Bacteria Are People Too
“I’ll bet a bacterium could hold its own in any Parisian café. They don’t need to study existentialism at the Sorbonne; they live it every day.”
David Cowles
1000 words, 5 minute read
“If I only had a brain,” intones Scarecrow in the Wizard of Oz. Of course, it turns out that Scarecrow didn’t need a brain! Neither do bacteria!
Prokaryotic (non-nucleated) unicellular organisms, like bacteria, first appeared on Earth about 4 billion years ago. Today, they cover the planet and fill nearly every ecological niche. All life on Earth is, or evolved from, a prokaryote. They survive naturally, or they can quickly evolve to survive, in almost any environment, no matter how hostile. Like us, they can even alter their environment to make it more habitable.
Originally anaerobic on an oxygen poor planet, bacteria merged to form the first eukaryotic (nucleated) cells which in turn formed plants that produce the oxygen that bacteria later learned to breathe. Wrap your noodle around that one! But before there was sufficient atmospheric oxygen, bacteria used iron to power its cellular processes. “If I don’t have blue, I use red.” (Picasso)
Bacteria are as close as nature has come to creating a ‘quantum of life’, i.e. the minimal configuration of molecules required to support phenomena we recognize as ‘living’. No surprise then that we view bacteria as irremediably stupid. “Dumb as dirt!” Of course…they are dirt!
But how is it then that bacteria compete with us, and certain insects, for dominion over Earth? Like Scarecrow, they have no organelle that performs the functions we associate with a ‘brain’; but like Scarecrow, they apparently don’t need one. They have devised other ways to ‘think’.
Everything wants to think. Sum ergo Cogito (I am therefore I think). But thinking does not require neurons; it can happen using a multitude of physical pathways. If things want to think, they’ll find a way to do so. Bacteria don’t need brains to think, just as they don’t need sex to reproduce. They freely swap genes with one another, no ‘dinner and a movie’ required.
People say that Anarchism is an impractical political ideology. “For all its theoretical appeal, it simply won’t work.” Really? Bacterial society is paradigmatically anarchic, and it’s worked for 4 billion years. There’s no whiff of authority. Cooperation is spontaneous. Unlike some humans, they understand that they are ‘better together’. As for conflict, like unsupervised kids on a 1950’s playground, bacteria work stuff out…by themselves.
In our finer moments, we humans recreate anarchic utopias too. A recent post on this site explored the Vinca civilization of central Europe, c. 5000 BCE. Sophisticated urban planning and a division of labor were apparently accomplished without a central government, a bureaucracy, a police force or a standing army.
Later, between 1250 to 1050 BCE, we see another attempt at anarchic utopia, this time in Palestine. According to the Old Testament Book of Judges, “In those days Israel had no king; everyone did what was right in their own eyes.” (21: 25)
When circumstances required a coordinated response, charismatic leaders called ‘judges’ emerged ad hoc, and with the consent of the elders and the people, they provided the temporary leadership needed to address the immediate challenge…and then they returned home to tend their flocks.
So, how do bacteria think? We still have a lot to learn, but scientists have just discovered that bacteria can create memories by regulating the amount of iron in their systems. Researchers at The University of Texas at Austin found that bacteria use iron levels to store information about different behaviors that can then be activated in response to certain stimuli. “Bacteria don’t have brains, but they can gather information from their environment, and…they can store that information and quickly access it later for their benefit,” said Souvik Bhattacharyya.
Most intriguingly, bacteria pass that information along to their progeny, down at least to the 4th generation. Humans pass along information two ways: long term via genes, short term via culture. Bacteria have it the other way around. They modify their genes on an almost daily basis but their ‘culture’ preserves memories for at least 4 generations.
Single, free-floating bacteria have naturally varying levels of iron. Bacterial cells with lower levels of iron tend to swarm while the bacteria that form biofilms have higher iron levels. You may be forgiven for thinking that cells with low iron gravitate to ‘swarming’ while their high iron cousin prefer ‘filming’; after all, you think that smarter people become doctors while less smart people work at McDonald’s. But you’re wrong…on both counts!
Any bacterium can swarm or film; it just needs to ‘decide’ what it wants to do; then it adjusts its iron content accordingly. When iron levels are low, bacteria form fast-moving swarms to search for new sources of iron. When iron levels are higher, bacteria are more likely to feel satisficed and so stay put and form films.
“I know who I am and I know that I can be whoever I want to be.” (J-P. Sartre) I’ll bet a bacterium could hold its own in any Parisienne café. They don’t need to study Existentialism at the Sorbonne; they live it every day. So hats off to our unicelluar cousins… and don’t forget, bacteria are people too.