A concept known as ‘percolation’ is helping microbiologists explain how communities of bacteria can effectively relay signals across long distances. Once regarded as a simple cluster of microorganisms, communities of bacteria have been found to employ a strategy we use to brew coffee and extract oil from the sea. Percolation helps the microscopic community thrive and survive threats, such as chemical attacks from antibiotics.
Biofilm communities inhabit locations all around us, from soil to drain pipes to the surface of our teeth. Cells at the edge of these communities tend to grow more robustly than their interior counterparts because they have access to more nutrients. To keep this edge growth in check and ensure the entire community is fit and balanced, the “hungry” members of the biofilm interior send electrochemical signals to members at the exterior. These signals halt consumption at the edge, allowing nutrients to pass through to the interior cells to avoid starvation.
“This keeps the interior fed well enough and if a chemical attack comes and takes out some of the exterior cells, then the protected interior is able to continue and the whole population can survive,” said Larkin, a UC San Diego Biological Sciences postdoctoral scholar. “It is essential that the electrochemical signal be consistently transmitted all the way to the biofilm edge because that is the place where the growth must be stopped for the community to reap the most benefit from signalling.”
“It’s interesting that these bacteria, which are so-called simple, single-cell organisms, are using a fairly sophisticated strategy to solve this community-level problem,” said Larkin. “It’s sophisticated enough that we humans are using it to extract oil, for example.” (open access) – Joseph W. Larkin, M. Süel et al., Signal Percolation within a Bacterial Community, Cell July 25, 2018 DOI: https://doi.org/10.1016/j.cels.2018.06.005 More.
Yes, it is “interesting” that bacteria use such a sophisticated strategy to keep feeding a colony. That raises a question: If microbial mats have been around for three and a half billion years, did they not encounter some of the same basic physical problems as described in this research?
If the mats did not have this “fairly sophisticated strategy” then, what strategy were they using? If they did have it, how did they just somehow happen to evolve a sophisticated strategy by natural selection acting on random mutations (Darwinism) within a specific, limited time frame?
More research, less Darwinism.
See also: Microbial mats show fossil structures from 3.5 billion years ago