The Bacterial Stack That Makes Us

Those who are skeptical of the theory of human evolution tend to sneer at the idea that humans evolved from apes.  However, the evolutionary news is actually much more humbling if one takes the long view; we evolved up from mere bacteria, and in fact, we are still a massive stack of cooperating tiny organisms that collectively generate behaviors that are motivated by pure self-interest. Seen through this lens, what makes the existential “us” is much more complicated.

My burgeoning awareness and subsequent wondering about what we actual are came about as a result of listening to the Dave Asprey podcast. Asprey is a self-described “bio-hacker” and one of his ongoing themes is the vital importance of the mitochondria that we carry in each of our cells. The mitochondria are the powerhouses of our cells, and Asprey describes them as “ancient bacteria” that our cells incorporated a long time ago. The mitochondria are the conversion factories that take our various inputs (food and oxygen) and generate chemical outputs of energy. Without our billions of mitochondria, we’re all dead and each mitochondrion is the descendent of a once free-standing organism. They are the bedrock of what we are.

Another Asprey obsession is with the masses of bacteria in the human intestines, often referred to as “the gut microbiome.” Within each human, there are trillions of bacteria in the gut that are a vital part of the digestion process. There are a multitude of kinds, so many, in fact,  that if you were to add up all the unique DNA strands of the gut bacteria and line up the DNA strands of the individual human, the bacterial DNA combinations would be greater. “We” do not even add up to the majority of our own DNA.

So, if each of our cells is powered by a collective of even smaller organisms that were once independent creatures, and they, in turn, can only function with the cooperation of another set of tiny creatures so numerous that they actually have a greater DNA volume than we do, my question is… What are we?

Further, there are those that believe that the gut microbiome is having a profound and possibly majority effect on our thinking. These creatures want to live, and one would suppose, have a sort of individual will that adds up to a collective intention. If the gut environment is suboptimal because of the food the inhabitants are being fed, that fact may register in the human brain as some symptom, like depression. Cravings and other longings for certain foods, or a strong dislike of certain foods, may originate in the gut.

Perhaps some forms of mental illness reside there, but who knows? This is all a fairly new area of inquiry, one that makes the previous debates about evolution involving man and ape rather simplistic. The apes are in the same existential boats with us on this one; they, too, are massive stacks of cooperating bacteria, all under the influence of the legislature of the gut.

None of these fascinating subjects presupposes the existence or lack of existence of a God of creation, at least not in my mind. The entire series of weird arrangements that make up the universe seems more like a set of competing experiments in how to organize life, all as bizarre and unlikely as the next. Perhaps we are a stack of cooperating bacteria, jellyfish manage to live without the benefit of a brain, the deepest, darkest trenches of the Earth’s oceans are teeming with adapted versions of life, Saturn has rings and Jupiter does not, and a meteor strike could reset the biological clock in any given epoch. What a glorious mess!

My assumption is that life is everywhere in the universe, gathering in complexity and then breaking down to rebuild again. It’s a process with a purpose we shall not know with our limited perceptive capacity and in our very limited time. Humans are the penultimate creature of this planet, but we are still in the primitive stage of understanding who, where, and what we are. With our ancient bacterial origins and our bodies full of separate but fellow travelers,  we look through a glass darkly, and will for a long time to come.