a chip upon which a biofilm of bacteria can be observed as communications takes place.
Notice that this is a communication among autonomous systems, each bacteria is on its own. By emitting a molecule it changes its environment and this change its perceived by neighbour bacteria that in turns, autonomously, will emit other molecules thus changing the environment once more and affecting the first bacteria. Don't thinks that our communications is completely different: we are using words/sentences and these change our surrounding environment, causing other people within hearing distance to reach with other sentences that in turn will affect us... we are indeed autonomous systems! However it is easy (today) to register words and analyse the effects in terms of interactions.
What researchers at Columbia did was to create a chip that can sense electrical variation with an amazing resolution. Each molecule has its own electrical signature and this allows the chip to detect the molecule and its position. By computing all molecules spatially and temporally researchers have been able to trace the communications in the bacteria colony.
They have also observed that by altering this communication it is possible to disrupt the growth of the biofilm, something that may turn out to be life saving in a hospital environment to block bacteria infestation, as an example on medical devices.